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Diffstat (limited to 'apps/plugins/mpegplayer/mpeg_parser.c')
-rw-r--r--apps/plugins/mpegplayer/mpeg_parser.c1203
1 files changed, 1203 insertions, 0 deletions
diff --git a/apps/plugins/mpegplayer/mpeg_parser.c b/apps/plugins/mpegplayer/mpeg_parser.c
new file mode 100644
index 0000000000..cc57b0c43c
--- /dev/null
+++ b/apps/plugins/mpegplayer/mpeg_parser.c
@@ -0,0 +1,1203 @@
+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Parser for MPEG streams
+ *
+ * Copyright (c) 2007 Michael Sevakis
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "plugin.h"
+#include "mpegplayer.h"
+
+struct stream_parser str_parser SHAREDBSS_ATTR;
+
+static void parser_init_state(void)
+{
+ str_parser.last_seek_time = 0;
+ str_parser.format = STREAM_FMT_UNKNOWN;
+ str_parser.start_pts = INVALID_TIMESTAMP;
+ str_parser.end_pts = INVALID_TIMESTAMP;
+ str_parser.flags = 0;
+ str_parser.dims.w = 0;
+ str_parser.dims.h = 0;
+}
+
+/* Place the stream in a state to begin parsing - sync will be performed
+ * first */
+void str_initialize(struct stream *str, off_t pos)
+{
+ /* Initial positions start here */
+ str->hdr.win_left = str->hdr.win_right = pos;
+ /* No packet */
+ str->curr_packet = NULL;
+ /* Pick up parsing from this point in the buffer */
+ str->curr_packet_end = disk_buf_offset2ptr(pos);
+ /* No flags */
+ str->pkt_flags = 0;
+ /* Sync first */
+ str->state = SSTATE_SYNC;
+}
+
+/* Place the stream in an end of data state */
+void str_end_of_stream(struct stream *str)
+{
+ /* Offsets that prevent this stream from being included in the
+ * min left/max right window so that no buffering is triggered on
+ * its behalf. Set right to the min first so a thread reading the
+ * overall window gets doesn't see this as valid no matter what the
+ * file length. */
+ str->hdr.win_right = OFF_T_MIN;
+ str->hdr.win_left = OFF_T_MAX;
+ /* No packets */
+ str->curr_packet = str->curr_packet_end = NULL;
+ /* No flags */
+ str->pkt_flags = 0;
+ /* Fin */
+ str->state = SSTATE_END;
+}
+
+/* Return a timestamp at address p+offset if the marker bits are in tact */
+static inline uint32_t read_pts(uint8_t *p, off_t offset)
+{
+ return TS_CHECK_MARKERS(p, offset) ?
+ TS_FROM_HEADER(p, offset) : INVALID_TIMESTAMP;
+}
+
+static inline bool validate_timestamp(uint32_t ts)
+{
+ return ts >= str_parser.start_pts && ts <= str_parser.end_pts;
+}
+
+/* Find a start code before or after a given position */
+uint8_t * mpeg_parser_scan_start_code(struct stream_scan *sk, uint32_t code)
+{
+ stream_scan_normalize(sk);
+
+ if (sk->dir < 0)
+ {
+ /* Reverse scan - start with at least the min needed */
+ stream_scan_offset(sk, 4);
+ }
+
+ code &= 0xff; /* Only the low byte matters */
+
+ while (sk->len >= 0 && sk->margin >= 4)
+ {
+ uint8_t *p;
+ off_t pos = disk_buf_lseek(sk->pos, SEEK_SET);
+ ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 4, &p);
+
+ if (pos < 0 || len < 4)
+ break;
+
+ if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX) && p[3] == code)
+ {
+ return p;
+ }
+
+ stream_scan_offset(sk, 1);
+ }
+
+ return NULL;
+}
+
+/* Find a PES packet header for any stream - return stream to which it
+ * belongs */
+unsigned mpeg_parser_scan_pes(struct stream_scan *sk)
+{
+ stream_scan_normalize(sk);
+
+ if (sk->dir < 0)
+ {
+ /* Reverse scan - start with at least the min needed */
+ stream_scan_offset(sk, 4);
+ }
+
+ while (sk->len >= 0 && sk->margin >= 4)
+ {
+ uint8_t *p;
+ off_t pos = disk_buf_lseek(sk->pos, SEEK_SET);
+ ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 4, &p);
+
+ if (pos < 0 || len < 4)
+ break;
+
+ if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX))
+ {
+ unsigned id = p[3];
+ if (id >= 0xb9)
+ return id; /* PES header */
+ /* else some video stream element */
+ }
+
+ stream_scan_offset(sk, 1);
+ }
+
+ return -1;
+}
+
+/* Return the first SCR found from the scan direction */
+uint32_t mpeg_parser_scan_scr(struct stream_scan *sk)
+{
+ uint8_t *p = mpeg_parser_scan_start_code(sk, MPEG_STREAM_PACK_HEADER);
+
+ if (p != NULL && sk->margin >= 9) /* 9 bytes total required */
+ {
+ sk->data = 9;
+
+ if ((p[4] & 0xc0) == 0x40) /* mpeg-2 */
+ {
+ /* Lookhead p+8 */
+ if (MPEG2_CHECK_PACK_SCR_MARKERS(p, 4))
+ return MPEG2_PACK_HEADER_SCR(p, 4);
+ }
+ else if ((p[4] & 0xf0) == 0x20) /* mpeg-1 */
+ {
+ /* Lookahead p+8 */
+ if (TS_CHECK_MARKERS(p, 4))
+ return TS_FROM_HEADER(p, 4);
+ }
+ /* Weird pack header */
+ sk->data = 5;
+ }
+
+ return INVALID_TIMESTAMP;
+}
+
+uint32_t mpeg_parser_scan_pts(struct stream_scan *sk, unsigned id)
+{
+ stream_scan_normalize(sk);
+
+ if (sk->dir < 0)
+ {
+ /* Reverse scan - start with at least the min needed */
+ stream_scan_offset(sk, 4);
+ }
+
+ while (sk->len >= 0 && sk->margin >= 4)
+ {
+ uint8_t *p;
+ off_t pos = disk_buf_lseek(sk->pos, SEEK_SET);
+ ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 30, &p);
+
+ if (pos < 0 || len < 4)
+ break;
+
+ if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX) && p[3] == id)
+ {
+ uint8_t *h = p;
+
+ if (sk->margin < 7)
+ {
+ /* Insufficient data */
+ }
+ else if ((h[6] & 0xc0) == 0x80) /* mpeg2 */
+ {
+ if (sk->margin >= 14 && (h[7] & 0x80) != 0x00)
+ {
+ sk->data = 14;
+ return read_pts(h, 9);
+ }
+ }
+ else /* mpeg1 */
+ {
+ ssize_t l = 6;
+ ssize_t margin = sk->margin;
+
+ /* Skip stuffing_byte */
+ while (margin > 7 && h[l] == 0xff && ++l <= 22)
+ --margin;
+
+ if (margin >= 7)
+ {
+ if ((h[l] & 0xc0) == 0x40)
+ {
+ /* Skip STD_buffer_scale and STD_buffer_size */
+ margin -= 2;
+ l += 2;
+ }
+
+ if (margin >= 5)
+ {
+ /* Header points to the mpeg1 pes header */
+ h += l;
+
+ if ((h[0] & 0xe0) == 0x20)
+ {
+ /* PTS or PTS_DTS indicated */
+ sk->data = (h + 5) - p;
+ return read_pts(h, 0);
+ }
+ }
+ }
+ }
+ /* No PTS present - keep searching for a matching PES header with
+ * one */
+ }
+
+ stream_scan_offset(sk, 1);
+ }
+
+ return INVALID_TIMESTAMP;
+}
+
+static bool init_video_info(void)
+{
+ DEBUGF("Getting movie size\n");
+
+ /* The decoder handles this in order to initialize its knowledge of the
+ * movie parameters making seeking easier */
+ str_send_msg(&video_str, STREAM_RESET, 0);
+ if (str_send_msg(&video_str, VIDEO_GET_SIZE,
+ (intptr_t)&str_parser.dims) != 0)
+ {
+ return true;
+ }
+
+ DEBUGF(" failed\n");
+ return false;
+}
+
+static bool init_times(struct stream *str)
+{
+ struct stream tmp_str;
+ const ssize_t filesize = disk_buf_filesize();
+ const ssize_t max_probe = MIN(512*1024, filesize);
+ bool found_stream;
+
+ /* Simply find the first earliest timestamp - this will be the one
+ * used when streaming anyway */
+ DEBUGF("Finding start_pts: 0x%02x\n", str->id);
+
+ found_stream = false;
+ str->start_pts = INVALID_TIMESTAMP;
+ str->end_pts = INVALID_TIMESTAMP;
+
+ tmp_str.id = str->id;
+ tmp_str.hdr.pos = 0;
+ tmp_str.hdr.limit = max_probe;
+
+ /* Probe for many for the start because some stamps could be anomalous.
+ * Video also can also have things out of order. Just see what it's got.
