From 02ddfeadbee52c1ad8c023a93594a8cb957e11db Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jan=20Ekstr=C3=B6m?= Date: Tue, 7 Feb 2023 21:37:10 +0200 Subject: [PATCH] avformat/movenc: allow writing out channel count in MP4 and 3GP MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ISOBMFF (14496-12) made this field ('channelcount') in the AudioSampleEntry structure non-template¹ somewhere before the release of the 2022 edition. As for ETSI TS 126 244 AKA 3GPP file format (V16.1.0, 2020-10), it does not seem contain any references limiting the channelcount entry in AudioSampleEntry or in its own definition of EVSSampleEntry. fate-mov-mp4-chapters test had to be adjusted as it output a mono vorbis stream, which would now be properly marked as such in the container. 1: As per 14496-12: Fields shown as “template” in the box descriptions are fields which are coded with a default value unless a derived specification defines their use and permits writers to use other values than the default. --- libavformat/movenc.c | 8 +------- tests/ref/fate/mov-mp4-chapters | 2 +- 2 files changed, 2 insertions(+), 8 deletions(-) diff --git a/libavformat/movenc.c b/libavformat/movenc.c index aca8b9d585..c4fcb5f8b1 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -1241,13 +1241,7 @@ static int mov_write_audio_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex avio_wb16(pb, 16); avio_wb16(pb, track->audio_vbr ? -2 : 0); /* compression ID */ } else { /* reserved for mp4/3gp */ - if (track->par->codec_id == AV_CODEC_ID_FLAC || - track->par->codec_id == AV_CODEC_ID_ALAC || - track->par->codec_id == AV_CODEC_ID_OPUS) { - avio_wb16(pb, track->par->ch_layout.nb_channels); - } else { - avio_wb16(pb, 2); - } + avio_wb16(pb, track->par->ch_layout.nb_channels); if (track->par->codec_id == AV_CODEC_ID_FLAC || track->par->codec_id == AV_CODEC_ID_ALAC) { avio_wb16(pb, track->par->bits_per_raw_sample); diff --git a/tests/ref/fate/mov-mp4-chapters b/tests/ref/fate/mov-mp4-chapters index 34f84de1b1..75cd3b3438 100644 --- a/tests/ref/fate/mov-mp4-chapters +++ b/tests/ref/fate/mov-mp4-chapters @@ -1,4 +1,4 @@ -1fd844c2f5bf77c3344e88e30ad994e1 *tests/data/fate/mov-mp4-chapters.mp4 +7b6aaa99c86fa1f5abfc9f242abcfffa *tests/data/fate/mov-mp4-chapters.mp4 111248 tests/data/fate/mov-mp4-chapters.mp4 #extradata 0: 3469, 0xc6769ddc #tb 0: 1/44100