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-rw-r--r--gst/audioparsers/gstmpegaudioparse.c168
-rw-r--r--gst/audioparsers/gstmpegaudioparse.h2
2 files changed, 156 insertions, 14 deletions
diff --git a/gst/audioparsers/gstmpegaudioparse.c b/gst/audioparsers/gstmpegaudioparse.c
index efb97587a..a8c68252c 100644
--- a/gst/audioparsers/gstmpegaudioparse.c
+++ b/gst/audioparsers/gstmpegaudioparse.c
@@ -200,6 +200,7 @@ gst_mpeg_audio_parse_reset (GstMpegAudioParse * mp3parse)
mp3parse->sent_codec_tag = FALSE;
mp3parse->last_posted_crc = CRC_UNKNOWN;
mp3parse->last_posted_channel_mode = MPEG_AUDIO_CHANNEL_MODE_UNKNOWN;
+ mp3parse->freerate = 0;
mp3parse->hdr_bitrate = 0;
@@ -307,14 +308,16 @@ mp3_type_frame_length_from_header (GstMpegAudioParse * mp3parse, guint32 header,
bitrate = (header >> 12) & 0xF;
bitrate = mp3types_bitrates[lsf][layer - 1][bitrate] * 1000;
- /* The caller has ensured we have a valid header, so bitrate can't be
- zero here. */
- g_assert (bitrate != 0);
+ if (!bitrate) {
+ GST_LOG_OBJECT (mp3parse, "using freeform bitrate");
+ bitrate = mp3parse->freerate;
+ }
samplerate = (header >> 10) & 0x3;
samplerate = mp3types_freqs[lsf + mpg25][samplerate];
- padding = (header >> 9) & 0x1;
+ /* force 0 length if 0 bitrate */
+ padding = (bitrate > 0) ? (header >> 9) & 0x1 : 0;
mode = (header >> 6) & 0x3;
channels = (mode == 3) ? 1 : 2;
@@ -419,8 +422,7 @@ gst_mp3parse_validate_extended (GstMpegAudioParse * mp3parse, GstBuffer * buf,
(guint) next_header & HDRMASK, bpf);
*valid = FALSE;
return TRUE;
- } else if ((((next_header >> 12) & 0xf) == 0) ||
- (((next_header >> 12) & 0xf) == 0xf)) {
+ } else if (((next_header >> 12) & 0xf) == 0xf) {
/* The essential parts were the same, but the bitrate held an
invalid value - also reject */
GST_DEBUG_OBJECT (mp3parse, "next header invalid (bitrate)");
@@ -431,6 +433,13 @@ gst_mp3parse_validate_extended (GstMpegAudioParse * mp3parse, GstBuffer * buf,
bpf = mp3_type_frame_length_from_header (mp3parse, next_header,
NULL, NULL, NULL, NULL, NULL, NULL, NULL);
+ /* if no bitrate, and no freeform rate known, then fail */
+ if (G_UNLIKELY (!bpf)) {
+ GST_DEBUG_OBJECT (mp3parse, "next header invalid (bitrate 0)");
+ *valid = FALSE;
+ return TRUE;
+ }
+
offset += bpf;
frames_found++;
}
@@ -461,11 +470,6 @@ gst_mpeg_audio_parse_head_check (GstMpegAudioParse * mp3parse,
return FALSE;
}
/* if it's an invalid bitrate */
- if (((head >> 12) & 0xf) == 0x0) {
- GST_WARNING_OBJECT (mp3parse, "invalid bitrate: 0x%lx."
- "Free format files are not supported yet", (head >> 12) & 0xf);
- return FALSE;
- }
if (((head >> 12) & 0xf) == 0xf) {
GST_WARNING_OBJECT (mp3parse, "invalid bitrate: 0x%lx", (head >> 12) & 0xf);
return FALSE;
@@ -486,6 +490,115 @@ gst_mpeg_audio_parse_head_check (GstMpegAudioParse * mp3parse,
return TRUE;
}
+/* Determines possible freeform frame rate/size by looking for next
+ * header with valid bitrate (0 or otherwise valid) (and sufficiently
+ * matching current header).
+ *
+ * Returns TRUE if we've found such one, and *rate then contains rate
+ * (or *rate contains 0 if decided no freeframe size could be determined).
+ * If not enough data, returns FALSE.
