Update software recording engine to latest codec interface.

Basically, just give it a good rewrite.

Software codec recording can be implemented in a more straightforward
and simple manner and made more robust through the better codec
control now available.

Encoded audio buffer uses a packed format instead of fixed-size
chunks and uses smaller data headers leading to more efficient usage.
The greatest benefit is with a VBR format like wavpack which needs
to request a maximum size but only actually ends up committing part
of that request.

No guard buffers are used for either PCM or encoded audio. PCM is
read into the codec's provided buffer and mono conversion done at
that time in the core if required. Any highly-specialized sample
conversion is still done within the codec itself, such as 32-bit
(wavpack) or interleaved mono (mp3).

There is no longer a separate filename array. All metadata goes
onto the main encoded audio buffer, eliminating any predermined
file limit on the buffer as well as not wasting the space for
unused path queue slots.

The core and codec interface is less awkward and a bit more sensible.
Some less useful interface features were removed. Threads are kept
on narrow code paths ie. the audio thread never calls encoding
functions and the codec thread never calls file functions as before.

Codecs no longer call file functions directly. Writes are buffered
in the core and data written to storage in larger chunks to speed up
flushing of data. In fact, codecs are no longer aware of the stream
being a file at all and have no access to the fd.

SPDIF frequency detection no longer requires a restart of recording
or plugging the source before entering the screen. It will poll
for changes and update when stopped or prerecording (which does
discard now-invalid prerecorded data).

I've seen to it that writing a proper header on full disk works
when the format makes it reasonably practical to do so. Other cases
may have incorrect data sizes but sample info will be in tact. File
left that way may play anyway.

mp3_enc.codec acquires the ability to write 'Info' headers with LAME
tags to make it gapless (bonus).

Change-Id: I670685166d5eb32ef58ef317f50b8af766ceb653
Reviewed-on: http://gerrit.rockbox.org/493
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>

5 files changed, 862 insertions, 1224 deletions

diff --git a/lib/rbcodec/codecs/aiff_enc.c b/lib/rbcodec/codecs/aiff_enc.c
index 8e9246d2bb..fb8db384a3 100644
--- a/lib/rbcodec/codecs/aiff_enc.c
+++ b/lib/rbcodec/codecs/aiff_enc.c
@@ -8,6 +8,7 @@
  * $Id$
  *
  * Copyright (C) 2006 Antonius Hellmann
+ * Copyright (C) 2006-2013 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -47,10 +48,15 @@ struct aiff_header
 #define PCM_DEPTH_BYTES             2
 #define PCM_DEPTH_BITS             16
 #define PCM_SAMP_PER_CHUNK       2048
-#define PCM_CHUNK_SIZE          (PCM_SAMP_PER_CHUNK*4)
+
+static int num_channels;
+static uint32_t sample_rate;
+static size_t frame_size;
+static size_t pcm_size;
+static uint32_t num_sample_frames;
 
 /* Template headers */
-struct aiff_header aiff_header =
+static const struct aiff_header aiff_template_header =
 {
     { 'F', 'O', 'R', 'M' },             /* form_id               */
     0,                                  /* form_size         (*) */
@@ -65,336 +71,193 @@ struct aiff_header aiff_header =
     0,                                  /* ssnd_size         (*) */
     htobe32(0),                         /* offset                */
     htobe32(0),                         /* block_size            */
+    /* (*) updated when finalizing stream */
 };
 
-/* (*) updated when finalizing file */
-
-static int      num_channels IBSS_ATTR;
-static int      rec_mono_mode IBSS_ATTR;
-static uint32_t sample_rate;
-static uint32_t enc_size;
-static int32_t  err          IBSS_ATTR;
+static inline void frame_htobe(uint32_t *p, size_t size)
+{
+#ifdef ROCKBOX_LITTLE_ENDIAN
+    /* Byte-swap samples, stereo or mono */
+    do
+    {
+        uint32_t t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+    }
+    while (size -= 8 * 2 * PCM_DEPTH_BYTES);
+#endif /* ROCKBOX_LITTLE_ENDIAN */
+    (void)p; (void)size;
+}
 
 /* convert unsigned 32 bit value to 80-bit floating point number */
 static void uint32_h_to_ieee754_extended_be(uint8_t f[10], uint32_t l)
-                                                ICODE_ATTR;
-static void uint32_h_to_ieee754_extended_be(uint8_t f[10], uint32_t l)
 {
-    int32_t exp;
-
     ci->memset(f, 0, 10);
 
     if (l == 0)
         return;
 
-    for (exp = 30; (l & (1ul << 31)) == 0; exp--)
-        l <<= 1;
+    int shift = __builtin_clz(l);
 
     /* sign always zero - bit 79 */
-    /* exponent is 0-31 (normalized: 31 - shift + 16383) - bits 64-78 */
+    /* exponent is 0-31 (normalized: 30 - shift + 16383) - bits 64-78 */
     f[0] = 0x40;
-    f[1] = (uint8_t)exp;
+    f[1] = (uint8_t)(30 - shift);
     /* mantissa is value left justified with most significant non-zero
        bit stored in bit 63 - bits 0-63 */
+    l <<= shift;
     f[2] = (uint8_t)(l >> 24);
     f[3] = (uint8_t)(l >> 16);
     f[4] = (uint8_t)(l >>  8);
     f[5] = (uint8_t)(l >>  0);
-} /* uint32_h_to_ieee754_extended_be */
-
-/* called version often - inline */
-static inline bool is_file_data_ok(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool is_file_data_ok(struct enc_file_event_data *data)
-{
-    return data->rec_file >= 0 && (long)data->chunk->flags >= 0;
-} /* is_file_data_ok */
+}
 
-/* called version often - inline */
-static inline bool on_write_chunk(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool on_write_chunk(struct enc_file_event_data *data)
+static int on_stream_data(struct enc_chunk_data *data)
 {
-    if (!is_file_data_ok(data))
-        return false;
+    size_t size = data->hdr.size;
 
-    if (data->chunk->enc_data == NULL)
-    {
-#ifdef ROCKBOX_HAS_LOGF
-        ci->logf("aiff enc: NULL data");
-#endif
-        return true;
-    }
+    if (ci->enc_stream_write(data->data, size) != (ssize_t)size)
+        return -1;
 
-    if (ci->write(data->rec_file, data->chunk->enc_data,
-                  data->chunk->enc_size) != (ssize_t)data->chunk->enc_size)
-        return false;
+    pcm_size += size;
+    num_sample_frames += data->pcm_count;
 
-    data->num_pcm_samples += data->chunk->num_pcm;
-    return true;
-} /* on_write_chunk */
+    return 0;
+}
 
-static bool on_start_file(struct enc_file_event_data *data)
+static int on_stream_start(void)
 {
-    if ((data->chunk->flags & CHUNKF_ERROR) || *data->filename == '\0')
-        return false;
-
-    data->rec_file = ci->open(data->filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
-
-    if (data->rec_file < 0)
-        return false;
-
     /* reset sample count */
-    data->num_pcm_samples = 0;
+    pcm_size = 0;
+    num_sample_frames = 0;
 
-    /* write template headers */
-    if (ci->write(data->rec_file, &aiff_header, sizeof (aiff_header))
-            != sizeof (aiff_header))
-    {
-        return false;
-    }
+    /* write template header */
+    if (ci->enc_stream_write(&aiff_template_header,
+                             sizeof (struct aiff_header))
+            != sizeof (struct aiff_header))
+        return -1;
 
-    data->new_enc_size += sizeof(aiff_header);
-    return true;
-} /* on_start_file */
+    return 0;
+}
 
-static bool on_end_file(struct enc_file_event_data *data)
+static int on_stream_end(union enc_chunk_hdr *hdr)
 {
-    /* update template headers */
-    struct aiff_header hdr;
-    uint32_t data_size;
+    /* update template header */
+    struct aiff_header aiff;
 
-    if (!is_file_data_ok(data))
-        return false;
-
-    if (ci->lseek(data->rec_file, 0, SEEK_SET) != 0 ||
-        ci->read(data->rec_file, &hdr, sizeof (hdr)) != sizeof (hdr))
+    if (hdr->err)
     {
-        return false;
+        /* Called for stream error; get correct data size */
+        ssize_t size = ci->enc_stream_lseek(0, SEEK_END);
+
+        if (size > (ssize_t)sizeof (aiff))
+        {
+            pcm_size = size - sizeof (aiff);
+            num_sample_frames = pcm_size / (PCM_DEPTH_BYTES*num_channels);
+        }
     }
 
-    data_size = data->num_pcm_samples*num_channels*PCM_DEPTH_BYTES;
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0)
+        return -1;
+
+    if (ci->enc_stream_read(&aiff, sizeof (aiff)) != sizeof (aiff))
+        return -2;
 
     /* 'FORM' chunk */
-    hdr.form_size         = htobe32(data_size + sizeof (hdr) - 8);
+    aiff.form_size = htobe32(pcm_size + sizeof (aiff) - 8);
 
     /* 'COMM' chunk */
-    hdr.num_channels      = htobe16(num_channels);
-    hdr.num_sample_frames = htobe32(data->num_pcm_samples);
-    uint32_h_to_ieee754_extended_be(hdr.sample_rate, sample_rate);
+    aiff.num_channels = htobe16(num_channels);
+    aiff.num_sample_frames = htobe32(num_sample_frames);
+    uint32_h_to_ieee754_extended_be(aiff.sample_rate, sample_rate);
 
     /* 'SSND' chunk */
-    hdr.ssnd_size         = htobe32(data_size + 8);
+    aiff.ssnd_size = htobe32(pcm_size + 8);
 
-    if (ci->lseek(data->rec_file, 0, SEEK_SET) != 0 ||
-        ci->write(data->rec_file, &hdr, sizeof (hdr)) != sizeof (hdr) ||
-        ci->close(data->rec_file) != 0)
-    {
-        return false;
-    }
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0)
+        return -3;
 
-    data->rec_file = -1;
+    if (ci->enc_stream_write(&aiff, sizeof (aiff)) != sizeof (aiff))
+        return -4;
 
-    return true;
-} /* on_end_file */
+    return 0;
+}
 
-static void enc_events_callback(enum enc_events event, void *data)
-                                    ICODE_ATTR;
-static void enc_events_callback(enum enc_events event, void *data)
+/* this is the codec entry point */
+enum codec_status codec_main(enum codec_entry_call_reason reason)
 {
-    switch (event)
-    {
-    case ENC_WRITE_CHUNK:
-        if (on_write_chunk((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_START_FILE:
-        if (on_start_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_END_FILE:
-        if (on_end_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    default:
-        return;
-    }
-
-    /* Something failed above. Signal error back to core. */
-    ((struct enc_file_event_data *)data)->chunk->flags |= CHUNKF_ERROR;
-} /* enc_events_callback */
+    return CODEC_OK;
+    (void)reason;
+}
 
-/* convert native pcm samples to aiff format samples */
-static inline void sample_to_mono(uint32_t **src, uint32_t **dst)
+/* this is called for each file to process */
+enum codec_status ICODE_ATTR codec_run(void)
 {
-    int32_t lr1, lr2;
+    enum { GETBUF_ENC, GETBUF_PCM } getbuf = GETBUF_ENC;
+    struct enc_chunk_data *data = NULL;
 
-    switch(rec_mono_mode)
+    /* main encoding loop */
+    while (1)
     {
-        case 1:
-            /* mono = L */
-            lr1 = *(*src)++;
-            lr1 = lr1 >> 16;
-            lr2 = *(*src)++;
-            lr2 = lr2 >> 16;
-            break;
-        case 2:
-            /* mono = R */
-            lr1 = *(*src)++;
-            lr1 = (int16_t)lr1;
-            lr2 = *(*src)++;
-            lr2 = (int16_t)lr2;
-            break;
-        case 0:
-        default:
-            /* mono = (L+R)/2 */
-            lr1 = *(*src)++;
-            lr1 = (int16_t)lr1 + (lr1 >> 16) + err;
-            err = lr1 & 1;
-            lr1 >>= 1;
-
-            lr2 = *(*src)++;
-            lr2 = (int16_t)lr2 + (lr2 >> 16) + err;
-            err = lr2 & 1;
-            lr2 >>= 1;
+        enum codec_command_action action = ci->get_command(NULL);
+
+        if (action != CODEC_ACTION_NULL)
             break;
-    }
-    *(*dst)++ = htobe32((lr1 << 16) | (uint16_t)lr2);
-} /* sample_to_mono */
 