+ */
+ while (1)
+ {
+ switch (parser_get_next_data(&tmp_str, STREAM_PM_RANDOM_ACCESS))
+ {
+ case STREAM_DATA_END:
+ break;
+ case STREAM_OK:
+ found_stream = true;
+ if (tmp_str.pkt_flags & PKT_HAS_TS)
+ {
+ if (tmp_str.pts < str->start_pts)
+ str->start_pts = tmp_str.pts;
+ }
+ continue;
+ }
+
+ break;
+ }
+
+ if (!found_stream)
+ {
+ DEBUGF(" stream not found:0x%02x\n", str->id);
+ return false;
+ }
+
+ DEBUGF(" start:%u\n", (unsigned)str->start_pts);
+
+ /* Use the decoder thread to perform a synchronized search - no
+ * decoding should take place but just a simple run through timestamps
+ * and durations as the decoder would see them. This should give the
+ * precise time at the end of the last frame for the stream. */
+ DEBUGF("Finding end_pts: 0x%02x\n", str->id);
+
+ str_parser.parms.sd.time = MAX_TIMESTAMP;
+ str_parser.parms.sd.sk.pos = filesize - max_probe;
+ str_parser.parms.sd.sk.len = max_probe;
+ str_parser.parms.sd.sk.dir = SSCAN_FORWARD;
+
+ str_send_msg(str, STREAM_RESET, 0);
+
+ if (str_send_msg(str, STREAM_FIND_END_TIME,
+ (intptr_t)&str_parser.parms.sd) == STREAM_PERFECT_MATCH)
+ {
+ str->end_pts = str_parser.parms.sd.time;
+ DEBUGF(" end:%u\n", (unsigned)str->end_pts);
+ }
+
+ return true;
+}
+
+static bool check_times(const struct stream *str)
+{
+ return str->start_pts < str->end_pts &&
+ str->end_pts != INVALID_TIMESTAMP;
+}
+
+/* Return the best-fit file offset of a timestamp in the PES where
+ * timstamp <= time < next timestamp. Will try to return something reasonably
+ * valid if best-fit could not be made. */
+static off_t mpeg_parser_seek_PTS(uint32_t time, unsigned id)
+{
+ ssize_t pos_left = 0;
+ ssize_t pos_right = disk_buf.filesize;
+ ssize_t pos, pos_new;
+ uint32_t time_left = str_parser.start_pts;
+ uint32_t time_right = str_parser.end_pts;
+ uint32_t pts = 0;
+ uint32_t prevpts = 0;
+ enum state_enum state = STATE0;
+ struct stream_scan sk;
+
+ stream_scan_init(&sk);
+
+ /* Initial estimate taken from average bitrate - later interpolations are
+ * taken similarly based on the remaining file interval */
+ pos_new = muldiv_uint32(time - time_left, pos_right - pos_left,
+ time_right - time_left) + pos_left;
+
+ /* return this estimated position if nothing better comes up */
+ pos = pos_new;
+
+ DEBUGF("Seeking stream 0x%02x\n", id);
+ DEBUGF("$$ tl:%u t:%u ct:?? tr:%u\n pl:%ld pn:%ld pr:%ld\n",
+ (unsigned)time_left, (unsigned)time, (unsigned)time_right,
+ (long)pos_left, (long)pos_new, (long)pos_right);
+
+ sk.dir = SSCAN_REVERSE;
+
+ while (state < STATE9)
+ {
+ uint32_t currpts;
+ sk.pos = pos_new;
+ sk.len = (sk.dir < 0) ? pos_new - pos_left : pos_right - pos_new;
+
+ currpts = mpeg_parser_scan_pts(&sk, id);
+
+ if (currpts != INVALID_TIMESTAMP)
+ {
+ ssize_t pos_adj; /* Adjustment to over or under-estimate */
+
+ /* Found a valid timestamp - see were it lies in relation to
+ * target */
+ if (currpts < time)
+ {
+ /* Time at current position is before seek time - move
+ * forward */
+ if (currpts > pts)
+ {
+ /* This is less than the desired time but greater than
+ * the currently seeked one; move the position up */
+ pts = currpts;
+ pos = sk.pos;
+ }
+
+ /* No next timestamp can be sooner */
+ pos_left = sk.pos + sk.data;
+ time_left = currpts;
+
+ if (pos_right <= pos_left)
+ break; /* If the window disappeared - we're done */
+
+ pos_new = muldiv_uint32(time - time_left,
+ pos_right - pos_left,
+ time_right - time_left);
+ /* Point is ahead of us - fudge estimate a bit high */
+ pos_adj = pos_new / 10;
+
+ if (pos_adj > 512*1024)
+ pos_adj = 512*1024;
+
+ pos_new += pos_left + pos_adj;
+
+ if (pos_new >= pos_right)
+ {
+ /* Estimate could push too far */
+ pos_new = pos_right;
+ }
+
+ state = STATE2; /* Last scan was early */
+ sk.dir = SSCAN_REVERSE;
+
+ DEBUGF(">> tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n",
+ (unsigned)time_left, (unsigned)time, (unsigned)currpts,
+ (unsigned)time_right, (long)pos_left, (long)pos_new,
+ (long)pos_right);
+ }
+ else if (currpts > time)
+ {
+ /* Time at current position is past seek time - move
+ backward */
+ pos_right = sk.pos;
+ time_right = currpts;
+
