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-rw-r--r--apps/codecs/libasf/asf.c354
1 files changed, 354 insertions, 0 deletions
diff --git a/apps/codecs/libasf/asf.c b/apps/codecs/libasf/asf.c
new file mode 100644
index 0000000000..f65627b057
--- /dev/null
+++ b/apps/codecs/libasf/asf.c
@@ -0,0 +1,354 @@
+#include <inttypes.h>
+#include "codeclib.h"
+#include "asf.h"
+
+/* Read an unaligned 32-bit little endian long from buffer. */
+static unsigned long get_long_le(void* buf)
+{
+ unsigned char* p = (unsigned char*) buf;
+
+ return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
+}
+
+/* Read an unaligned 16-bit little endian short from buffer. */
+static unsigned short get_short_le(void* buf)
+{
+ unsigned char* p = (unsigned char*) buf;
+
+ return p[0] | (p[1] << 8);
+}
+
+#define GETLEN2b(bits) (((bits) == 0x03) ? 4 : bits)
+
+#define GETVALUE2b(bits, data) \
+ (((bits) != 0x03) ? ((bits) != 0x02) ? ((bits) != 0x01) ? \
+ 0 : *(data) : get_short_le(data) : get_long_le(data))
+
+int asf_read_packet(uint8_t** audiobuf, int* audiobufsize, int* packetlength,
+ asf_waveformatex_t* wfx, struct codec_api* ci)
+{
+ uint8_t tmp8, packet_flags, packet_property;
+ int stream_id;
+ int ec_length, opaque_data, ec_length_type;
+ int datalen;
+ uint8_t data[18];
+ uint8_t* datap;
+ uint32_t length;
+ uint32_t padding_length;
+ uint32_t send_time;
+ uint16_t duration;
+ uint16_t payload_count;
+ int payload_length_type;
+ uint32_t payload_hdrlen;
+ int payload_datalen;
+ int multiple;
+ uint32_t replicated_length;
+ uint32_t media_object_number;
+ uint32_t media_object_offset;
+ uint32_t bytesread = 0;
+ uint8_t* buf;
+ size_t bufsize;
+ int i;
+ /*DEBUGF("Reading new packet at %d bytes ", (int)ci->curpos);*/
+
+ if (ci->read_filebuf(&tmp8, 1) == 0) {
+ return ASF_ERROR_EOF;
+ }
+ bytesread++;
+
+ /* TODO: We need a better way to detect endofstream */
+ if (tmp8 != 0x82) {
+ DEBUGF("Read failed: packet did not sync\n");
+ return -1;
+ }
+
+
+ if (tmp8 & 0x80) {
+ ec_length = tmp8 & 0x0f;
+ opaque_data = (tmp8 >> 4) & 0x01;
+ ec_length_type = (tmp8 >> 5) & 0x03;
+
+ if (ec_length_type != 0x00 || opaque_data != 0 || ec_length != 0x02) {
+ DEBUGF("incorrect error correction flags\n");
+ return ASF_ERROR_INVALID_VALUE;
+ }
+
+ /* Skip ec_data */
+ ci->advance_buffer(ec_length);
+ bytesread += ec_length;
+ } else {
+ ec_length = 0;
+ }
+
+ if (ci->read_filebuf(&packet_flags, 1) == 0) { return ASF_ERROR_EOF; }
+ if (ci->read_filebuf(&packet_property, 1) == 0) { return ASF_ERROR_EOF; }
+ bytesread += 2;
+
+ datalen = GETLEN2b((packet_flags >> 1) & 0x03) +
+ GETLEN2b((packet_flags >> 3) & 0x03) +
+ GETLEN2b((packet_flags >> 5) & 0x03) + 6;
+
+#if 0
+ if (datalen > sizeof(data)) {
+ DEBUGF("Unexpectedly long datalen in data - %d\n",datalen);
+ return ASF_ERROR_OUTOFMEM;
+ }
+#endif
+
+ if (ci->read_filebuf(data, datalen) == 0) {
+ return ASF_ERROR_EOF;
+ }
+
+ bytesread += datalen;
+
+ datap = data;
+ length = GETVALUE2b((packet_flags >> 5) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 5) & 0x03);
+ /* sequence value is not used */
+ GETVALUE2b((packet_flags >> 1) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 1) & 0x03);
+ padding_length = GETVALUE2b((packet_flags >> 3) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 3) & 0x03);
+ send_time = get_long_le(datap);
+ datap += 4;
+ duration = get_short_le(datap);
+ datap += 2;
+ /*DEBUGF("and duration %d ms\n", duration);*/
+
+ /* this is really idiotic, packet length can (and often will) be
+ * undefined and we just have to use the header packet size as the size
+ * value */
+ if (!((packet_flags >> 5) & 0x03)) {