-static void chunk_to_aiff_format(uint32_t *src, uint32_t *dst) ICODE_ATTR;
-static void chunk_to_aiff_format(uint32_t *src, uint32_t *dst)
-{
-    if (num_channels == 1)
-    {
-        /* On big endian:
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr|
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr| =>
-         *  |MMMMMMMMmmmmmmmm|MMMMMMMMmmmmmmmm|
-         *
-         * On little endian:
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR|
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR| =>
-         *  |MMMMMMMMmmmmmmmm|MMMMMMMMmmmmmmmm|
-         */
-        uint32_t *src_end = src + PCM_SAMP_PER_CHUNK;
-
-        do
-        {
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-        }
-        while (src < src_end);
-    }
-    else
-    {
-#ifdef ROCKBOX_BIG_ENDIAN
-        /*  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr| =>
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr|
-         */
-        ci->memcpy(dst, src, PCM_CHUNK_SIZE);
-#else
-        /*  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR| =>
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr|
-         */
-        uint32_t *src_end = src + PCM_SAMP_PER_CHUNK;
-
-        do
+        /* First obtain output buffer; when available, get PCM data */
+        switch (getbuf)
         {
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
+        case GETBUF_ENC:
+            if (!(data = ci->enc_encbuf_get_buffer(frame_size)))
+                continue;
+            getbuf = GETBUF_PCM;
+        case GETBUF_PCM:
+            if (!ci->enc_pcmbuf_read(data->data, PCM_SAMP_PER_CHUNK))
+                continue;
+            getbuf = GETBUF_ENC;
         }
-        while (src < src_end);
-#endif
-    }
-} /* chunk_to_aiff_format */
 
-static bool init_encoder(void)
-{
-    struct enc_inputs     inputs;
-    struct enc_parameters params;
-
-    if (ci->enc_get_inputs         == NULL ||
-        ci->enc_set_parameters     == NULL ||
-        ci->enc_get_chunk          == NULL ||
-        ci->enc_finish_chunk       == NULL ||
-        ci->enc_get_pcm_data       == NULL )
-        return false;
-
-    ci->enc_get_inputs(&inputs);
-
-    if (inputs.config->afmt != AFMT_AIFF)
-        return false;
-
-    sample_rate  = inputs.sample_rate;
-    num_channels = inputs.num_channels;
-    rec_mono_mode = inputs.rec_mono_mode;
-    err          = 0;
-
-    /* configure the buffer system */
-    params.afmt            = AFMT_AIFF;
-    enc_size               = PCM_CHUNK_SIZE*inputs.num_channels / 2;
-    params.chunk_size      = enc_size;
-    params.enc_sample_rate = sample_rate;
-    params.reserve_bytes   = 0;
-    params.events_callback = enc_events_callback;
-    ci->enc_set_parameters(&params);
-
-    return true;
-} /* init_encoder */
+        data->hdr.size = frame_size;
+        data->pcm_count = PCM_SAMP_PER_CHUNK;
 
-/* this is the codec entry point */
-enum codec_status codec_main(enum codec_entry_call_reason reason)
-{
-    if (reason == CODEC_LOAD) {
-        if (!init_encoder())
-            return CODEC_ERROR;
-    }
-    else if (reason == CODEC_UNLOAD) {
-        /* reset parameters to initial state */
-        ci->enc_set_parameters(NULL);
+        frame_htobe((uint32_t *)data->data, frame_size);
+
+        ci->enc_pcmbuf_advance(PCM_SAMP_PER_CHUNK);
+        ci->enc_encbuf_finish_buffer();
     }
 
     return CODEC_OK;
 }
 
-/* this is called for each file to process */
-enum codec_status codec_run(void)
+/* this is called by recording system */
+int ICODE_ATTR enc_callback(enum enc_callback_reason reason,
+                            void *params)
 {
-    /* main encoding loop */
-    while (ci->get_command(NULL) != CODEC_ACTION_HALT)
+    if (LIKELY(reason == ENC_CB_STREAM))
     {
-        uint32_t *src = (uint32_t *)ci->enc_get_pcm_data(PCM_CHUNK_SIZE);
-        struct enc_chunk_hdr *chunk;
-
-        if (src == NULL)
-            continue;
-
-        chunk           = ci->enc_get_chunk();
-        chunk->enc_size = enc_size;
-        chunk->num_pcm  = PCM_SAMP_PER_CHUNK;
-        chunk->enc_data = ENC_CHUNK_SKIP_HDR(chunk->enc_data, chunk);
-
-        chunk_to_aiff_format(src, (uint32_t *)chunk->enc_data);
-
-        ci->enc_finish_chunk();
+        switch (((union enc_chunk_hdr *)params)->type)
+        {
+        case CHUNK_T_DATA:
+            return on_stream_data(params);
+        case CHUNK_T_STREAM_START:
+            return on_stream_start();
+        case CHUNK_T_STREAM_END:
+            return on_stream_end(params);
+        }
+    }
+    else if (reason == ENC_CB_INPUTS)
+    {
+        struct enc_inputs *inputs = params;
+        sample_rate = inputs->sample_rate;
+        num_channels = inputs->num_channels;
+        frame_size = PCM_SAMP_PER_CHUNK*PCM_DEPTH_BYTES*num_channels;
     }
 
-    return CODEC_OK;
+    return 0;
 }
diff --git a/lib/rbcodec/codecs/codecs.h b/lib/rbcodec/codecs/codecs.h
index ae4233b7a6..672b1ded53 100644
--- a/lib/rbcodec/codecs/codecs.h
+++ b/lib/rbcodec/codecs/codecs.h
@@ -36,7 +36,7 @@
 #endif
 #if (CONFIG_CODEC == SWCODEC)
 #ifdef HAVE_RECORDING
-#include "pcm_record.h"
+#include "enc_base.h"
 #endif
 #include "dsp_core.h"
 #include "dsp_misc.h"
@@ -72,12 +72,12 @@
 #define CODEC_ENC_MAGIC 0x52454E43 /* RENC */
 
 /* increase this every time the api struct changes */
-#define CODEC_API_VERSION 45
+#define CODEC_API_VERSION 46
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
    new function which are "waiting" at the end of the function table) */
-#define CODEC_MIN_API_VERSION 45
+#define CODEC_MIN_API_VERSION 46
 
 /* reasons for calling codec main entrypoint */
 enum codec_entry_call_reason {
@@ -96,6 +96,9 @@ enum codec_command_action {
     CODEC_ACTION_HALT = -1,
     CODEC_ACTION_NULL = 0,
     CODEC_ACTION_SEEK_TIME = 1,
+#ifdef HAVE_RECORDING
+    CODEC_ACTION_STREAM_FINISH = 2,
+#endif
 };
 
 /* NOTE: To support backwards compatibility, only add new functions at
@@ -200,24 +203,18 @@ struct codec_api {
 #endif
 
 #ifdef HAVE_RECORDING
-    void            (*enc_get_inputs)(struct enc_inputs *inputs);
-    void            (*enc_set_parameters)(struct enc_parameters *params);
-    struct enc_chunk_hdr * (*enc_get_chunk)(void);
-    void            (*enc_finish_chunk)(void);
-    unsigned char * (*enc_get_pcm_data)(size_t size);
-    size_t          (*enc_unget_pcm_data)(size_t size);
-
-    /* file */
-    int (*open)(const char* pathname, int flags, ...);
-    int (*close)(int fd);
-    ssize_t (*read)(int fd, void* buf, size_t count);
-    off_t (*lseek)(int fd, off_t offset, int whence);
-    ssize_t (*write)(int fd, const void* buf, size_t count);
+    int (*enc_pcmbuf_read)(void *buf, int count);
+    int (*enc_pcmbuf_advance)(int count);
+    struct enc_chunk_data * (*enc_encbuf_get_buffer)(size_t need);
+    void (*enc_encbuf_finish_buffer)(void);
+    ssize_t (*enc_stream_read)(void *buf, size_t count);
+    off_t (*enc_stream_lseek)(off_t offset, int whence);
+    ssize_t (*enc_stream_write)(const void *buf, size_t count);
     int (*round_value_to_list32)(unsigned long value,
                                  const unsigned long list[],
                                  int count,
                                  bool signd);
-#endif
+#endif /* HAVE_RECORDING */
 
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
@@ -229,6 +226,7 @@ struct codec_header {
     enum codec_status(*entry_point)(enum codec_entry_call_reason reason);
     enum codec_status(*run_proc)(void);
     struct codec_api **api;
+    void * rec_extension[]; /* extension for encoders */
 };
 
 #ifdef CODEC
@@ -249,7 +247,7 @@ extern unsigned char plugin_end_addr[];
         __attribute__ ((section (".header")))= { \
         { CODEC_ENC_MAGIC, TARGET_ID, CODEC_API_VERSION, \
         plugin_start_addr, plugin_end_addr }, codec_start, \
-        codec_run, &ci };
+        codec_run, &ci, { enc_callback } };
 
 #else /* def SIMULATOR */
 /* decoders */
@@ -262,7 +260,7 @@ extern unsigned char plugin_end_addr[];
 #define CODEC_ENC_HEADER \
         const struct codec_header __header = { \
         { CODEC_ENC_MAGIC, TARGET_ID, CODEC_API_VERSION, NULL, NULL }, \
-        codec_start, codec_run, &ci };
+        codec_start, codec_run, &ci, { enc_callback } };
 #endif /* SIMULATOR */
 #endif /* CODEC */
 
@@ -277,12 +275,19 @@ void *codec_get_buffer_callback(size_t *size);
 int codec_load_buf(int hid, struct codec_api *api);
 int codec_load_file(const char* codec, struct codec_api *api);
 int codec_run_proc(void);
-int codec_halt(void);
 int codec_close(void);
+#if CONFIG_CODEC == SWCODEC && defined(HAVE_RECORDING)
+enc_callback_t codec_get_enc_callback(void);
+#else
+#define codec_get_enc_callback()  NULL
+#endif
 
 /* defined by the codec */
 enum codec_status codec_start(enum codec_entry_call_reason reason);
 enum codec_status codec_main(enum codec_entry_call_reason reason);
 enum codec_status codec_run(void);
+#if CONFIG_CODEC == SWCODEC && defined(HAVE_RECORDING)
+int enc_callback(enum enc_callback_reason reason, void *params);
+#endif
 
 #endif /* _CODECS_H_ */
diff --git a/lib/rbcodec/codecs/mp3_enc.c b/lib/rbcodec/codecs/mp3_enc.c
index 000eedd849..a349f99f25 100644
--- a/lib/rbcodec/codecs/mp3_enc.c
+++ b/lib/rbcodec/codecs/mp3_enc.c
@@ -8,6 +8,7 @@
  * $Id$
  *
  * Copyright (C) 2006 Antonius Hellmann
+ * Copyright (C) 2006-2013 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -37,17 +38,9 @@
 
 CODEC_ENC_HEADER
 
-#define ENC_PADDING_FRAMES1        2
-#define ENC_PADDING_FRAMES2        4
-#define ENC_DELAY_SAMP           576
-#define ENC_DELAY_SIZE          (ENC_DELAY_SAMP*4)
-#define SAMP_PER_FRAME1         1152
-#define SAMP_PER_FRAME2          576
-#define PCM_CHUNK_SIZE1         (SAMP_PER_FRAME1*4)
-#define PCM_CHUNK_SIZE2         (SAMP_PER_FRAME2*4)
-#define SAMPL2                576
-#define SBLIMIT                32
-#define HTN                    16
+#define SAMPL2      576
+#define SBLIMIT      32
+#define HTN          16
 #define memcpy      ci->memcpy
 #define memset      ci->memset
 #define putlong(c, s)  if(s+sz <= 32) { cc = (cc << s) | c;      sz+= s; } \
@@ -79,18 +72,24 @@ typedef struct {
 } side_info_t;
 
 typedef struct {
-    side_info_t       cod_info[2][2];
-    mpeg_t            mpg;
-    long              frac_per_frame;
-    long              byte_per_frame;
-    long              slot_lag;
-    int               sideinfo_len;
-    int               mean_bits;
-    int               ResvSize;
-    int               channels;
-    int               rec_mono_mode;
-    int               granules;
-    long              samplerate;
+    side_info_t cod_info[2][2];
+    mpeg_t   mpg;
+    long     frac_per_frame;
+    long     byte_per_frame;
+    long     req_byte_per_frame;
+    long     slot_lag;
+    int      sideinfo_len;
+    int      mean_bits;
+    int      ResvSize;
+    int      channels;
+    int      granules;
+    long     src_samplerate;
+    long     samplerate;
+    short    *samp_buffer;
+    unsigned samp_per_frame;
+    int      flush_frames;
+    int      delay;
+    int      padding;
 } config_t;
 
 typedef struct {
@@ -118,7 +117,8 @@ struct huffcodebig {
 #define shft_n(x,n) ((x) >> n)
 #define SQRT        724 /* sqrt(2) * 512 */
 