+ if (pos_right <= pos_left)
+ break; /* If the window disappeared - we're done */
+
+ pos_new = muldiv_uint32(time - time_left,
+ pos_right - pos_left,
+ time_right - time_left);
+ /* Overshot the seek point - fudge estimate a bit low */
+ pos_adj = pos_new / 10;
+
+ if (pos_adj > 512*1024)
+ pos_adj = 512*1024;
+
+ pos_new += pos_left - pos_adj;
+
+ state = STATE3; /* Last scan was late */
+ sk.dir = SSCAN_REVERSE;
+
+ DEBUGF("<< tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n",
+ (unsigned)time_left, (unsigned)time, (unsigned)currpts,
+ (unsigned)time_right, (long)pos_left, (long)pos_new,
+ (long)pos_right);
+ }
+ else
+ {
+ /* Exact match - it happens */
+ DEBUGF("|| tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n",
+ (unsigned)time_left, (unsigned)time, (unsigned)currpts,
+ (unsigned)time_right, (long)pos_left, (long)pos_new,
+ (long)pos_right);
+ pts = currpts;
+ pos = sk.pos;
+ state = STATE9;
+ }
+ }
+ else
+ {
+ /* Nothing found */
+
+ switch (state)
+ {
+ case STATE1:
+ /* We already tried the bruteforce scan and failed again - no
+ * more stamps could possibly exist in the interval */
+ DEBUGF("!! no timestamp 2x\n");
+ break;
+ case STATE0:
+ /* Hardly likely except at very beginning - just do L->R scan
+ * to find something */
+ DEBUGF("!! no timestamp on first probe: %ld\n", sk.pos);
+ case STATE2:
+ case STATE3:
+ /* Could just be missing timestamps because the interval is
+ * narrowing down. A large block of data from another stream
+ * may also be in the midst of our chosen points which could
+ * cluster at either extreme end. If anything is there, this
+ * will find it. */
+ pos_new = pos_left;
+ sk.dir = SSCAN_FORWARD;
+ DEBUGF("?? tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n",
+ (unsigned)time_left, (unsigned)time, (unsigned)currpts,
+ (unsigned)time_right, (long)pos_left, (long)pos_new,
+ (long)pos_right);
+ state = STATE1;
+ break;
+ default:
+ DEBUGF("?? Invalid state: %d\n", state);
+ }
+ }
+
+ /* Same timestamp twice = quit */
+ if (currpts == prevpts)
+ {
+ DEBUGF("!! currpts == prevpts (stop)\n");
+ state = STATE9;
+ }
+
+ prevpts = currpts;
+ }
+
+#if defined(DEBUG) || defined(SIMULATOR)
+ /* The next pts after the seeked-to position should be greater -
+ * most of the time - frames out of presentation order may muck it
+ * up a slight bit */
+ sk.pos = pos + 1;
+ sk.len = disk_buf.filesize;
+ sk.dir = SSCAN_FORWARD;
+
+ uint32_t nextpts = mpeg_parser_scan_pts(&sk, id);
+ DEBUGF("Seek pos:%ld pts:%u t:%u next pts:%u \n",
+ (long)pos, (unsigned)pts, (unsigned)time, (unsigned)nextpts);
+
+ if (pts <= time && time < nextpts)
+ {
+ /* Smile - it worked */
+ DEBUGF(" :) pts<=time<next pts\n");
+ }
+ else
+ {
+ /* See where things ended up */
+ if (pts > time)
+ {
+ /* Hmm */
+ DEBUGF(" :\\ pts>time\n");
+ }
+ if (pts >= nextpts)
+ {
+ /* Weird - probably because of encoded order & tends to be right
+ * anyway if other criteria are met */
+ DEBUGF(" :p pts>=next pts\n");
+ }
+ if (time >= nextpts)
+ {
+ /* Ugh */
+ DEBUGF(" :( time>=nextpts\n");
+ }
+ }
+#endif
+
+ return pos;
+}
+
+static void prepare_audio(uint32_t time)
+{
+ off_t pos;
+
+ if (!str_send_msg(&audio_str, STREAM_NEEDS_SYNC, time))
+ {
+ DEBUGF("Audio was ready\n");
+ return;
+ }
+
+ pos = mpeg_parser_seek_PTS(time, audio_str.id);
+ str_send_msg(&audio_str, STREAM_RESET, 0);
+
+ str_parser.parms.sd.time = time;
+ str_parser.parms.sd.sk.pos = pos;
+ str_parser.parms.sd.sk.len = 1024*1024;
+ str_parser.parms.sd.sk.dir = SSCAN_FORWARD;
+
+ str_send_msg(&audio_str, STREAM_SYNC, (intptr_t)&str_parser.parms.sd);
+}
+
+/* This function demuxes the streams and gives the next stream data
+ * pointer.
+ *
+ * STREAM_PM_STREAMING is for operation during playback. If the nescessary
+ * data and worst-case lookahead margin is not available, the stream is
+ * registered for notification when the data becomes available. If parsing
+ * extends beyond the end of the file or the end of stream marker is reached,
+ * STREAM_DATA_END is returned and the stream state changed to SSTATE_EOS.
+ *
+ * STREAM_PM_RANDOM_ACCESS is for operation when not playing such as seeking.