+ length = wfx->packet_size;
+ }
+
+ /* this is also really idiotic, if packet length is smaller than packet
+ * size, we need to manually add the additional bytes into padding length
+ */
+ if (length < wfx->packet_size) {
+ padding_length += wfx->packet_size - length;
+ length = wfx->packet_size;
+ }
+
+ if (length > wfx->packet_size) {
+ DEBUGF("packet with too big length value\n");
+ return ASF_ERROR_INVALID_LENGTH;
+ }
+
+ /* check if we have multiple payloads */
+ if (packet_flags & 0x01) {
+ if (ci->read_filebuf(&tmp8, 1) == 0) {
+ return ASF_ERROR_EOF;
+ }
+ payload_count = tmp8 & 0x3f;
+ payload_length_type = (tmp8 >> 6) & 0x03;
+ bytesread++;
+ } else {
+ payload_count = 1;
+ payload_length_type = 0x02; /* not used */
+ }
+
+ if (length < bytesread) {
+ DEBUGF("header exceeded packet size, invalid file - length=%d, bytesread=%d\n",(int)length,(int)bytesread);
+ /* FIXME: should this be checked earlier? */
+ return ASF_ERROR_INVALID_LENGTH;
+ }
+
+
+ /* We now parse the individual payloads, and move all payloads
+ belonging to our audio stream to a contiguous block, starting at
+ the location of the first payload.
+ */
+
+ *audiobuf = NULL;
+ *audiobufsize = 0;
+ *packetlength = length - bytesread;
+
+ buf = ci->request_buffer(&bufsize, length);
+ datap = buf;
+
+ if (bufsize != length) {
+ /* This should only happen with packets larger than 32KB (the
+ guard buffer size). All the streams I've seen have
+ relatively small packets less than about 8KB), but I don't
+ know what is expected.
+ */
+ DEBUGF("Could not read packet (requested %d bytes, received %d), curpos=%d, aborting\n",
+ (int)length,(int)bufsize,(int)ci->curpos);
+ return -1;
+ }
+
+ for (i=0; i<payload_count; i++) {
+ stream_id = datap[0]&0x7f;
+ datap++;
+ bytesread++;
+
+ payload_hdrlen = GETLEN2b(packet_property & 0x03) +
+ GETLEN2b((packet_property >> 2) & 0x03) +
+ GETLEN2b((packet_property >> 4) & 0x03);
+
+ //DEBUGF("payload_hdrlen = %d\n",payload_hdrlen);
+#if 0
+ /* TODO */
+ if (payload_hdrlen > size) {
+ return ASF_ERROR_INVALID_LENGTH;
+ }
+#endif
+ if (payload_hdrlen > sizeof(data)) {
+ DEBUGF("Unexpectedly long datalen in data - %d\n",datalen);
+ return ASF_ERROR_OUTOFMEM;
+ }
+
+ bytesread += payload_hdrlen;
+ media_object_number = GETVALUE2b((packet_property >> 4) & 0x03, datap);
+ datap += GETLEN2b((packet_property >> 4) & 0x03);
+ media_object_offset = GETVALUE2b((packet_property >> 2) & 0x03, datap);
+ datap += GETLEN2b((packet_property >> 2) & 0x03);
+ replicated_length = GETVALUE2b(packet_property & 0x03, datap);
+ datap += GETLEN2b(packet_property & 0x03);
+
+ /* TODO: Validate replicated_length */
+ /* TODO: Is the content of this important for us? */
+ datap += replicated_length;
+ bytesread += replicated_length;
+
+ multiple = packet_flags & 0x01;
+
+
+ if (multiple) {
+ int x;
+
+ x = GETLEN2b(payload_length_type);
+
+ if (x != 2) {
+ /* in multiple payloads datalen should be a word */
+ return ASF_ERROR_INVALID_VALUE;
+ }
+
+#if 0
+ if (skip + tmp > datalen) {
+ /* not enough data */
+ return ASF_ERROR_INVALID_LENGTH;
+ }
+#endif
+ payload_datalen = GETVALUE2b(payload_length_type, datap);
+ datap += x;
+ bytesread += x;
+ } else {
+ payload_datalen = length - bytesread - padding_length;
+ }
+
+ if (replicated_length==1)
+ datap++;
+
+ if (stream_id == wfx->audiostream)
+ {
+ if (*audiobuf == NULL) {
+ /* The first payload can stay where it is */
+ *audiobuf = datap;
+ *audiobufsize = payload_datalen;
+ } else {
+ /* The second and subsequent payloads in this packet
+ that belong to the audio stream need to be moved to be
+ contiguous with the first payload.