-static short     mfbuf       [2*(1152+512)]      IBSS_ATTR; /*  3328 Bytes */
+static short     mfbuf       [2*(1152+512)]      IBSS_ATTR
+         /* for memcpy and 32-bit access */ MEM_ALIGN_ATTR; /*  3328 Bytes */
 static int       sb_data     [2][2][18][SBLIMIT] IBSS_ATTR; /* 13824 Bytes */
 static int       mdct_freq   [SAMPL2]            IBSS_ATTR; /*  2304 Bytes */
 static char      mdct_sign   [SAMPL2]            IBSS_ATTR; /*   576 Bytes */
@@ -171,12 +171,7 @@ static uint8_t   t16l        [256]               IBSS_ATTR;
 static uint8_t   t24l        [256]               IBSS_ATTR;
 static struct huffcodetab ht [HTN]               IBSS_ATTR;
 
-static unsigned pcm_chunk_size                   IBSS_ATTR;
-static unsigned samp_per_frame                   IBSS_ATTR;
-
 static config_t          cfg                     IBSS_ATTR;
-static char             *res_buffer;
-static int32_t           err                     IBSS_ATTR;
 static uint8_t           band_scale_f[22];
 
 static const uint8_t ht_count_const[2][2][16] =
@@ -848,42 +843,56 @@ static int  count_bit1 ( short *ix, uint32_t start, uint32_t end, int *bits );
 static int  count_bigv ( short *ix, uint32_t start, uint32_t end, int table0, int table1,
                   int *bits);
 
+static inline uint32_t encodeHeader( int padding, long bitr_id )
+{
+    /*
+     * MPEG header layout:
+     * AAAAAAAA AAABBCCD EEEEFFGH IIJJKLMM
+     * A (31-21) = frame sync
+     * B (20-19) = MPEG type
+     * C (18-17) = MPEG layer
+     * D (16)    = protection bit
+     * E (15-12) = bitrate index
+     * F (11-10) = samplerate index
+     * G (9)     = padding bit
+     * H (8)     = private bit
+     * I (7-6)   = channel mode
+     * J (5-4)   = mode extension (jstereo only)
+     * K (3)     = copyright bit
+     * L (2)     = original
+     * M (1-0)   = emphasis
+     */
+    return (0xffe00000           )  /* frame sync (AAAAAAAAA AAA) */
+         | (0x2             << 19)  /* mp3 type (upper):  1 (BB)  */
+         | (cfg.mpg.type    << 19)
+         | (0x1             << 17)  /* mp3 layer:        01 (CC)  */
+         | (0x1             << 16)  /* mp3 crc:           1 (D)   */
+         | (bitr_id         << 12)
+         | (cfg.mpg.smpl_id << 10)
+         | (padding         <<  9)
+         | (cfg.mpg.mode    <<  6)
+         | (0x1             <<  2); /* mp3 org:           1 (L)   */
+    /* no emphasis (bits 0-1) */
+}
+
+static long calcFrameSize(int bitr_id, long *frac)
+{
+    unsigned long v = bitr_index[cfg.mpg.type][bitr_id];
+    v = SAMPL2 * 16000 * v / (2 - cfg.mpg.type);
+    v /= cfg.samplerate;
+
+    if (frac)
+        *frac = v % 64;
+
+    return v / 64;
 
+}
 static void encodeSideInfo( side_info_t si[2][2] )
 {
-  int gr, ch, header;
+  int gr, ch;
   uint32_t  cc=0, sz=0;
 
-  /*
-   * MPEG header layout:
-   * AAAAAAAA AAABBCCD EEEEFFGH IIJJKLMM
-   * A (31-21) = frame sync
-   * B (20-19) = MPEG type
-   * C (18-17) = MPEG layer
-   * D (16)    = protection bit
-   * E (15-12) = bitrate index
-   * F (11-10) = samplerate index
-   * G (9)     = padding bit
-   * H (8)     = private bit
-   * I (7-6)   = channel mode
-   * J (5-4)   = mode extension (jstereo only)
-   * K (3)     = copyright bit
-   * L (2)     = original
-   * M (1-0)   = emphasis
-   */
-
-  header  = (0xfff00000) | /* frame sync (AAAAAAAAA AAA)
-                              mp3 type (upper):  1 (B)  */
-            (0x01 << 17) | /* mp3 layer:        01 (CC) */
-            ( 0x1 << 16) | /* mp3 crc:           1 (D)  */
-            ( 0x1 <<  2);  /* mp3 org:           1 (L)  */
-  header |= cfg.mpg.type    << 19;
-  header |= cfg.mpg.bitr_id << 12;
-  header |= cfg.mpg.smpl_id << 10;
-  header |= cfg.mpg.padding <<  9;
-  header |= cfg.mpg.mode    <<  6;
-  /* no emphasis (bits 0-1) */
-  putbits( header, 32 );
+  putbits( encodeHeader( cfg.mpg.padding, cfg.mpg.bitr_id ), 32 );
 
   if(cfg.mpg.type == 1)
   { /* MPEG1 */
@@ -1501,8 +1510,8 @@ static void iteration_loop(int *xr, side_info_t *si, int gr_cnt)
 
 
 /* returns sum_j=0^31 a[j]*cos(PI*j*(k+1/2)/32), 0<=k<32 */
-void window_subband1(short *wk, int sb0[SBLIMIT], int sb1[SBLIMIT]) ICODE_ATTR;
-void window_subband1(short *wk, int sb0[SBLIMIT], int sb1[SBLIMIT])
+static void ICODE_ATTR window_subband1(short *wk, int sb0[SBLIMIT],
+                                       int sb1[SBLIMIT])
 {
   int   k, i, u, v;
   short *wp, *x1, *x2;
@@ -1761,8 +1770,7 @@ void window_subband1(short *wk, int sb0[SBLIMIT], int sb1[SBLIMIT])
 #endif
 }
 
-void window_subband2(short *x1, int a[SBLIMIT]) ICODE_ATTR;
-void window_subband2(short *x1, int a[SBLIMIT])
+static void ICODE_ATTR window_subband2(short *x1, int a[SBLIMIT])
 {
   int   xr;
   short *wp = enwindow;
@@ -1879,8 +1887,7 @@ void window_subband2(short *x1, int a[SBLIMIT])
   xr = a[29];  a[29] += a[ 2];  a[ 2] -= xr;
 }
 
-void mdct_long(int *out, int *in) ICODE_ATTR;
-void mdct_long(int *out, int *in)
+static void ICODE_ATTR mdct_long(int *out, int *in)
 {
   int ct,st;
   int tc1, tc2, tc3, tc4, ts5, ts6, ts7, ts8;
@@ -1969,44 +1976,51 @@ static int find_samplerate_index(long freq, int *mp3_type)
     return i;
 }
 
-static bool init_mp3_encoder_engine(int sample_rate,
-                                    int num_channels,
-                                    int rec_mono_mode,
-                                    struct encoder_config *enc_cfg)
+static void mp3_encoder_reset(void)
+{
+    memset(&cfg.cod_info, 0, sizeof(cfg.cod_info));
+    memset(mfbuf        , 0, sizeof(mfbuf       ));
+    memset(mdct_freq    , 0, sizeof(mdct_freq   ));
+    memset(enc_data     , 0, sizeof(enc_data    ));
+    memset(sb_data      , 0, sizeof(sb_data     ));
+    memset(&CodedData   , 0, sizeof(CodedData   ));
+    cfg.slot_lag = 0;
+}
+
+static void mp3_encoder_init(unsigned long sample_rate, int num_channels,
+                             unsigned long bitrate)
 {
-    const bool stereo = num_channels > 1;
-    uint32_t avg_byte_per_frame;
-
-    cfg.channels      = stereo ? 2 : 1;
-    cfg.rec_mono_mode = rec_mono_mode;
-    cfg.mpg.mode      = stereo ? 0 : 3; /* 0=stereo, 3=mono */
-    cfg.mpg.smpl_id   = find_samplerate_index(sample_rate, &cfg.mpg.type);
-    cfg.samplerate    = sampr_index[cfg.mpg.type][cfg.mpg.smpl_id];
-    cfg.mpg.bitr_id   = find_bitrate_index(cfg.mpg.type,
-                                           enc_cfg->mp3_enc.bitrate,
-                                           stereo);
-    cfg.mpg.bitrate   = bitr_index[cfg.mpg.type][cfg.mpg.bitr_id];
-    cfg.mpg.num_bands = num_bands[stereo ? cfg.mpg.type : 2][cfg.mpg.bitr_id];
+    mp3_encoder_reset();
+
+    const bool stereo  = num_channels > 1;
+    cfg.channels       = stereo ? 2 : 1;
+    cfg.mpg.mode       = stereo ? 0 : 3; /* 0=stereo, 3=mono */
+    cfg.mpg.smpl_id    = find_samplerate_index(sample_rate, &cfg.mpg.type);
+    cfg.samplerate     = sampr_index[cfg.mpg.type][cfg.mpg.smpl_id];
+    cfg.src_samplerate = sample_rate;
+    cfg.mpg.bitr_id    = find_bitrate_index(cfg.mpg.type, bitrate, stereo);
+    cfg.mpg.bitrate    = bitr_index[cfg.mpg.type][cfg.mpg.bitr_id];
+    cfg.mpg.num_bands  = num_bands[stereo ? cfg.mpg.type : 2][cfg.mpg.bitr_id];
 
     if (cfg.mpg.type == 1)
     {
-        cfg.granules = 2;
-        pcm_chunk_size = PCM_CHUNK_SIZE1;
-        samp_per_frame = SAMP_PER_FRAME1;
+        cfg.granules       = 2;
+        cfg.samp_per_frame = 1152;
+        cfg.flush_frames   = 2;
     }
     else
     {
-        cfg.granules = 1;
-        pcm_chunk_size = PCM_CHUNK_SIZE2;
-        samp_per_frame = SAMP_PER_FRAME2;
+        cfg.granules       = 1;
+        cfg.samp_per_frame = 576;
+        cfg.flush_frames   = 3;
     }
 
+    cfg.delay   = 576-16;
+    cfg.padding = 3*576+16;
+
+    cfg.samp_buffer = mfbuf + 2*512;
+
     memcpy(scalefac, sfBand[cfg.mpg.smpl_id + 3*cfg.mpg.type], sizeof(scalefac));
-    memset(mfbuf     , 0              , sizeof(mfbuf     ));
-    memset(mdct_freq , 0              , sizeof(mdct_freq ));
-    memset(enc_data  , 0              , sizeof(enc_data  ));
-    memset(sb_data   , 0              , sizeof(sb_data   ));
-    memset(&CodedData, 0              , sizeof(CodedData ));
     memcpy(ca        , ca_const       , sizeof(ca        ));
     memcpy(cs        , cs_const       , sizeof(cs        ));
     memcpy(cx        , cx_const       , sizeof(cx        ));
@@ -2052,6 +2066,7 @@ static bool init_mp3_encoder_engine(int sample_rate,
     memcpy(t16l      , t16l_const     , sizeof(t16l      ));
     memcpy(t24l      , t24l_const     , sizeof(t24l      ));
     memcpy(ht        , ht_const       , sizeof(ht        ));
+    memset(band_scale_f, 0            , sizeof(band_scale_f));
 
     ht[ 0].table =  NULL;  ht[ 0].hlen = NULL; /* Apparently not used */
     ht[ 1].table =  t1HB;  ht[ 1].hlen =  t1l;
@@ -2071,90 +2086,14 @@ static bool init_mp3_encoder_engine(int sample_rate,
     ht[15].table = t15HB;  ht[15].hlen = t15l;
 
