From b81ed729ec1db32557174f569f076c6d6e04cb9f Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Sat, 10 Feb 2024 01:44:01 +0100 Subject: [PATCH] avformat/mov_chan: rework ff_mov_read_chnl A lot of changes and fixes to channel layout parsing, notably - get rid of dynamic allocation of channel positions - signal unimplemented speaker positions as unknown instead of failure, but warn the user about it - native order, and that a single channel only appears once was always assumed for less than 64 channels, obviously this was incorrect Signed-off-by: Marton Balint --- libavformat/mov_chan.c | 114 +++++++++++------------------------------ libavformat/mov_chan.h | 6 --- 2 files changed, 30 insertions(+), 90 deletions(-) diff --git a/libavformat/mov_chan.c b/libavformat/mov_chan.c index cce9d7a697..3e186b0837 100644 --- a/libavformat/mov_chan.c +++ b/libavformat/mov_chan.c @@ -804,66 +804,6 @@ int ff_mov_get_channel_positions_from_layout(const AVChannelLayout *layout, return 0; } -int ff_mov_get_layout_from_channel_positions(const uint8_t *position, int position_num, - AVChannelLayout *layout) -{ - int ret; - enum AVChannel channel; - - av_channel_layout_uninit(layout); - - if (position_num <= 63) { - layout->order = AV_CHANNEL_ORDER_NATIVE; - layout->nb_channels = position_num; - for (int i = 0; i < position_num; i++) { - if (position[i] >= FF_ARRAY_ELEMS(iso_channel_position)) { - ret = AVERROR_PATCHWELCOME; - goto error; - } - - channel = iso_channel_position[position[i]]; - // unsupported layout - if (channel == AV_CHAN_NONE) { - ret = AVERROR_PATCHWELCOME; - goto error; - } - - layout->u.mask |= 1ULL << channel; - } - } else { - layout->order = AV_CHANNEL_ORDER_CUSTOM; - layout->nb_channels = position_num; - layout->u.map = av_calloc(position_num, sizeof(*layout->u.map)); - if (!layout->u.map) { - ret = AVERROR(ENOMEM); - goto error; - } - - for (int i = 0; i < position_num; i++) { - if (position[i] >= FF_ARRAY_ELEMS(iso_channel_position)) { - ret = AVERROR_PATCHWELCOME; - goto error; - } - - channel = iso_channel_position[position[i]]; - // unsupported layout - if (channel == AV_CHAN_NONE) { - ret = AVERROR_PATCHWELCOME; - goto error; - } - - layout->u.map[i].id = channel; - } - } - - - return 0; - -error: - av_channel_layout_uninit(layout); - return ret; -} - int ff_mov_read_chnl(AVFormatContext *s, AVIOContext *pb, AVStream *st) { int stream_structure = avio_r8(pb); @@ -875,33 +815,39 @@ int ff_mov_read_chnl(AVFormatContext *s, AVIOContext *pb, AVStream *st) av_log(s, AV_LOG_TRACE, "'chnl' layout %d\n", layout); if (!layout) { - uint8_t *positions = av_malloc(st->codecpar->ch_layout.nb_channels); + AVChannelLayout *ch_layout = &st->codecpar->ch_layout; + int nb_channels = ch_layout->nb_channels; - if (!positions) - return AVERROR(ENOMEM); - for (int i = 0; i < st->codecpar->ch_layout.nb_channels; i++) { - int speaker_pos = avio_r8(pb); - - av_log(s, AV_LOG_TRACE, "speaker_position %d\n", speaker_pos); - if (speaker_pos == 126) { // explicit position - avpriv_request_sample(s, "explicit position"); - av_freep(&positions); - return AVERROR_PATCHWELCOME; - } else { - positions[i] = speaker_pos; - } - } - - ret = ff_mov_get_layout_from_channel_positions(positions, - st->codecpar->ch_layout.nb_channels, - &st->codecpar->ch_layout); - av_freep(&positions); - if (ret) { - av_log(s, AV_LOG_ERROR, - "get channel layout from speaker positions failed, %s\n", - av_err2str(ret)); + av_channel_layout_uninit(ch_layout); + ret = av_channel_layout_custom_init(ch_layout, nb_channels); + if (ret < 0) return ret; + + for (int i = 0; i < nb_channels; i++) { + int speaker_pos = avio_r8(pb); + enum AVChannel channel; + + if (speaker_pos == 126) // explicit position + avio_skip(pb, 3); // azimuth, elevation + + if (speaker_pos >= FF_ARRAY_ELEMS(iso_channel_position)) + channel = AV_CHAN_NONE; + else + channel = iso_channel_position[speaker_pos]; + + if (channel == AV_CHAN_NONE) { + av_log(s, AV_LOG_WARNING, "speaker position %d is not implemented\n", speaker_pos); + channel = AV_CHAN_UNKNOWN; + } + + ch_layout->u.map[i].id = channel; } + + ret = av_channel_layout_retype(ch_layout, AV_CHANNEL_ORDER_NATIVE, AV_CHANNEL_LAYOUT_RETYPE_FLAG_LOSSLESS); + if (ret == AVERROR(ENOSYS)) + ret = av_channel_layout_retype(ch_layout, AV_CHANNEL_ORDER_UNSPEC, AV_CHANNEL_LAYOUT_RETYPE_FLAG_LOSSLESS); + if (ret < 0 && ret != AVERROR(ENOSYS)) + return ret; } else { uint64_t omitted_channel_map = avio_rb64(pb); diff --git a/libavformat/mov_chan.h b/libavformat/mov_chan.h index b7d435b99f..e480809c44 100644 --- a/libavformat/mov_chan.h +++ b/libavformat/mov_chan.h @@ -183,12 +183,6 @@ int ff_mov_get_channel_layout_from_config(int config, AVChannelLayout *layout); int ff_mov_get_channel_positions_from_layout(const AVChannelLayout *layout, uint8_t *position, int position_num); -/** - * Get AVChannelLayout from ISO/IEC 23001-8 OutputChannelPosition. - */ -int ff_mov_get_layout_from_channel_positions(const uint8_t *position, int position_num, - AVChannelLayout *layout); - /** * Read 'chnl' tag from the input stream. *