+ * If the file cache misses for the current position + lookahead, it will be
+ * loaded from disk. When the specified limit is reached, STREAM_DATA_END is
+ * returned.
+ *
+ * The results from one mode may be used as input to the other. Random access
+ * requires cooperation amongst threads to avoid evicting another stream's
+ * data.
+ */
+static int parse_demux(struct stream *str, enum stream_parse_mode type)
+{
+ #define INC_BUF(offset) \
+ ({ off_t _o = (offset); \
+ str->hdr.win_right += _o; \
+ if ((p += _o) >= disk_buf.end) \
+ p -= disk_buf.size; })
+
+ static const int mpeg1_skip_table[16] =
+ { 0, 0, 4, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+
+ uint8_t *p = str->curr_packet_end;
+
+ str->pkt_flags = 0;
+
+ while (1)
+ {
+ uint8_t *header;
+ unsigned id;
+ ssize_t length, bytes;
+
+ switch (type)
+ {
+ case STREAM_PM_STREAMING:
+ /* Has the end been reached already? */
+ switch (str->state)
+ {
+ case SSTATE_PARSE: /* Expected case first if no jumptable */
+ /* Are we at the end of file? */
+ if (str->hdr.win_left < disk_buf.filesize)
+ break;
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+
+ case SSTATE_SYNC:
+ /* Is sync at the end of file? */
+ if (str->hdr.win_right < disk_buf.filesize)
+ break;
+ str_end_of_stream(str);
+ /* Fall-through */
+ case SSTATE_END:
+ return STREAM_DATA_END;
+ }
+
+ if (!disk_buf_is_data_ready(&str->hdr, MIN_BUFAHEAD))
+ {
+ /* This data range is not buffered yet - register stream to
+ * be notified when it becomes available. Stream is obliged
+ * to enter a TSTATE_DATA state if it must wait. */
+ int res = str_next_data_not_ready(str);
+
+ if (res != STREAM_OK)
+ return res;
+ }
+ break;
+ /* STREAM_PM_STREAMING: */
+
+ case STREAM_PM_RANDOM_ACCESS:
+ str->hdr.pos = disk_buf_lseek(str->hdr.pos, SEEK_SET);
+
+ if (str->hdr.pos < 0 || str->hdr.pos >= str->hdr.limit ||
+ disk_buf_getbuffer(MIN_BUFAHEAD, &p, NULL, NULL) <= 0)
+ {
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+ }
+
+ str->state = SSTATE_SYNC;
+ str->hdr.win_left = str->hdr.pos;
+ str->curr_packet = NULL;
+ str->curr_packet_end = p;
+ break;
+ /* STREAM_PM_RANDOM_ACCESS: */
+ }
+
+ if (str->state == SSTATE_SYNC)
+ {
+ /* Scanning for start code */
+ if (!CMP_3_CONST(p, PACKET_START_CODE_PREFIX))
+ {
+ INC_BUF(1);
+ continue;
+ }
+ }
+
+ /* Found a start code - enter parse state */
+ str->state = SSTATE_PARSE;
+
+ /* Pack header, skip it */
+ if (CMP_4_CONST(p, PACK_START_CODE))
+ {
+ /* Max lookahead: 14 */
+ if ((p[4] & 0xc0) == 0x40) /* mpeg-2 */
+ {
+ /* Max delta: 14 + 7 = 21 */
+ /* Skip pack header and any stuffing bytes*/
+ bytes = 14 + (p[13] & 7);
+ }
+ else if ((p[4] & 0xf0) == 0x20) /* mpeg-1 */
+ {
+ bytes = 12;
+ }
+ else /* unknown - skip it */
+ {
+ DEBUGF("weird pack header!\n");
+ bytes = 5;
+ }
+
+ INC_BUF(bytes);
+ }
+
+ /* System header, parse and skip it - 6 bytes + size */
+ if (CMP_4_CONST(p, SYSTEM_HEADER_START_CODE))
+ {
+ /* Skip start code */
+ /* Max Delta = 65535 + 6 = 65541 */
+ bytes = 6 + ((p[4] << 8) | p[5]);
+ INC_BUF(bytes);
+ }
+
+ /* Packet header, parse it */
+ if (!CMP_3_CONST(p, PACKET_START_CODE_PREFIX))
+ {
+ /* Problem? Meh...probably not but just a corrupted section.