     /* Figure average number of 'bytes' per frame */
-    avg_byte_per_frame = SAMPL2 * 16000 * cfg.mpg.bitrate / (2 - cfg.mpg.type);
-    avg_byte_per_frame = avg_byte_per_frame / cfg.samplerate;
-    cfg.byte_per_frame = avg_byte_per_frame / 64;
-    cfg.frac_per_frame = avg_byte_per_frame & 63;
-    cfg.slot_lag       = 0;
+    cfg.byte_per_frame = calcFrameSize(cfg.mpg.bitr_id, &cfg.frac_per_frame);
     cfg.sideinfo_len   = 32 + (cfg.mpg.type ? (cfg.channels == 1 ? 136 : 256)
                                             : (cfg.channels == 1 ?  72 : 136));
 
-    return true;
+    cfg.req_byte_per_frame = ALIGN_UP(cfg.byte_per_frame + 1,
+                                      sizeof (uint32_t));
 }
 
-static inline void to_mono(uint16_t **samp)
-{
-    int16_t l = **samp;
-    int16_t r = *(*samp+1);
-    int32_t m;
-
-    switch(cfg.rec_mono_mode)
-    {
-        case 1:
-            /* mono = L */
-            m  = l;
-            break;
-        case 2:
-            /* mono = R */
-            m  = r;
-            break;
-        case 0:
-        default:
-            /* mono = (L+R)/2 */
-            m  = l + r + err;
-            err = m & 1;
-            m >>= 1;
-            break;
-    }
-    *(*samp)++ = (uint16_t)m;
-    *(*samp)++ = (uint16_t)m;
-} /* to_mono */
-
-static void to_mono_mm(void) ICODE_ATTR;
-static void to_mono_mm(void)
-{
-    /* |llllllllllllllll|rrrrrrrrrrrrrrrr| =>
-     * |mmmmmmmmmmmmmmmm|mmmmmmmmmmmmmmmm|
-     */
-    uint16_t *samp = &mfbuf[2*512];
-    uint16_t *samp_end = samp + 2*samp_per_frame;
-
-    do
-    {
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-        to_mono(&samp);
-    }
-    while (samp < samp_end);
-} /* to_mono_mm */
-
-#ifdef ROCKBOX_LITTLE_ENDIAN
-/* Swaps a frame to big endian */
-static inline void byte_swap_frame32(uint32_t *dst, uint32_t *src,
-                                     size_t size)
-{
-    uint32_t *src_end = SKIPBYTES(src, size);
-
-    do
-    {
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-        *dst++ = swap32(*src++);
-    }
-    while(src < src_end);
-} /* byte_swap_frame32 */
-#endif /* ROCKBOX_LITTLE_ENDIAN */
-
 static void set_scale_facs(int *mdct_freq)
 {
   unsigned int i, is, ie, k, s;
@@ -2188,12 +2127,10 @@ static void set_scale_facs(int *mdct_freq)
   }
 }
 
-static void encode_frame(char *buffer, struct enc_chunk_hdr *chunk)
-                             ICODE_ATTR;
-static void encode_frame(char *buffer, struct enc_chunk_hdr *chunk)
+static size_t ICODE_ATTR mp3_encoder_encode_frame(uint8_t *outbuf)
 {
-   int      gr, gr_cnt;
-   uint32_t max;
+    int      gr, gr_cnt;
+    uint32_t max;
 
     /* encode one mp3 frame in this loop */
     CodedData.bitpos = 0;
@@ -2211,28 +2148,6 @@ static void encode_frame(char *buffer, struct enc_chunk_hdr *chunk)
                        - cfg.sideinfo_len) / cfg.granules / cfg.channels
                        - 42; // reserved for scale_facs
 
-    /* shift out old samples */
-    memcpy(mfbuf, mfbuf + 2*cfg.granules*576, 4*512);
-
-    if (chunk->flags & CHUNKF_START_FILE)
-    {
-        /* prefix silent samples for encoder delay */
-        memset(mfbuf + 2*512, 0, ENC_DELAY_SIZE);
-        /* read new samples to iram for further processing */
-        memcpy(mfbuf + 2*512 + ENC_DELAY_SIZE/2,
-               buffer, pcm_chunk_size - ENC_DELAY_SIZE);
-        chunk->num_pcm = samp_per_frame - ENC_DELAY_SAMP;
-    }
-    else
-    {
-        /* read new samples to iram for further processing */
-        memcpy(mfbuf + 2*512, buffer, pcm_chunk_size);
-        chunk->num_pcm = samp_per_frame;
-    }
-
-    if (cfg.channels == 1)
-        to_mono_mm();
-
     cfg.ResvSize = 0;
     gr_cnt = cfg.granules * cfg.channels;
     CodedData.bitpos = cfg.sideinfo_len; /* leave space for mp3 header */
@@ -2366,264 +2281,398 @@ static void encode_frame(char *buffer, struct enc_chunk_hdr *chunk)
         }
     }
 
-    chunk->enc_size = cfg.byte_per_frame + cfg.mpg.padding;
+    /* shift out old samples */
+    memmove(mfbuf, mfbuf + 2*cfg.granules*576, 4*512);
 
     /* finish this chunk by adding sideinfo header data */
     CodedData.bitpos = 0;
     encodeSideInfo( cfg.cod_info );
 
-#ifdef ROCKBOX_BIG_ENDIAN
-    /* copy chunk to enc_buffer */
-    memcpy(chunk->enc_data, CodedData.bbuf, chunk->enc_size);
+    long size = cfg.byte_per_frame + cfg.mpg.padding;
+
+#ifdef ROCKBOX_LITTLE_ENDIAN
+    /* convert frame to big endian */
+    const uint32_t *src = CodedData.bbuf;
+    uint32_t *dst = (uint32_t *)outbuf;
+
+    for(long i = 0; i < size; i += sizeof(uint32_t))
+        *dst++ = swap32(*src++);
 #else
-    /* swap frame to big endian */
-    byte_swap_frame32((uint32_t *)chunk->enc_data, CodedData.bbuf, chunk->enc_size);
-#endif
-} /* encode_frame */
+    memcpy(outbuf, CodedData.bbuf, size);
+#endif /* ROCKBOX_LITTLE_ENDIAN */
 
-/* called very often - inline */
-static inline bool is_file_data_ok(struct enc_file_event_data *filed)
-{
-    return filed->rec_file >= 0 && (long)filed->chunk->flags >= 0;
-} /* is_event_ok */
+    return size;
+}
 
-static unsigned char mp3_data[16384] __attribute__((aligned(4)));
-static unsigned int  mp3_data_len; /* current data size in buffer */
 
-/* called very often - inline */
-static inline bool on_write_chunk(struct enc_file_event_data *data)
-{
-    if (!is_file_data_ok(data))
-        return false;
+/*======== Codec section ========*/
 
-    if (data->chunk->enc_data == NULL)
-    {
-#ifdef ROCKBOX_HAS_LOGF
-        ci->logf("mp3 enc: NULL data");
-#endif
-        return true;
-    }
+/* CRC code lovingly ripped from:
+ * github.com/CFR-maniac/lame/blob/master/libmp3lame/VbrTag.c */
 
-    /* if current chunk doesn't fit => write collected data */
-    if (mp3_data_len + data->chunk->enc_size > sizeof(mp3_data))
-    {
-        if (ci->write(data->rec_file, mp3_data,
-                    mp3_data_len) != (ssize_t)mp3_data_len)
-            return false;
+/* Lookup table for fast CRC computation
+ * See 'crc_update_lookup'
+ * Uses the polynomial x^16+x^15+x^2+1 */
+static const uint16_t crc16_lookup[256] ICONST_ATTR =
+{
+    0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
+    0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
+    0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
+    0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
+    0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
+    0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
+    0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
+    0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
+    0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
+    0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
+    0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
+    0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
+    0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
+    0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
+    0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
+    0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
+    0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
+    0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
+    0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
+    0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
+    0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
+    0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
+    0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
+    0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
+    0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
+    0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
+    0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
+    0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
+    0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
+    0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
+    0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
+    0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
+};
 
-        mp3_data_len = 0;
-    }
+static ssize_t header_size;
+static unsigned int mp3_crc16;
 
-    memcpy(mp3_data+mp3_data_len, data->chunk->enc_data,
-           data->chunk->enc_size);
+/* fast CRC-16 computation - uses table crc16_lookup 8*/
+static inline unsigned int crc_update_lookup(unsigned int value,
+                                             unsigned int crc)
+{
+    unsigned int tmp = crc ^ value;
+    crc = (crc >> 8) ^ crc16_lookup[tmp & 0xff];
+    return crc & 0xffff;
+}
 
-    mp3_data_len += data->chunk->enc_size;
+/* Calculate position of 'Info' header */
+static int get_info_offset(uint32_t header)
+{
+    uint32_t type = (header & (0x3 << 19)) >> 19;
+    uint32_t mode = (header & (0x3 << 6)) >> 6;
 
-    data->num_pcm_samples += data->chunk->num_pcm;
-    return true;
-} /* on_write_chunk */
+    return type == 3 ? (mode == 3 ? 21 : 36) : (mode == 3 ? 13 : 21);
+}
 
-static bool on_start_file(struct enc_file_event_data *data)
+/* Write very basic 'Info' header with delay, padding and a bit of
+ * miscellaneous info. */
+static bool write_info_header(bool first_encode)
 {
-    if ((data->chunk->flags & CHUNKF_ERROR) || *data->filename == '\0')
-        return false;
+    ssize_t size = cfg.byte_per_frame;
 
-    data->rec_file = ci->open(data->filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
+    /* By default the MP3 frame header for the info frame is the same as
+       unpadded audio frames */
+    uint32_t header = encodeHeader(0, cfg.mpg.bitr_id);
 
-    if (data->rec_file < 0)
-        return false;
+    int i = get_info_offset(header);
 
-    /* reset sample count */
-    data->num_pcm_samples = 0;
+    if (i + 8 + 36 > size)
+    {
+        /* The default frame size too small so find the smallest one that
+           may accomodate it by increasing the bit rate for this empty
+           MP3 frame */
+        int j;
+        for (j = cfg.mpg.bitr_id + 1; j < 15; j++)
+        {
+            size = calcFrameSize(j, NULL);
 
-    /* reset buffer write position */
-    mp3_data_len = 0;
+            if (size >= i + 8 + 36)
+                break;
+        }
 
-    return true;
-} /* on_start_file */
+        if (j >= 15)
+        {
+            /* Shouldn't really happen but... */
+            header_size = -1;
+            return true;
+        }
 
-static bool on_end_file(struct enc_file_event_data *data)
-{
-    if (data->rec_file < 0)
-        return false; /* file already closed, nothing more we can do */
+        header = encodeHeader(0, j);
+        /* Info offset won't change */
+    }
 
-    /* write the remaining mp3_data */
-    if (ci->write(data->rec_file, mp3_data, mp3_data_len)
-                   != (ssize_t)mp3_data_len)
-        return false;
+    uint8_t frame[size];
+    memset(frame, 0, size);
 
-    /* reset buffer write position */
-    mp3_data_len = 0;
+    frame[0] = header >> 24;
+    frame[1] = header >> 16;
+    frame[2] = header >>  8;
+    frame[3] = header >>  0;
 
-    /* always _try_ to write the file header, even on error */
-    if (ci->close(data->rec_file) != 0)
-        return false;
+    /* 'Info' header (CBR 'Xing') */
+    memcpy(&frame[i], "Info", 4);
 
-    data->rec_file = -1;
+    /* flags = 0; Info contains no other sections and is 8 bytes */
 
-    return true;
-} /* on_end_file */
+    /* Just mark the LAMEness to indicate header presence; we're not
+       actually _the_ LAME so 'rbshn' is the version we give */
+    memcpy(&frame[i + 8], "LAMErbshn", 9);
 