+ */
+static gboolean
+gst_mp3parse_find_freerate (GstMpegAudioParse * mp3parse, GstBuffer * buf,
+ guint32 header, gboolean at_eos, gint * _rate)
+{
+ guint32 next_header;
+ const guint8 *data;
+ guint available;
+ int offset = 4;
+ gulong samplerate, rate, layer, padding;
+ gboolean valid;
+ gint lsf, mpg25;
+
+ available = GST_BUFFER_SIZE (buf);
+ data = GST_BUFFER_DATA (buf);
+
+ *_rate = 0;
+
+ /* pick apart header again partially */
+ if (header & (1 << 20)) {
+ lsf = (header & (1 << 19)) ? 0 : 1;
+ mpg25 = 0;
+ } else {
+ lsf = 1;
+ mpg25 = 1;
+ }
+ layer = 4 - ((header >> 17) & 0x3);
+ samplerate = (header >> 10) & 0x3;
+ samplerate = mp3types_freqs[lsf + mpg25][samplerate];
+ padding = (header >> 9) & 0x1;
+
+ for (; offset < available; ++offset) {
+ /* Check if we have enough data for all these frames, plus the next
+ frame header. */
+ if (available < offset + 4) {
+ if (at_eos) {
+ /* Running out of data; failed to determine size */
+ return TRUE;
+ } else {
+ return FALSE;
+ }
+ }
+
+ valid = FALSE;
+ next_header = GST_READ_UINT32_BE (data + offset);
+ if ((next_header & 0xFFE00000) != 0xFFE00000)
+ goto next;
+
+ GST_DEBUG_OBJECT (mp3parse, "At %d: header=%08X, header2=%08X",
+ offset, (unsigned int) header, (unsigned int) next_header);
+
+ if ((next_header & HDRMASK) != (header & HDRMASK)) {
+ /* If any of the unmasked bits don't match, then it's not valid */
+ GST_DEBUG_OBJECT (mp3parse, "next header doesn't match "
+ "(header=%08X (%08X), header2=%08X (%08X))",
+ (guint) header, (guint) header & HDRMASK, (guint) next_header,
+ (guint) next_header & HDRMASK);
+ goto next;
+ } else if (((next_header >> 12) & 0xf) == 0xf) {
+ /* The essential parts were the same, but the bitrate held an
+ invalid value - also reject */
+ GST_DEBUG_OBJECT (mp3parse, "next header invalid (bitrate)");
+ goto next;
+ }
+
+ valid = TRUE;
+
+ next:
+ /* almost accept as free frame */
+ if (layer == 1) {
+ rate = samplerate * (offset - 4 * padding + 4) / 48000;
+ } else {
+ rate = samplerate * (offset - padding + 1) / (144 >> lsf) / 1000;
+ }
+
+ if (valid) {
+ GST_LOG_OBJECT (mp3parse, "calculated rate %d", rate * 1000);
+ if (rate < 8 || (layer == 3 && rate > 640)) {
+ GST_DEBUG_OBJECT (mp3parse, "rate invalid");
+ if (rate < 8) {
+ /* maybe some hope */
+ continue;
+ } else {
+ GST_DEBUG_OBJECT (mp3parse, "aborting");
+ /* give up */
+ break;
+ }
+ }
+ *_rate = rate * 1000;
+ break;
+ } else {
+ /* avoid indefinite searching */
+ if (rate > 1000) {
+ GST_DEBUG_OBJECT (mp3parse, "exceeded sanity rate; aborting");
+ break;
+ }
+ }
+ }
+
+ return TRUE;
+}
+
static gboolean
gst_mpeg_audio_parse_check_valid_frame (GstBaseParse * parse,
GstBaseParseFrame * frame, guint * framesize, gint * skipsize)
@@ -527,9 +640,14 @@ gst_mpeg_audio_parse_check_valid_frame (GstBaseParse * parse,
GST_LOG_OBJECT (parse, "got frame");
+ lost_sync = GST_BASE_PARSE_LOST_SYNC (parse);
+ draining = GST_BASE_PARSE_DRAINING (parse);
+
+ if (G_UNLIKELY (lost_sync))
+ mp3parse->freerate = 0;
+
bpf = mp3_type_frame_length_from_header (mp3parse, header,
&version, &layer, &channels, &bitrate, &rate, &mode, &crc);
- g_assert (bpf != 0);
if (channels != mp3parse->channels || rate != mp3parse->rate ||
layer != mp3parse->layer || version != mp3parse->version)
@@ -537,8 +655,30 @@ gst_mpeg_audio_parse_check_valid_frame (GstBaseParse * parse,
else
caps_change = FALSE;
- lost_sync = GST_BASE_PARSE_LOST_SYNC (parse);
- draining = GST_BASE_PARSE_DRAINING (parse);
+ /* maybe free format */
+ if (bpf == 0) {
+ GST_LOG_OBJECT (mp3parse, "possibly free format");
+ if (lost_sync || mp3parse->freerate == 0) {
+ GST_DEBUG_OBJECT (mp3parse, "finding free format rate");
+ if (!gst_mp3parse_find_freerate (mp3parse, buf, header, draining, &valid)) {
+ /* not enough data */
+ *framesize = G_MAXUINT;
+ *skipsize = 0;
+ return FALSE;
+ } else {
+ GST_DEBUG_OBJECT (parse, "determined freeform size %d", valid);
+ mp3parse->freerate = valid;
+ }
+ }
+ /* try again */
+ bpf = mp3_type_frame_length_from_header (mp3parse, header,
+ &version, &layer, &channels, &bitrate, &rate, &mode, &crc);
+ if (!bpf) {
+ /* did not come up with valid freeform length, reject after all */
+ *skipsize = 1;
+ return FALSE;
+ }
+ }
if (!draining && (lost_sync || caps_change)) {
if (!gst_mp3parse_validate_extended (mp3parse, buf, header, bpf, draining,
diff --git a/gst/audioparsers/gstmpegaudioparse.h b/gst/audioparsers/gstmpegaudioparse.h
index 758000130..6b4267355 100644
--- a/gst/audioparsers/gstmpegaudioparse.h
+++ b/gst/audioparsers/gstmpegaudioparse.h
@@ -60,6 +60,8 @@ struct _GstMpegAudioParse {
/* samples per frame */
gint spf;
+ gint freerate;
+
gboolean sent_codec_tag;
guint last_posted_bitrate;
gint last_posted_crc, last_crc;
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-26 22:58:36 +0000