+ */
+ memmove(*audiobuf + *audiobufsize, datap, payload_datalen);
+ *audiobufsize += payload_datalen;
+ }
+ }
+ datap += payload_datalen;
+ bytesread += payload_datalen;
+ }
+
+ if (*audiobuf != NULL)
+ return 1;
+ else
+ return 0;
+}
+
+
+int asf_get_timestamp(int *duration, struct codec_api* ci)
+{
+ uint8_t tmp8, packet_flags, packet_property;
+ int ec_length, opaque_data, ec_length_type;
+ int datalen;
+ uint8_t data[18];
+ uint8_t* datap;
+ uint32_t length;
+ uint32_t padding_length;
+ uint32_t send_time;
+ static int packet_count = 0;
+
+ uint32_t bytesread = 0;
+ packet_count++;
+ if (ci->read_filebuf(&tmp8, 1) == 0) {
+ DEBUGF("ASF ERROR (EOF?)\n");
+ return ASF_ERROR_EOF;
+ }
+ bytesread++;
+
+ /* TODO: We need a better way to detect endofstream */
+ if (tmp8 != 0x82) {
+ DEBUGF("Get timestamp: Detected end of stream\n");
+ return ASF_ERROR_EOF;
+ }
+
+
+ if (tmp8 & 0x80) {
+ ec_length = tmp8 & 0x0f;
+ opaque_data = (tmp8 >> 4) & 0x01;
+ ec_length_type = (tmp8 >> 5) & 0x03;
+
+ if (ec_length_type != 0x00 || opaque_data != 0 || ec_length != 0x02) {
+ DEBUGF("incorrect error correction flags\n");
+ return ASF_ERROR_INVALID_VALUE;
+ }
+
+ /* Skip ec_data */
+ ci->advance_buffer(ec_length);
+ bytesread += ec_length;
+ } else {
+ ec_length = 0;
+ }
+
+ if (ci->read_filebuf(&packet_flags, 1) == 0) {
+ DEBUGF("Detected end of stream 2\n");
+ return ASF_ERROR_EOF;
+ }
+
+ if (ci->read_filebuf(&packet_property, 1) == 0) {
+ DEBUGF("Detected end of stream3\n");
+ return ASF_ERROR_EOF;
+ }
+ bytesread += 2;
+
+ datalen = GETLEN2b((packet_flags >> 1) & 0x03) +
+ GETLEN2b((packet_flags >> 3) & 0x03) +
+ GETLEN2b((packet_flags >> 5) & 0x03) + 6;
+
+ if (ci->read_filebuf(data, datalen) == 0) {
+ DEBUGF("Detected end of stream4\n");
+ return ASF_ERROR_EOF;
+ }
+
+ bytesread += datalen;
+
+ datap = data;
+ length = GETVALUE2b((packet_flags >> 5) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 5) & 0x03);
+
+ /* sequence value is not used */
+ GETVALUE2b((packet_flags >> 1) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 1) & 0x03);
+ padding_length = GETVALUE2b((packet_flags >> 3) & 0x03, datap);
+ datap += GETLEN2b((packet_flags >> 3) & 0x03);
+ send_time = get_long_le(datap);
+ datap += 4;
+ *duration = get_short_le(datap);
+
+ /*the asf_get_timestamp function advances us 12-13 bytes past the packet start,
+ need to undo this here so that we stay synced with the packet*/
+ ci->seek_buffer(ci->curpos-bytesread);
+
+ return send_time;
+}