-static void on_rec_new_stream(struct enc_buffer_event_data *data)
-{
-    int num_frames = cfg.mpg.type == 1 ?
-        ENC_PADDING_FRAMES1 : ENC_PADDING_FRAMES2;
+    /* Fill-in some info about us
+     * reference: http://gabriel.mp3-tech.org/mp3infotag.html
+     */
 
-    if (data->flags & CHUNKF_END_FILE)
-    {
-        /* add silent frames to end - encoder will also be flushed for start
-           of next file if any */
-        memset(res_buffer, 0, pcm_chunk_size);
+    /* Revision + VBR method:
+     * [7:4] = Revision (0 ??)
+     * [3:0] = VBR method (CBR)
+     */
+    frame[i + 17] = (0 << 4) | (1 << 0);
 
-        /* the initial chunk given for the end is at enc_wr_index */
-        while (num_frames-- > 0)
-        {
-            data->chunk->enc_data = ENC_CHUNK_SKIP_HDR(data->chunk->enc_data,
-                                                       data->chunk);
+    /* If first frame since encoder reset is long gone (not unlikely in
+       prerecording), then the delay is long passed and no trimming done
+       at the start */
+    unsigned int delay = first_encode ? cfg.delay : 0;
+    unsigned int padding = cfg.padding;
 
-            encode_frame(res_buffer, data->chunk);
-            data->chunk->num_pcm = samp_per_frame;
+    /* Delay and padding:
+     * [23:12] = delay
+     * [11: 0] = padding
+     */
+    frame[i + 29] = delay >> 4;
+    frame[i + 30] = (delay << 4) | (padding >> 8);
+    frame[i + 31] = padding;
+
+    /* Misc:
+     * [7:6] = source frequency
+     * [  5] = unwise settings (of course not :)
+     * [4:2] = stereo mode (mono or stereo)
+     * [1:0] = noise shaping (who knows, 0)
+     */
+    uint8_t misc;
 
-            ci->enc_finish_chunk();
-            data->chunk = ci->enc_get_chunk();
-        }
-    }
-    else if (data->flags & CHUNKF_PRERECORD)
-    {
-        /* nothing to add and we cannot change prerecorded data */
-    }
-    else if (data->flags & CHUNKF_START_FILE)
-    {
-        /* starting fresh ... be sure to flush encoder first */
-        struct enc_chunk_hdr *chunk = ENC_CHUNK_HDR(res_buffer);
+    if (cfg.src_samplerate <= 32000)
+        misc = (0 << 6);
+    else if (cfg.src_samplerate <= 44100)
+        misc = (1 << 6);
+    else if (cfg.src_samplerate <= 48000)
+        misc = (2 << 6);
+    else /* > 48000 */
+        misc = (3 << 6);
 
-        chunk->flags    = 0;
-        chunk->enc_data = ENC_CHUNK_SKIP_HDR(chunk->enc_data, chunk);
+    if (cfg.channels > 1)
+        misc |= (1 << 2); /* Stereo */
 
-        while (num_frames-- > 0)
-        {
-            memset(chunk->enc_data, 0, pcm_chunk_size);
-            encode_frame(chunk->enc_data, chunk);
-        }
+    frame[i + 32] = misc;
+
+    if (ci->enc_stream_write(frame, size) != size)
+    {
+        ci->enc_stream_lseek(0, SEEK_SET);
+        header_size = -1;
+        return false;
     }
-} /* on_rec_new_stream */
 
-static void enc_events_callback(enum enc_events event, void *data)
+    header_size = size;
+    return true;
+}
+
+static inline int on_stream_data(struct enc_chunk_data *data)
 {
-    switch (event)
+    ssize_t size = data->hdr.size;
+
+    if (header_size > 0)
     {
-    case ENC_WRITE_CHUNK:
-        if (on_write_chunk((struct enc_file_event_data *)data))
-            return;
+        /* Header is layed-down; keep running CRC of audio data */
+        uint8_t *p = data->data;
+        uint8_t *p_end = p + size;
 
-        break;
+        while (p < p_end)
+            mp3_crc16 = crc_update_lookup(*p++, mp3_crc16);
+    }
 
-    case ENC_START_FILE:
-        if (on_start_file((struct enc_file_event_data *)data))
-            return;
+    if (ci->enc_stream_write(data->data, size) != size)
+        return -1;
 
-        break;
+    return 0;
+}
 
-    case ENC_END_FILE:
-         if (on_end_file((struct enc_file_event_data *)data))
-            return;
+static int on_stream_start(struct enc_chunk_file *file)
+{
+    mp3_crc16 = 0x0000;
 
-         break;
+    if (!write_info_header(file->hdr.aux0))
+        return -1;
 
-    case ENC_REC_NEW_STREAM:
-        on_rec_new_stream((struct enc_buffer_event_data *)data);
-        return;
+    return 0;
+}
 
-    default:
-        return;
-    }
+static int on_stream_end(union enc_chunk_hdr *hdr)
+{
+    ssize_t size = header_size;
 
-    /* Something failed above. Signal error back to core. */
-    ((struct enc_file_event_data *)data)->chunk->flags |= CHUNKF_ERROR;
-} /* enc_events_callback */
+    if (size <= 0)
+        return 0; /* No header possible/none yet written */
 
-static bool enc_init(void)
-{
-    struct enc_inputs     inputs;
-    struct enc_parameters params;
-
-    if (ci->enc_get_inputs         == NULL ||
-        ci->enc_set_parameters     == NULL ||
-        ci->enc_get_chunk          == NULL ||
-        ci->enc_finish_chunk       == NULL ||
-        ci->enc_get_pcm_data       == NULL ||
-        ci->enc_unget_pcm_data     == NULL )
-        return false;
+    /* Update audio CRC and header CRC */
+    uint8_t frame[size];
 
-    ci->enc_get_inputs(&inputs);
+    /* Won't fail this since it could still be useable if some decoder
+       plays loose with the CRC info (like Rockbox :) */
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0 ||
+        ci->enc_stream_read(frame, size) != size)
+        return 0;
 
-    if (inputs.config->afmt != AFMT_MPA_L3)
-        return false;
+    uint32_t header = (frame[0] << 24) | (frame[1] << 16) |
+                      (frame[2] <<  8) | (frame[3] <<  0);
+    int i = get_info_offset(header); /* Get 'Info' header */
 
-    init_mp3_encoder_engine(inputs.sample_rate, inputs.num_channels,
-                            inputs.rec_mono_mode, inputs.config);
+    /* 'Info' header = 8 bytes */
 
-    err = 0;
+    /* Fill-in audio data CRC16 */
 
-    /* configure the buffer system */
-    params.afmt            = AFMT_MPA_L3;
-    params.chunk_size      = cfg.byte_per_frame + 1;
-    params.enc_sample_rate = cfg.samplerate;
-    /* need enough reserved bytes to hold one frame of pcm samples + hdr
-       for padding and flushing */
-    params.reserve_bytes   = ENC_CHUNK_HDR_SIZE + pcm_chunk_size;
-    params.events_callback = enc_events_callback;
-    ci->enc_set_parameters(&params);
+    /* On error, fixing data CRC would require scanning file since it
+       has probably dropped something we tried to write and the likely
+       reason is that the disk filled; just leave it 0 in that case. */
+    if (!hdr->err)
+    {
+        frame[i + 40] = mp3_crc16 >> 8;
+        frame[i + 41] = mp3_crc16;
+    }
 
-    res_buffer             = params.reserve_buffer;
+    /* Fill-in header CRC16 */
+    unsigned int hdr_crc16 = 0x0000;
+    for (int j = 0; j < i + 42; j++)
+        hdr_crc16 = crc_update_lookup(frame[j], hdr_crc16);
 
-#ifdef CPU_COLDFIRE
-    asm volatile ("move.l #0, %macsr"); /* integer mode */
-#endif
+    frame[i + 42] = hdr_crc16 >> 8;
+    frame[i + 43] = hdr_crc16;
 
-    return true;
-} /* enc_init */
+    /* Update file */
+    if (ci->enc_stream_lseek(0, SEEK_SET) == 0)
+        ci->enc_stream_write(frame, size);
+
+    return 0;
+}
 
 /* this is the codec entry point */
 enum codec_status codec_main(enum codec_entry_call_reason reason)
 {
-    if (reason == CODEC_LOAD) {
-        if (!enc_init())
-            return CODEC_ERROR;
-    }
-    else if (reason == CODEC_UNLOAD) {
-        /* reset parameters to initial state */
-        ci->enc_set_parameters(NULL);
-    }
-
+#ifdef CPU_COLDFIRE
+    if (reason == CODEC_LOAD)
+        asm volatile ("move.l #0, %macsr"); /* integer mode */
+#endif
     return CODEC_OK;
+    (void)reason;
 }
 
 /* this is called for each file to process */
 enum codec_status codec_run(void)
 {
+    mp3_encoder_reset();
+    uint32_t first = 1;
+
+    /* Needs to do stream finishing steps to flush-out all samples */
+    int frames_rem = -1; /* -1 = indeterminate */
+
+    enum { GETBUF_ENC, GETBUF_PCM } getbuf = GETBUF_ENC;
+    struct enc_chunk_data *data = NULL;
+
     /* main encoding loop */
-    while(ci->get_command(NULL) != CODEC_ACTION_HALT)
+    while (frames_rem)
     {
-        char *buffer = buffer = ci->enc_get_pcm_data(pcm_chunk_size);
-        struct enc_chunk_hdr *chunk;
+        intptr_t param;
+        enum codec_command_action action = ci->get_command(&param);
 
-        if(buffer == NULL)
-            continue;
+        if (action != CODEC_ACTION_NULL)
+        {
+            if (action != CODEC_ACTION_STREAM_FINISH)
+                break;
 
-        chunk           = ci->enc_get_chunk();
-        chunk->enc_data = ENC_CHUNK_SKIP_HDR(chunk->enc_data, chunk);
+            if (frames_rem < 0)
+                frames_rem = cfg.flush_frames;
 
-        encode_frame(buffer, chunk);
+            /* Reply with required space */
+            *(size_t *)param = cfg.req_byte_per_frame*frames_rem;
+        }
 
-        if (chunk->num_pcm < samp_per_frame)
+        /* First obtain output buffer; when available, get PCM data */
+        switch (getbuf)
         {
-            ci->enc_unget_pcm_data(pcm_chunk_size - chunk->num_pcm*4);
-            chunk->num_pcm = samp_per_frame;
+        case GETBUF_ENC:
+            if (!(data = ci->enc_encbuf_get_buffer(cfg.req_byte_per_frame)))
+                continue;
+            getbuf = GETBUF_PCM;
+        case GETBUF_PCM:
+            if (LIKELY(frames_rem < 0))
+            {
+                /* Encoding audio */
+                int count = cfg.samp_per_frame;
+                if (!ci->enc_pcmbuf_read(cfg.samp_buffer, count))
+                    continue;
+
+                ci->enc_pcmbuf_advance(cfg.samp_per_frame);
+
+                if (cfg.channels == 1)
+                {
+                    /* Interleave the mono samples to stereo as required by
+                       encoder */
+                    uint16_t *src = cfg.samp_buffer + count;
+                    uint32_t *dst = (uint32_t *)(src + count);
+
+                    for (int i = count; i > 0; i--)
+                        { uint32_t s = *--src; *--dst = s | (s << 16); }
+                }
+            }
+            else
+            {
+                /* Flushing encoder */
+                memset(cfg.samp_buffer, 0, cfg.samp_per_frame*4);
+                frames_rem--;
+            }
+            getbuf = GETBUF_ENC;
         }
 
