For ipcm and fpcm streams, big-endian format is the default, but it can be
changed
with additional 'pcmC' sub-atom of audio sample description.
Details can be found in ISO/IEC 23003-5:2020
Fixes ticket #9763
Fixes ticket #9790
---
libavformat/mov.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
diff --git a/libavformat/mov.c b/libavformat/mov.c
index d7be593a86..f71a470d9c 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -7567,6 +7567,65 @@ static int mov_read_iloc(MOVContext *c, AVIOContext *pb,
MOVAtom atom)
return atom.size;
}
+static int mov_read_pcmc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+ int version, format_flags, pcm_sample_size;
+ AVStream *st;
+
+ if (atom.size < 6) {
+ av_log(c->fc, AV_LOG_ERROR, "Empty pcmC box\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ version = avio_r8(pb);
+ if (version) {
+ av_log(c->fc, AV_LOG_WARNING, "Unsupported pcmC box version %d\n",
version);
+ return 0;
+ }
+
+ avio_rb24(pb); // flags
+
+ if (c->fc->nb_streams < 1)
+ return 0;
+ st = c->fc->streams[c->fc->nb_streams-1];
+ if (!st || !st->codecpar)
+ return 0;
+
+ format_flags = avio_r8(pb);
+ if (format_flags == 1) { // indicates little-endian format. If not
present, big-endian format is used
+ if (st->codecpar->codec_tag == MKTAG('i','p','c','m')) {
+ switch (st->codecpar->codec_id) {
+ case AV_CODEC_ID_PCM_S16BE:
+ st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
+ break;
+ case AV_CODEC_ID_PCM_S24BE:
+ st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE;
+ break;
+ case AV_CODEC_ID_PCM_S32BE:
+ st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE;
+ break;
+ }
+ }
+ else if (st->codecpar->codec_tag == MKTAG('f','p','c','m')) {
+ switch (st->codecpar->codec_id) {
+ case AV_CODEC_ID_PCM_F32BE:
+ st->codecpar->codec_id = AV_CODEC_ID_PCM_F32LE;
+ break;
+ case AV_CODEC_ID_PCM_F64BE:
+ st->codecpar->codec_id = AV_CODEC_ID_PCM_F64LE;
+ break;
+ }
+ }
+ }
+
+ pcm_sample_size = avio_r8(pb);
+ if (pcm_sample_size != st->codecpar->bits_per_coded_sample) {
+ av_log(c->fc, AV_LOG_WARNING, "Unexpected pcmC sample size (%d vs
%d)\n", pcm_sample_size, st->codecpar->bits_per_coded_sample);
+ }
+
+ return 0;
+}
+
static const MOVParseTableEntry mov_default_parse_table[] = {
{ MKTAG('A','C','L','R'), mov_read_aclr },
{ MKTAG('A','P','R','G'), mov_read_avid },
@@ -7670,6 +7729,7 @@ static const MOVParseTableEntry mov_default_parse_table[]
= {
{ MKTAG('S','A','3','D'), mov_read_SA3D }, /* ambisonic audio box */
{ MKTAG('S','A','N','D'), mov_read_SAND }, /* non diegetic audio box */
{ MKTAG('i','l','o','c'), mov_read_iloc },
+{ MKTAG('p','c','m','C'), mov_read_pcmc }, /* PCM configuration box */
{ 0, NULL }
};
--
2.35.1
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