+ * Try to resync the parser which will probably succeed. */
+ DEBUGF("packet start code prefix not found: 0x%02x\n"
+ " wl:%lu wr:%lu\n"
+ " p:%p cp:%p cpe:%p\n"
+ " dbs:%p dbe:%p dbt:%p\n",
+ str->id, str->hdr.win_left, str->hdr.win_right,
+ p, str->curr_packet, str->curr_packet_end,
+ disk_buf.start, disk_buf.end, disk_buf.tail);
+ str->state = SSTATE_SYNC;
+ INC_BUF(1); /* Next byte - this one's no good */
+ continue;
+ }
+
+ /* We retrieve basic infos */
+ /* Maximum packet length: 6 + 65535 = 65541 */
+ id = p[3];
+ length = ((p[4] << 8) | p[5]) + 6;
+
+ if (id != str->id)
+ {
+ switch (id)
+ {
+ case MPEG_STREAM_PROGRAM_END:
+ /* end of stream */
+ str_end_of_stream(str);
+ DEBUGF("MPEG program end: 0x%02x\n", str->id);
+ return STREAM_DATA_END;
+ case MPEG_STREAM_PACK_HEADER:
+ case MPEG_STREAM_SYSTEM_HEADER:
+ /* These shouldn't be here - no increment or resync
+ * since we'll pick it up above. */
+ continue;
+ default:
+ /* It's not the packet we're looking for, skip it */
+ INC_BUF(length);
+ continue;
+ }
+ }
+
+ /* Ok, it's our packet */
+ header = p;
+
+ if ((header[6] & 0xc0) == 0x80) /* mpeg2 */
+ {
+ /* Max Lookahead: 18 */
+ /* Min length: 9 */
+ /* Max length: 9 + 255 = 264 */
+ length = 9 + header[8];
+
+ /* header points to the mpeg2 pes header */
+ if ((header[7] & 0x80) != 0)
+ {
+ /* header has a pts */
+ uint32_t pts = read_pts(header, 9);
+
+ if (pts != INVALID_TIMESTAMP)
+ {
+ str->pts = pts;
+#if 0
+ /* DTS isn't used for anything since things just get
+ decoded ASAP but keep the code around */
+ if (STREAM_IS_VIDEO(id))
+ {
+ /* Video stream - header may have a dts as well */
+ str->dts = pts;
+
+ if (header[7] & 0x40) != 0x00)
+ {
+ pts = read_pts(header, 14);
+ if (pts != INVALID_TIMESTAMP)
+ str->dts = pts;
+ }
+ }
+#endif
+ str->pkt_flags |= PKT_HAS_TS;
+ }
+ }
+ }
+ else /* mpeg1 */
+ {
+ /* Max lookahead: 24 + 2 + 9 = 35 */
+ /* Max len_skip: 24 + 2 = 26 */
+ /* Min length: 7 */
+ /* Max length: 24 + 2 + 9 = 35 */
+ off_t len_skip;
+ uint8_t * ptsbuf;
+
+ length = 7;
+
+ while (header[length - 1] == 0xff)
+ {
+ if (++length > 23)
+ {
+ DEBUGF("Too much stuffing" );
+ break;
+ }
+ }
+
+ if ((header[length - 1] & 0xc0) == 0x40)
+ length += 2;
+
+ len_skip = length;
+ length += mpeg1_skip_table[header[length - 1] >> 4];
+
+ /* Header points to the mpeg1 pes header */
+ ptsbuf = header + len_skip;
+
+ if ((ptsbuf[-1] & 0xe0) == 0x20 && TS_CHECK_MARKERS(ptsbuf, -1))
+ {
+ /* header has a pts */
+ uint32_t pts = read_pts(ptsbuf, -1);
+
+ if (pts != INVALID_TIMESTAMP)
+ {
+ str->pts = pts;
+#if 0
+ /* DTS isn't used for anything since things just get
+ decoded ASAP but keep the code around */
+ if (STREAM_IS_VIDEO(id))
+ {
+ /* Video stream - header may have a dts as well */
+ str->dts = pts;
+
+ if (ptsbuf[-1] & 0xf0) == 0x30)
+ {
+ pts = read_pts(ptsbuf, 4);
+
+ if (pts != INVALID_TIMESTAMP)
+ str->dts = pts;
+ }
+ }
+#endif
+ str->pkt_flags |= PKT_HAS_TS;
+ }
+ }
+ }
+
+ p += length;
+ /* Max bytes: 6 + 65535 - 7 = 65534 */
+ bytes = 6 + (header[4] << 8) + header[5] - length;
+
+ str->curr_packet = p;
+ str->curr_packet_end = p + bytes;
+ str->hdr.win_left = str->hdr.win_right + length;
+ str->hdr.win_right = str->hdr.win_left + bytes;
+
+ if (str->hdr.win_right > disk_buf.filesize)
+ {
+ /* No packet that exceeds end of file can be valid */
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+ }
+
+ return STREAM_OK;
+ } /* end while */
+
+ #undef INC_BUF
+}
+
+/* This simply reads data from the file one page at a time and returns a
+ * pointer to it in the buffer. */