-        ci->enc_finish_chunk();
+        data->hdr.aux0 = first;
+        first = 0;
+        data->hdr.size = mp3_encoder_encode_frame(data->data);
+        data->pcm_count = cfg.samp_per_frame;
+        ci->enc_encbuf_finish_buffer();
     }
 
     return CODEC_OK;
 }
+
+/* this is called by recording system */
+int ICODE_ATTR enc_callback(enum enc_callback_reason reason,
+                            void *params)
+{
+    if (LIKELY(reason == ENC_CB_STREAM))
+    {
+        switch (((union enc_chunk_hdr *)params)->type)
+        {
+        case CHUNK_T_DATA:
+            return on_stream_data(params);
+        case CHUNK_T_STREAM_START:
+            return on_stream_start(params);
+        case CHUNK_T_STREAM_END:
+            return on_stream_end(params);
+        }
+    }
+    else if (reason == ENC_CB_INPUTS)
+    {
+        struct enc_inputs *inputs = params;
+
+        mp3_encoder_init(inputs->sample_rate, inputs->num_channels,
+                         inputs->config->mp3_enc.bitrate);
+
+        /* Return the actual configuration */
+        inputs->enc_sample_rate = cfg.samplerate;
+    }
+
+    return 0;
+}
diff --git a/lib/rbcodec/codecs/wav_enc.c b/lib/rbcodec/codecs/wav_enc.c
index 01d0f79bcf..71bb652374 100644
--- a/lib/rbcodec/codecs/wav_enc.c
+++ b/lib/rbcodec/codecs/wav_enc.c
@@ -8,6 +8,7 @@
  * $Id$
  *
  * Copyright (C) 2006 Antonius Hellmann
+ * Copyright (C) 2006-2013 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -40,12 +41,12 @@ struct riff_header
     uint16_t block_align;     /* 20h - num_channels*bits_per_samples/8   */
     uint16_t bits_per_sample; /* 22h - 8=8 bits, 16=16 bits, etc.        */
     /* Not for audio_format=1 (PCM) */
-/*  unsigned short extra_param_size;   24h - size of extra data          */
-/*  unsigned char  *extra_params; */
+/*  uint16_t extra_param_size;   24h - size of extra data                */
+/*  uint8_t  extra_params[extra_param_size];                             */
     /* data header */
     uint8_t  data_id[4];      /* 24h - "data" */
     uint32_t data_size;       /* 28h - num_samples*num_channels*bits_per_sample/8 */
-/*  unsigned char  *data;              2ch - actual sound data */
+/*  uint8_t  data[data_size];    2Ch - actual sound data */
 } __attribute__((packed));
 
 #define RIFF_FMT_HEADER_SIZE       12 /* format -> format_size */
@@ -55,19 +56,17 @@ struct riff_header
 #define PCM_DEPTH_BYTES             2
 #define PCM_DEPTH_BITS             16
 #define PCM_SAMP_PER_CHUNK       2048
-#define PCM_CHUNK_SIZE          (PCM_SAMP_PER_CHUNK*4)
 
-static int      num_channels IBSS_ATTR;
-static int      rec_mono_mode IBSS_ATTR;
+static int num_channels;
 static uint32_t sample_rate;
-static uint32_t enc_size;
-static int32_t  err          IBSS_ATTR;
+static size_t frame_size;
+static size_t data_size;
 
-static const struct riff_header riff_header =
+static const struct riff_header riff_template_header =
 {
     /* "RIFF" header */
     { 'R', 'I', 'F', 'F' },         /* riff_id          */
-    0,                              /* riff_size   (*)  */
+    0,                              /* riff_size    (*) */
     /* format header */
     { 'W', 'A', 'V', 'E' },         /* format           */
     { 'f', 'm', 't', ' ' },         /* format_id        */
@@ -82,305 +81,164 @@ static const struct riff_header riff_header =
     /* data header */
     { 'd', 'a', 't', 'a' },         /* data_id          */
     0                               /* data_size    (*) */
-    /* (*) updated during ENC_END_FILE event */
+    /* (*) updated when finalizing stream */
 };
 
-/* called version often - inline */
-static inline bool is_file_data_ok(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool is_file_data_ok(struct enc_file_event_data *data)
+static inline void frame_htole(uint32_t *p, size_t size)
 {
-    return data->rec_file >= 0 && (long)data->chunk->flags >= 0;
-} /* is_file_data_ok */
-
-/* called version often - inline */
-static inline bool on_write_chunk(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool on_write_chunk(struct enc_file_event_data *data)
-{
-    if (!is_file_data_ok(data))
-        return false;
-
-    if (data->chunk->enc_data == NULL)
+#ifdef ROCKBOX_BIG_ENDIAN
+    /* Byte-swap samples, stereo or mono */
+    do
     {
-#ifdef ROCKBOX_HAS_LOGF
-        ci->logf("wav enc: NULL data");
-#endif
-        return true;
+        uint32_t t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
+        t = swap_odd_even32(*p); *p++ = t;
     }
+    while (size -= 8 * 2 * PCM_DEPTH_BYTES);
+#endif /* ROCKBOX_BIG_ENDIAN */
+    (void)p; (void)size;
+}
 
-    if (ci->write(data->rec_file, data->chunk->enc_data,
-                  data->chunk->enc_size) != (ssize_t)data->chunk->enc_size)
-        return false;
-
-    data->num_pcm_samples += data->chunk->num_pcm;
-    return true;
-} /* on_write_chunk */
-
-static bool on_start_file(struct enc_file_event_data *data)
+static int on_stream_data(struct enc_chunk_data *data)
 {
-    if ((data->chunk->flags & CHUNKF_ERROR) || *data->filename == '\0')
-        return false;
+    size_t size = data->hdr.size;
+
+    if (ci->enc_stream_write(data->data, size) != (ssize_t)size)
+        return -1;
 
-    data->rec_file = ci->open(data->filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
+    data_size += size;
 
-    if (data->rec_file < 0)
-        return false;
+    return 0;
+}
 
+static int on_stream_start(void)
+{
     /* reset sample count */
-    data->num_pcm_samples = 0;
+    data_size = 0;
 
     /* write template header */
-    if (ci->write(data->rec_file, &riff_header, sizeof (riff_header))
-            != sizeof (riff_header))
-    {
-        return false;
-    }
+    if (ci->enc_stream_write(&riff_template_header, sizeof (struct riff_header))
+            != sizeof (struct riff_header))
+        return -1;
 
-    data->new_enc_size += sizeof (riff_header);
-    return true;
-} /* on_start_file */
+    return 0;
+}
 
-static bool on_end_file(struct enc_file_event_data *data)
+static int on_stream_end(union enc_chunk_hdr *hdr)
 {
     /* update template header */
-    struct riff_header hdr;
-    uint32_t data_size;
-
-    if (data->rec_file < 0)
-        return false; /* file already closed, nothing more we can do */
+    struct riff_header riff;
 
-    /* always _try_ to write the file header, even on error */
-    if ((ci->lseek(data->rec_file, 0, SEEK_SET)) ||
-        (ci->read(data->rec_file, &hdr, sizeof (hdr)) != sizeof (hdr)))
+    if (hdr->err)
     {
-        return false;
+        /* Called for stream error; get correct data size */
+        ssize_t size = ci->enc_stream_lseek(0, SEEK_END);
+
+        if (size > (ssize_t)sizeof (riff))
+            data_size = size - sizeof (riff);
     }
 
-    data_size = data->num_pcm_samples*num_channels*PCM_DEPTH_BYTES;
+    if (ci->enc_stream_lseek(0, SEEK_SET) ||
+        ci->enc_stream_read(&riff, sizeof (riff)) != sizeof (riff))
+        return -1;
 
     /* "RIFF" header */
-    hdr.riff_size    = htole32(RIFF_FMT_HEADER_SIZE + RIFF_FMT_DATA_SIZE
-                               + RIFF_DATA_HEADER_SIZE + data_size);
+    riff.riff_size = htole32(RIFF_FMT_HEADER_SIZE + RIFF_FMT_DATA_SIZE
+                             + RIFF_DATA_HEADER_SIZE + data_size);
 
     /* format data */
-    hdr.num_channels = htole16(num_channels);
-    hdr.sample_rate  = htole32(sample_rate);
-    hdr.byte_rate    = htole32(sample_rate*num_channels* PCM_DEPTH_BYTES);
-    hdr.block_align  = htole16(num_channels*PCM_DEPTH_BYTES);
+    riff.num_channels = htole16(num_channels);
+    riff.sample_rate = htole32(sample_rate);
+    riff.byte_rate = htole32(sample_rate*num_channels*PCM_DEPTH_BYTES);
+    riff.block_align = htole16(num_channels*PCM_DEPTH_BYTES);
 
     /* data header */
-    hdr.data_size    = htole32(data_size);
+    riff.data_size = htole32(data_size);
 
-    if (ci->lseek(data->rec_file, 0, SEEK_SET) != 0 ||
-        ci->write(data->rec_file, &hdr, sizeof (hdr)) != sizeof (hdr) ||
-        ci->close(data->rec_file) != 0)
-    {
-        return false;
-    }
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0)
+        return -2;
 
-    data->rec_file = -1;
+    if (ci->enc_stream_write(&riff, sizeof (riff)) != sizeof (riff))
+        return -3;
 
-    return true;
-} /* on_end_file */
+    return 0;
+}
 
-static void enc_events_callback(enum enc_events event, void *data)
-                                    ICODE_ATTR;
-static void enc_events_callback(enum enc_events event, void *data)
+/* this is the codec entry point */
+enum codec_status codec_main(enum codec_entry_call_reason reason)
 {
-    switch (event)
-    {
-    case ENC_WRITE_CHUNK:
-        if (on_write_chunk((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_START_FILE:
-        if (on_start_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_END_FILE:
-        if (on_end_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    default:
-        return;
-    }
-
-    /* Something failed above. Signal error back to core. */
-    ((struct enc_file_event_data *)data)->chunk->flags |= CHUNKF_ERROR;
-} /* enc_events_callback */
+    return CODEC_OK;
+    (void)reason;
+}
 
-/* convert native pcm samples to wav format samples */
-static inline void sample_to_mono(uint32_t **src, uint32_t **dst)
+/* this is called for each file to process */
+enum codec_status ICODE_ATTR codec_run(void)
 {
-    int32_t lr1, lr2;
+    enum { GETBUF_ENC, GETBUF_PCM } getbuf = GETBUF_ENC;
+    struct enc_chunk_data *data = NULL;
 
-    switch(rec_mono_mode)
+    /* main encoding loop */
+    while (1)
     {
-        case 1:
-            /* mono = L */
-            lr1 = *(*src)++;
-            lr1 = lr1 >> 16;
-            lr2 = *(*src)++;
-            lr2 = lr2 >> 16;
-            break;
-        case 2:
-            /* mono = R */
-            lr1 = *(*src)++;
-            lr1 = (uint16_t)lr1;
-            lr2 = *(*src)++;
-            lr2 = (uint16_t)lr2;
-            break;
-        case 0:
-        default:
-            /* mono = (L+R)/2 */
-            lr1 = *(*src)++;
-            lr1 = (int16_t)lr1 + (lr1 >> 16) + err;
-            err = lr1 & 1;
-            lr1 >>= 1;
-
-            lr2 = *(*src)++;
-            lr2 = (int16_t)lr2 + (lr2 >> 16) + err;
-            err = lr2 & 1;
-            lr2 >>= 1;
+        enum codec_command_action action = ci->get_command(NULL);
+
+        if (action != CODEC_ACTION_NULL)
             break;
-    }
-    *(*dst)++ = htole32((lr2 << 16) | (uint16_t)lr1);
-} /* sample_to_mono */
 
-static void chunk_to_wav_format(uint32_t *src, uint32_t *dst) ICODE_ATTR;
-static void chunk_to_wav_format(uint32_t *src, uint32_t *dst)
-{
-    if (num_channels == 1)
-    {
-        /* On big endian:
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr|
-         *  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr| =>
-         *  |mmmmmmmmMMMMMMMM|mmmmmmmmMMMMMMMM|
-         *
-         * On little endian:
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR|
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR| =>
-         *  |mmmmmmmmMMMMMMMM|mmmmmmmmMMMMMMMM|
-         */
-        uint32_t *src_end = src + PCM_SAMP_PER_CHUNK;
-
-        do
+        /* First obtain output buffer; when available, get PCM data */
+        switch (getbuf)
         {
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
-            sample_to_mono(&src, &dst);
+        case GETBUF_ENC:
+            if (!(data = ci->enc_encbuf_get_buffer(frame_size)))
+                continue;
+            getbuf = GETBUF_PCM;
+        case GETBUF_PCM:
+            if (!ci->enc_pcmbuf_read(data->data, PCM_SAMP_PER_CHUNK))
+                continue;
+            getbuf = GETBUF_ENC;
         }
-        while (src < src_end);
-    }
-    else
-    {
-#ifdef ROCKBOX_BIG_ENDIAN
-        /*  |LLLLLLLLllllllll|RRRRRRRRrrrrrrrr| =>
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR|
-         */
-        uint32_t *src_end = src + PCM_SAMP_PER_CHUNK;
 
-        do
-        {
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-            *dst++ = swap_odd_even32(*src++);
-        }
-        while (src < src_end);
-#else
-        /*  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR| =>
-         *  |llllllllLLLLLLLL|rrrrrrrrRRRRRRRR|
-         */
-        ci->memcpy(dst, src, PCM_CHUNK_SIZE);
-#endif
-    }
-} /* chunk_to_wav_format */
+        data->hdr.size = frame_size;
+        data->pcm_count = PCM_SAMP_PER_CHUNK;
 
-static bool init_encoder(void)
-{
-    struct enc_inputs     inputs;
-    struct enc_parameters params;
-
-    if (ci->enc_get_inputs         == NULL ||
-        ci->enc_set_parameters     == NULL ||
-        ci->enc_get_chunk          == NULL ||
-        ci->enc_finish_chunk       == NULL ||
-        ci->enc_get_pcm_data       == NULL )
-        return false;
-
-    ci->enc_get_inputs(&inputs);
-
-    if (inputs.config->afmt != AFMT_PCM_WAV)
-        return false;
-
-    sample_rate  = inputs.sample_rate;
-    num_channels = inputs.num_channels;
-    rec_mono_mode = inputs.rec_mono_mode;
-    err          = 0;
-
-    /* configure the buffer system */
-    params.afmt            = AFMT_PCM_WAV;
-    enc_size               = PCM_CHUNK_SIZE*inputs.num_channels / 2;
-    params.chunk_size      = enc_size;
-    params.enc_sample_rate = sample_rate;
-    params.reserve_bytes   = 0;
-    params.events_callback = enc_events_callback;
-    ci->enc_set_parameters(&params);
-
-    return true;
-} /* init_encoder */
+        frame_htole((uint32_t *)data->data, frame_size);
 
-/* this is the codec entry point */
-enum codec_status codec_main(enum codec_entry_call_reason reason)
-{
-    if (reason == CODEC_LOAD) {
-        if (!init_encoder())
-            return CODEC_ERROR;
-    }
-    else if (reason == CODEC_UNLOAD) {
-        /* reset parameters to initial state */
-        ci->enc_set_parameters(NULL);
+        ci->enc_pcmbuf_advance(PCM_SAMP_PER_CHUNK);
+        ci->enc_encbuf_finish_buffer();
     }
 
     return CODEC_OK;
 }
 
-/* this is called for each file to process */
-enum codec_status codec_run(void)
+/* this is called by recording system */
+int ICODE_ATTR enc_callback(enum enc_callback_reason reason,
+                            void *params)
 {
-    /* main encoding loop */
-    while(ci->get_command(NULL) != CODEC_ACTION_HALT)
+    if (LIKELY(reason == ENC_CB_STREAM))
     {
-        uint32_t *src = (uint32_t *)ci->enc_get_pcm_data(PCM_CHUNK_SIZE);
-        struct enc_chunk_hdr *chunk;
-
-        if(src == NULL)
-            continue;
-
-        chunk           = ci->enc_get_chunk();
-        chunk->enc_size = enc_size;
-        chunk->num_pcm  = PCM_SAMP_PER_CHUNK;
-        chunk->enc_data = ENC_CHUNK_SKIP_HDR(chunk->enc_data, chunk);
-
-        chunk_to_wav_format(src, (uint32_t *)chunk->enc_data);
-
-        ci->enc_finish_chunk();
+        switch (((union enc_chunk_hdr *)params)->type)
+        {
+        case CHUNK_T_DATA:
+            return on_stream_data(params);
+        case CHUNK_T_STREAM_START:
+            return on_stream_start();
+        case CHUNK_T_STREAM_END:
+            return on_stream_end(params);
+        }
+    }
+    else if (reason == ENC_CB_INPUTS)
+    {
+        struct enc_inputs *inputs = params;
+        sample_rate = inputs->sample_rate;
+        num_channels = inputs->num_channels;
+        frame_size = PCM_SAMP_PER_CHUNK*PCM_DEPTH_BYTES*num_channels;
     }
 
-    return CODEC_OK;
+    return 0;
 }
diff --git a/lib/rbcodec/codecs/wavpack_enc.c b/lib/rbcodec/codecs/wavpack_enc.c
index 1fae2d46a7..864012b4cd 100644
--- a/lib/rbcodec/codecs/wavpack_enc.c
+++ b/lib/rbcodec/codecs/wavpack_enc.c
@@ -8,6 +8,7 @@
  * $Id$
  *
  * Copyright (C) 2006 Antonius Hellmann
+ * Copyright (C) 2006-2013 Michael Sevakis
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -47,29 +48,39 @@ struct riff_header
     uint16_t block_align;     /* 20h - num_channels*bits_per_samples/8   */
     uint16_t bits_per_sample; /* 22h - 8=8 bits, 16=16 bits, etc.        */
     /* Not for audio_format=1 (PCM) */
-/*  unsigned short extra_param_size;   24h - size of extra data                */
-/*  unsigned char  *extra_params; */
+/*  uint16_t extra_param_size;   24h - size of extra data                */
+/*  uint8_t  extra_params[extra_param_size];                             */
     /* data header */
     uint8_t  data_id[4];      /* 24h - "data" */
     uint32_t data_size;       /* 28h - num_samples*num_channels*bits_per_sample/8 */
-/*  unsigned char  *data;              2ch - actual sound data */
+/*  uint8_t  data[data_size];    2Ch - actual sound data */
 } __attribute__((packed));
 
 #define RIFF_FMT_HEADER_SIZE   12 /* format -> format_size */
 #define RIFF_FMT_DATA_SIZE     16 /* audio_format -> bits_per_sample */
 #define RIFF_DATA_HEADER_SIZE   8 /* data_id -> data_size */
 
+struct wvpk_chunk_data
+{
+    struct enc_chunk_data ckhdr;  /* The base data chunk header */
+    WavpackHeader         wphdr;  /* The block wavpack info */
+    uint8_t               data[]; /* Encoded audio data */
+};
+
 #define PCM_DEPTH_BITS         16
 #define PCM_DEPTH_BYTES         2
 #define PCM_SAMP_PER_CHUNK   5000
-#define PCM_CHUNK_SIZE      (4*PCM_SAMP_PER_CHUNK)
 
 /** Data **/
-static int8_t input_buffer[PCM_CHUNK_SIZE*2]     IBSS_ATTR;
-static WavpackConfig config                      IBSS_ATTR;
+static int32_t input_buffer[PCM_SAMP_PER_CHUNK*2] IBSS_ATTR;
+
+static WavpackConfig config IBSS_ATTR;
 static WavpackContext *wpc;
-static int32_t data_size, input_size, input_step IBSS_ATTR;
-static int32_t err                               IBSS_ATTR;
+static uint32_t sample_rate;
+static int num_channels;
+static uint32_t total_samples;
+static size_t out_reqsize;
+static size_t frame_size;
 
 static const WavpackMetadataHeader wvpk_mdh =
 {
@@ -77,7 +88,7 @@ static const WavpackMetadataHeader wvpk_mdh =
     sizeof (struct riff_header) / sizeof (uint16_t),
 };
 
-static const struct riff_header riff_header =
+static const struct riff_header riff_template_header =
 {
     /* "RIFF" header */
     { 'R', 'I', 'F', 'F' },         /* riff_id          */
@@ -96,157 +107,75 @@ static const struct riff_header riff_header =
     /* data header */
     { 'd', 'a', 't', 'a' },         /* data_id          */
     0                               /* data_size    (*) */
-    /* (*) updated during ENC_END_FILE event */
+    /* (*) updated when finalizing stream */
 };
 
-static inline void sample_to_int32_mono(int32_t **src, int32_t **dst)
-{
-    int32_t t = *(*src)++;
-    /* endianness irrelevant */
-    t = (int16_t)t + (t >> 16) + err;
-    err = t & 1;
-    *(*dst)++ = t >> 1;
-} /* sample_to_int32_mono */
-
-static inline void sample_to_int32_stereo(int32_t **src, int32_t **dst)
+static inline void sample_to_int32(int32_t **dst, int32_t **src)
 {
-    int32_t t = *(*src)++;
+    uint32_t t = *(*src)++;
 #ifdef ROCKBOX_BIG_ENDIAN
-    *(*dst)++ = t >> 16, *(*dst)++ = (int16_t)t;
+    *(*dst)++ = (int32_t)t >> 16;
+    *(*dst)++ = (int16_t)t;
 #else
-    *(*dst)++ = (int16_t)t, *(*dst)++ = t >> 16;
+    *(*dst)++ = (int16_t)t;
+    *(*dst)++ = (int32_t)t >> 16;
 #endif
-} /* sample_to_int32_stereo */
+}
 
-static void chunk_to_int32(int32_t *src) ICODE_ATTR;
-static void chunk_to_int32(int32_t *src)
+static void ICODE_ATTR input_buffer_to_int32(size_t size)
 {
-    int32_t *src_end, *dst;
-#ifdef USE_IRAM
-    /* copy to IRAM before converting data */
-    dst     = (int32_t *)input_buffer + PCM_SAMP_PER_CHUNK;
-    src_end = dst + PCM_SAMP_PER_CHUNK;
-
-    memcpy(dst, src, PCM_CHUNK_SIZE);
-
-    src = dst;
-#else
-    src_end = src + PCM_SAMP_PER_CHUNK;
-#endif
-
-    dst = (int32_t *)input_buffer;
+    int32_t *dst = input_buffer;
+    int32_t *src = input_buffer + PCM_SAMP_PER_CHUNK;
 
-    if (config.num_channels == 1)
+    do
     {
-        /*
-         *  |llllllllllllllll|rrrrrrrrrrrrrrrr| =>
-         *  |mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm|
-         */
-        do
-        {
-            /* read 10 longs and write 10 longs */
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-            sample_to_int32_mono(&src, &dst);
-        }
-        while(src < src_end);
-
-        return;
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
+        sample_to_int32(&dst, &src);
     }
-    else
-    {
-        /*
-         *  |llllllllllllllll|rrrrrrrrrrrrrrrr| =>
-         *  |llllllllllllllllllllllllllllllll|rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr|
-         */
-        do
-        {
-            /* read 10 longs and write 20 longs */
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-            sample_to_int32_stereo(&src, &dst);
-        }
-        while (src < src_end);
-
-        return;
-    }
-} /* chunk_to_int32 */
-
-/* called very often - inline */
-static inline bool is_file_data_ok(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool is_file_data_ok(struct enc_file_event_data *data)
-{
-    return data->rec_file >= 0 && (long)data->chunk->flags >= 0;
-} /* is_file_data_ok */
+    while (size -= 10 * 2 * PCM_DEPTH_BYTES);
+}
 
-/* called very often - inline */
-static inline bool on_write_chunk(struct enc_file_event_data *data) ICODE_ATTR;
-static inline bool on_write_chunk(struct enc_file_event_data *data)
+static int on_stream_data(struct wvpk_chunk_data *wpdata)
 {
-    if (!is_file_data_ok(data))
-        return false;
-
-    if (data->chunk->enc_data == NULL)
-    {
-#ifdef ROCKBOX_HAS_LOGF
-        ci->logf("wvpk enc: NULL data");
-#endif
-        return true;
-    }
-
     /* update timestamp (block_index) */
-    ((WavpackHeader *)data->chunk->enc_data)->block_index =
-            htole32(data->num_pcm_samples);
+    wpdata->wphdr.block_index = htole32(total_samples);
 
-    if (ci->write(data->rec_file, data->chunk->enc_data,
-                  data->chunk->enc_size) != (ssize_t)data->chunk->enc_size)
-        return false;
+    size_t size = wpdata->ckhdr.hdr.size;
+    if (ci->enc_stream_write(wpdata->ckhdr.data, size) != (ssize_t)size)
+        return -1;
 