+static int parse_elementary(struct stream *str, enum stream_parse_mode type)
+{
+ uint8_t *p;
+ ssize_t len = 0;
+
+ str->pkt_flags = 0;
+
+ switch (type)
+ {
+ case STREAM_PM_STREAMING:
+ /* Has the end been reached already? */
+ if (str->state == SSTATE_END)
+ return STREAM_DATA_END;
+
+ /* Are we at the end of file? */
+ if (str->hdr.win_left >= disk_buf.filesize)
+ {
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+ }
+
+ if (!disk_buf_is_data_ready(&str->hdr, MIN_BUFAHEAD))
+ {
+ /* This data range is not buffered yet - register stream to
+ * be notified when it becomes available. Stream is obliged
+ * to enter a TSTATE_DATA state if it must wait. */
+ int res = str_next_data_not_ready(str);
+
+ if (res != STREAM_OK)
+ return res;
+ }
+
+ len = DISK_BUF_PAGE_SIZE;
+
+ if ((size_t)(str->hdr.win_right + len) > (size_t)disk_buf.filesize)
+ len = disk_buf.filesize - str->hdr.win_right;
+
+ if (len <= 0)
+ {
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+ }
+
+ p = str->curr_packet_end;
+ if (p >= disk_buf.end)
+ p -= disk_buf.size;
+ break;
+ /* STREAM_PM_STREAMING: */
+
+ case STREAM_PM_RANDOM_ACCESS:
+ str->hdr.pos = disk_buf_lseek(str->hdr.pos, SEEK_SET);
+ len = disk_buf_getbuffer(DISK_BUF_PAGE_SIZE, &p, NULL, NULL);
+
+ if (len <= 0 || str->hdr.pos < 0 || str->hdr.pos >= str->hdr.limit)
+ {
+ str_end_of_stream(str);
+ return STREAM_DATA_END;
+ }
+ break;
+ /* STREAM_PM_RANDOM_ACCESS: */
+ }
+
+ str->state = SSTATE_PARSE;
+ str->curr_packet = p;
+ str->curr_packet_end = p + len;
+ str->hdr.win_left = str->hdr.win_right;
+ str->hdr.win_right = str->hdr.win_left + len;
+
+ return STREAM_OK;
+}
+
+bool parser_prepare_image(uint32_t time)
+{
+ struct stream_scan sk;
+ int tries;
+ int result;
+
+ stream_scan_init(&sk);
+
+ if (!str_send_msg(&video_str, STREAM_NEEDS_SYNC, time))
+ {
+ DEBUGF("Image was ready\n");
+ return true; /* Should already have the image */
+ }
+
+#ifdef HAVE_ADJUSTABLE_CPU_FREQ
+ rb->cpu_boost(true); /* No interference with trigger_cpu_boost */
+#endif
+
+ str_send_msg(&video_str, STREAM_RESET, 0);
+
+ sk.pos = parser_can_seek() ?
+ mpeg_parser_seek_PTS(time, video_str.id) : 0;
+ sk.len = sk.pos;
+ sk.dir = SSCAN_REVERSE;
+
+ tries = 1;
+try_again:
+
+ if (mpeg_parser_scan_start_code(&sk, MPEG_START_GOP))
+ {
+ DEBUGF("GOP found at: %ld\n", sk.pos);
+
+ unsigned id = mpeg_parser_scan_pes(&sk);
+
+ if (id != video_str.id && sk.pos > 0)
+ {
+ /* Not part of our stream */
+ DEBUGF(" wrong stream: 0x%02x\n", id);
+ goto try_again;
+ }
+
+ /* This will hit the PES header since it's known to be there */
+ uint32_t pts = mpeg_parser_scan_pts(&sk, id);
+
+ if (pts == INVALID_TIMESTAMP || pts > time)
+ {
+ DEBUGF(" wrong timestamp: %u\n", (unsigned)pts);
+ goto try_again;
+ }
+ }
+
+ str_parser.parms.sd.time = time;
+ str_parser.parms.sd.sk.pos = MAX(sk.pos, 0);
+ str_parser.parms.sd.sk.len = 1024*1024;
+ str_parser.parms.sd.sk.dir = SSCAN_FORWARD;
+
+ DEBUGF("thumb pos:%ld len:%ld\n", str_parser.parms.sd.sk.pos,
+ (long)str_parser.parms.sd.sk.len);
+
+ result = str_send_msg(&video_str, STREAM_SYNC,
+ (intptr_t)&str_parser.parms.sd);
+
+ if (result != STREAM_PERFECT_MATCH)
+ {
+ /* Two tries should be all that is nescessary to find the exact frame
+ * if the first GOP actually started later than the timestamp - the
+ * GOP just prior must then start on or earlier. */
+ if (++tries <= 2)
+ goto try_again;
+ }
+
+#ifdef HAVE_ADJUSTABLE_CPU_FREQ
+ rb->cpu_boost(false);
+#endif
+
+ return result > STREAM_OK;
+}
+
+/* Seek parser to the specified time and return absolute time.