-    data->num_pcm_samples += data->chunk->num_pcm;
-    return true;
-} /* on_write_chunk */
+    total_samples += wpdata->ckhdr.pcm_count;
 
-static bool on_start_file(struct enc_file_event_data *data)
-{
-    if ((data->chunk->flags & CHUNKF_ERROR) || *data->filename == '\0')
-        return false;
-
-    data->rec_file = ci->open(data->filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
-
-    if (data->rec_file < 0)
-        return false;
+    return 0;
+}
 
+static int on_stream_start(void)
+{
     /* reset sample count */
-    data->num_pcm_samples = 0;
+    total_samples = 0;
 
     /* write template headers */
-    if (ci->write(data->rec_file, &wvpk_mdh, sizeof (wvpk_mdh))
-            != sizeof (wvpk_mdh) ||
-        ci->write(data->rec_file, &riff_header, sizeof (riff_header))
-            != sizeof (riff_header))
-    {
-        return false;
-    }
+    if (ci->enc_stream_write(&wvpk_mdh, sizeof (wvpk_mdh))
+            != sizeof (wvpk_mdh))
+        return -1;
+
+    if (ci->enc_stream_write(&riff_template_header,
+                             sizeof (riff_template_header))
+            != sizeof (riff_template_header))
+        return -2;
 
-    data->new_enc_size += sizeof(wvpk_mdh) + sizeof(riff_header);
-    return true;
-} /* on_start_file */
+    return 0;
+}
 
-static bool on_end_file(struct enc_file_event_data *data)
+static int on_stream_end(void)
 {
     struct
     {
@@ -255,19 +184,16 @@ static bool on_end_file(struct enc_file_event_data *data)
         WavpackHeader         wph;
     } __attribute__ ((packed)) h;
 
-    uint32_t data_size;
-
-    if (data->rec_file < 0)
-        return false; /* file already closed, nothing more we can do */
-
-    /* always _try_ to write the file header, even on error */
+    /* Correcting sizes on error is a bit of a pain */
 
     /* read template headers at start */
-    if (ci->lseek(data->rec_file, 0, SEEK_SET) != 0 ||
-        ci->read(data->rec_file, &h, sizeof (h)) != sizeof (h))
-        return false;
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0)
+        return -1;
 
-    data_size = data->num_pcm_samples*config.num_channels*PCM_DEPTH_BYTES;
+    if (ci->enc_stream_read(&h, sizeof (h)) != sizeof (h))
+        return -2;
+
+    size_t data_size = total_samples*config.num_channels*PCM_DEPTH_BYTES;
 
     /** "RIFF" header **/
     h.rhdr.riff_size    = htole32(RIFF_FMT_HEADER_SIZE +
@@ -286,121 +212,29 @@ static bool on_end_file(struct enc_file_event_data *data)
     /** Wavpack header **/
     h.wph.ckSize        = htole32(letoh32(h.wph.ckSize) + sizeof (h.wpmdh)
                                 + sizeof (h.rhdr));
-    h.wph.total_samples = htole32(data->num_pcm_samples);
+    h.wph.total_samples = htole32(total_samples);
 
     /* MDH|RIFF|WVPK => WVPK|MDH|RIFF */
-    if (ci->lseek(data->rec_file, 0, SEEK_SET)
-            != 0 ||
-        ci->write(data->rec_file, &h.wph, sizeof (h.wph))
-            != sizeof (h.wph) ||
-        ci->write(data->rec_file, &h.wpmdh, sizeof (h.wpmdh))
-            != sizeof (h.wpmdh) ||
-        ci->write(data->rec_file, &h.rhdr, sizeof (h.rhdr))
-            != sizeof (h.rhdr) ||
-        ci->close(data->rec_file) != 0 )
-    {
-        return false;
-    }
-
-    data->rec_file = -1;
-
-    return true;
-} /* on_end_file */
+    if (ci->enc_stream_lseek(0, SEEK_SET) != 0)
+        return -3;
 
-static void enc_events_callback(enum enc_events event, void *data)
-                                    ICODE_ATTR;
-static void enc_events_callback(enum enc_events event, void *data)
-{
-    switch (event)
-    {
-    case ENC_WRITE_CHUNK:
-        if (on_write_chunk((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_START_FILE:
-        /* write metadata header and RIFF header */
-        if (on_start_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    case ENC_END_FILE:
-        if (on_end_file((struct enc_file_event_data *)data))
-            return;
-
-        break;
-
-    default:
-        return;
-    }
-
-    /* Something failed above. Signal error back to core. */
-    ((struct enc_file_event_data *)data)->chunk->flags |= CHUNKF_ERROR;
-} /* enc_events_callback */
-
-static bool init_encoder(void)
-{
-    struct enc_inputs     inputs;
-    struct enc_parameters params;
-
-    codec_init();
-
-    if (ci->enc_get_inputs         == NULL ||
-        ci->enc_set_parameters     == NULL ||
-        ci->enc_get_chunk          == NULL ||
-        ci->enc_finish_chunk       == NULL ||
-        ci->enc_get_pcm_data       == NULL ||
-        ci->enc_unget_pcm_data     == NULL )
-        return false;
-
-    ci->enc_get_inputs(&inputs);
-
-    if (inputs.config->afmt != AFMT_WAVPACK)
-        return false;
-
-    memset(&config, 0, sizeof (config));
-    config.bits_per_sample  = PCM_DEPTH_BITS;
-    config.bytes_per_sample = PCM_DEPTH_BYTES;
-    config.sample_rate      = inputs.sample_rate;
-    config.num_channels     = inputs.num_channels;
+    if (ci->enc_stream_write(&h.wph, sizeof (h.wph)) != sizeof (h.wph))
+        return -4;
 
-    wpc = WavpackOpenFileOutput ();
+    if (ci->enc_stream_write(&h.wpmdh, sizeof (h.wpmdh)) != sizeof (h.wpmdh))
+        return -5;
 
-    if (!WavpackSetConfiguration(wpc, &config, -1))
-        return false;
+    if (ci->enc_stream_write(&h.rhdr, sizeof (h.rhdr)) != sizeof (h.rhdr))
+        return -6;
 
-    err = 0;
-
-    /* configure the buffer system */
-    params.afmt            = AFMT_WAVPACK;
-    input_size             = PCM_CHUNK_SIZE*inputs.num_channels / 2;
-    data_size              = 105*input_size / 100;
-    input_size            *= 2;
-    input_step             = input_size / 4;
-    params.chunk_size      = data_size;
-    params.enc_sample_rate = inputs.sample_rate;
-    params.reserve_bytes   = 0;
-    params.events_callback = enc_events_callback;
-
-    ci->enc_set_parameters(&params);
-
-    return true;
-} /* init_encoder */
+    return 0;
+}
 
 /* this is the codec entry point */
 enum codec_status codec_main(enum codec_entry_call_reason reason)
 {
-    if (reason == CODEC_LOAD) {
-        /* initialize params and config */
-        if (!init_encoder())
-            return CODEC_ERROR;
-    }
-    else if (reason == CODEC_UNLOAD) {
-        /* reset parameters to initial state */
-        ci->enc_set_parameters(NULL);
-    }
+    if (reason == CODEC_LOAD)
+        codec_init();
 
     return CODEC_OK;
 }
@@ -408,60 +242,89 @@ enum codec_status codec_main(enum codec_entry_call_reason reason)
 /* this is called for each file to process */
 enum codec_status codec_run(void)
 {
+    enum { GETBUF_ENC, GETBUF_PCM } getbuf = GETBUF_ENC;
+    struct enc_chunk_data *data = NULL;
+
     /* main encoding loop */
-    while(ci->get_command(NULL) != CODEC_ACTION_HALT)
+    while (1)
     {
-        uint8_t *src = (uint8_t *)ci->enc_get_pcm_data(PCM_CHUNK_SIZE);
-        struct enc_chunk_hdr *chunk;
-        bool abort_chunk;
-        uint8_t *dst;
-        uint8_t *src_end;
-
-        if(src == NULL)
-            continue;
-
-        chunk = ci->enc_get_chunk();
-
-        /* reset counts and pointer */
-        chunk->enc_size = 0;
-        chunk->num_pcm  = 0;
-        chunk->enc_data = NULL;
-
-        dst = ENC_CHUNK_SKIP_HDR(dst, chunk);
+        enum codec_command_action action = ci->get_command(NULL);
 
-        WavpackStartBlock(wpc, dst, dst + data_size);
+        if (action != CODEC_ACTION_NULL)
+            break;
 
-        chunk_to_int32((uint32_t*)src);
-        src      = input_buffer;
-        src_end  = src + input_size;
-
-        /* encode chunk in four steps yielding between each */
-        do
+        /* First obtain output buffer; when available, get PCM data */
+        switch (getbuf)
         {
-            abort_chunk = true;
-            if (WavpackPackSamples(wpc, (int32_t *)src,
-                                   PCM_SAMP_PER_CHUNK/4))
-            {
-                chunk->num_pcm += PCM_SAMP_PER_CHUNK/4;
-                ci->yield();
-                /* could've been stopped in some way */
-                abort_chunk = chunk->flags & CHUNKF_ABORT;
-            }
-
-            src += input_step;
+        case GETBUF_ENC:
+            if (!(data = ci->enc_encbuf_get_buffer(out_reqsize)))
+                continue;
+            getbuf = GETBUF_PCM;
+        case GETBUF_PCM:
+            if (!ci->enc_pcmbuf_read(input_buffer + PCM_SAMP_PER_CHUNK,
+                                     PCM_SAMP_PER_CHUNK))
+                continue;
+            getbuf = GETBUF_ENC;
         }
-        while (!abort_chunk && src < src_end);
 
-        if (!abort_chunk)
+        input_buffer_to_int32(frame_size);
+
+        if (WavpackStartBlock(wpc, data->data, data->data + out_reqsize) &&
+            WavpackPackSamples(wpc, input_buffer, PCM_SAMP_PER_CHUNK))
         {
-            chunk->enc_data = dst;
-            if (chunk->num_pcm < PCM_SAMP_PER_CHUNK)
-                ci->enc_unget_pcm_data(PCM_CHUNK_SIZE - chunk->num_pcm*4);
             /* finish the chunk and store chunk size info */
-            chunk->enc_size = WavpackFinishBlock(wpc);
-            ci->enc_finish_chunk();
+            data->hdr.size = WavpackFinishBlock(wpc);
+            data->pcm_count = PCM_SAMP_PER_CHUNK;
         }
+        else
+        {
+            data->hdr.err = 1;
+        }
+
+        ci->enc_pcmbuf_advance(PCM_SAMP_PER_CHUNK);
+        ci->enc_encbuf_finish_buffer();
     }
 
     return CODEC_OK;
 }
+
+/* this is called by recording system */
+int ICODE_ATTR enc_callback(enum enc_callback_reason reason,
+                            void *params)
+{
+    if (LIKELY(reason == ENC_CB_STREAM))
+    {
+        switch (((union enc_chunk_hdr *)params)->type)
+        {
+        case CHUNK_T_DATA:
+            return on_stream_data(params);
+        case CHUNK_T_STREAM_START:
+            return on_stream_start();
+        case CHUNK_T_STREAM_END:
+            return on_stream_end();
+        }
+    }
+    else if (reason == ENC_CB_INPUTS)
+    {
+        /* Save parameters */
+        struct enc_inputs *inputs = params;
+        sample_rate = inputs->sample_rate;
+        num_channels = inputs->num_channels;
+        frame_size = PCM_SAMP_PER_CHUNK*PCM_DEPTH_BYTES*num_channels;
+        out_reqsize = frame_size*110 / 100; /* Add 10% */
+
+        /* Setup Wavpack encoder */
+        memset(&config, 0, sizeof (config));
+        config.bits_per_sample = PCM_DEPTH_BITS;
+        config.bytes_per_sample = PCM_DEPTH_BYTES;
+        config.sample_rate = sample_rate;
+        config.num_channels = num_channels;
+
+        wpc = WavpackOpenFileOutput();
+
+        if (!WavpackSetConfiguration(wpc, &config, -1))
+            return -1;
+    }
+
+    return 0;
+}