+ * No actual hard stuff is performed here. That's done when streaming is
+ * about to begin or something from the current position is requested */
+uint32_t parser_seek_time(uint32_t time)
+{
+ if (!parser_can_seek())
+ time = 0;
+ else if (time > str_parser.duration)
+ time = str_parser.duration;
+
+ str_parser.last_seek_time = time + str_parser.start_pts;
+ return str_parser.last_seek_time;
+}
+
+void parser_prepare_streaming(void)
+{
+ struct stream_window sw;
+
+ DEBUGF("parser_prepare_streaming\n");
+
+ /* Prepare initial video frame */
+ parser_prepare_image(str_parser.last_seek_time);
+
+ /* Sync audio stream */
+ if (audio_str.start_pts != INVALID_TIMESTAMP)
+ prepare_audio(str_parser.last_seek_time);
+
+ /* Prequeue some data and set buffer window */
+ if (!stream_get_window(&sw))
+ sw.left = sw.right = disk_buf.filesize;
+
+ DEBUGF(" swl:%ld swr:%ld\n", sw.left, sw.right);
+
+ if (sw.right > disk_buf.filesize - 4*MIN_BUFAHEAD)
+ sw.right = disk_buf.filesize - 4*MIN_BUFAHEAD;
+
+ disk_buf_prepare_streaming(sw.left,
+ sw.right - sw.left + 4*MIN_BUFAHEAD);
+}
+
+int parser_init_stream(void)
+{
+ if (disk_buf.in_file < 0)
+ return STREAM_ERROR;
+
+ /* TODO: Actually find which streams are available */
+ audio_str.id = MPEG_STREAM_AUDIO_FIRST;
+ video_str.id = MPEG_STREAM_VIDEO_FIRST;
+
+ /* Try to pull a video PES - if not found, try video init anyway which
+ * should succeed if it really is a video-only stream */
+ video_str.hdr.pos = 0;
+ video_str.hdr.limit = 256*1024;
+
+ if (parse_demux(&video_str, STREAM_PM_RANDOM_ACCESS) == STREAM_OK)
+ {
+ /* Found a video packet - assume program stream */
+ str_parser.format = STREAM_FMT_MPEG_PS;
+ str_parser.next_data = parse_demux;
+ }
+ else
+ {
+ /* No PES element found - assume video elementary stream */
+ str_parser.format = STREAM_FMT_MPV;
+ str_parser.next_data = parse_elementary;
+ }
+
+ if (!init_video_info())
+ {
+ /* Cannot determine video size, etc. */
+ parser_init_state();
+ return STREAM_UNSUPPORTED;
+ }
+
+ if (str_parser.format == STREAM_FMT_MPEG_PS)
+ {
+ /* Initalize start_pts and end_pts with the length (in 45kHz units) of
+ * the movie. INVALID_TIMESTAMP if the time could not be determined */
+ if (!init_times(&video_str) || !check_times(&video_str))
+ {
+ /* Must have video at least */
+ parser_init_state();
+ return STREAM_UNSUPPORTED;
+ }
+
+ str_parser.flags |= STREAMF_CAN_SEEK;
+
+ if (init_times(&audio_str))
+ {
+ /* Audio will be part of playback pool */
+ stream_add_stream(&audio_str);
+
+ if (check_times(&audio_str))
+ {
+ /* Overall duration is maximum span */
+ str_parser.start_pts = MIN(audio_str.start_pts, video_str.start_pts);
+ str_parser.end_pts = MAX(audio_str.end_pts, video_str.end_pts);
+ }
+ else
+ {
+ /* Bad times on audio - use video times */
+ str_parser.start_pts = video_str.start_pts;
+ str_parser.end_pts = video_str.end_pts;
+
+ /* Questionable: could use bitrate seek and match video to that */
+ audio_str.start_pts = video_str.start_pts;
+ audio_str.end_pts = video_str.end_pts;
+ }
+ }
+ else
+ {
+ /* No audio stream - use video only */
+ str_parser.start_pts = video_str.start_pts;
+ str_parser.end_pts = video_str.end_pts;
+ }
+
+ str_parser.last_seek_time = str_parser.start_pts;
+ }
+ else
+ {
+ /* There's no way to handle times on this without a full file
+ * scan */
+ audio_str.start_pts = INVALID_TIMESTAMP;
+ audio_str.end_pts = INVALID_TIMESTAMP;
+ video_str.start_pts = 0;
+ video_str.end_pts = INVALID_TIMESTAMP;
+ str_parser.start_pts = 0;
+ str_parser.end_pts = INVALID_TIMESTAMP;
+ }
+
+ /* Add video to playback pool */
+ stream_add_stream(&video_str);
+
+ /* Cache duration - it's used very often */
+ str_parser.duration = str_parser.end_pts - str_parser.start_pts;
+
+ DEBUGF("Movie info:\n"
+ " size:%dx%d\n"
+ " start:%u\n"
+ " end:%u\n"
+ " duration:%u\n",
+ str_parser.dims.w, str_parser.dims.h,
+ (unsigned)str_parser.start_pts,
+ (unsigned)str_parser.end_pts,
+ (unsigned)str_parser.duration);
+
+ return STREAM_OK;
+}
+
+void parser_close_stream(void)
+{
+ stream_remove_streams();
+ parser_init_state();
+}
+
+bool parser_init(void)
+{
+ parser_init_state();
+ return true;
+}