[FFmpeg-devel] [PATCH] aacdec_usac: correctly set and use the layout map
Paul B Mahol
onemda at gmail.com
Thu Jun 6 18:54:44 EEST 2024
On Wed, Jun 5, 2024 at 7:41 PM Lynne via ffmpeg-devel <
ffmpeg-devel at ffmpeg.org> wrote:
> ---
> libavcodec/aac/aacdec_usac.c | 105 +++++++++++++++++++++--------------
> 1 file changed, 63 insertions(+), 42 deletions(-)
>
> diff --git a/libavcodec/aac/aacdec_usac.c b/libavcodec/aac/aacdec_usac.c
> index 04dd5facff..561734f930 100644
> --- a/libavcodec/aac/aacdec_usac.c
> +++ b/libavcodec/aac/aacdec_usac.c
> @@ -268,17 +268,25 @@ int ff_aac_usac_reset_state(AACDecContext *ac,
> OutputConfiguration *oc)
> /* Initialize state */
> for (int i = 0; i < usac->nb_elems; i++) {
> AACUsacElemConfig *e = &usac->elems[i];
> - if (e->type != ID_USAC_SCE && e->type != ID_USAC_CPE)
> + if (e->type == ID_USAC_EXT)
> continue;
>
> - if (e->type == ID_USAC_SCE) {
> + switch (e->type) {
> + case ID_USAC_SCE:
> ch = 1;
> type = TYPE_SCE;
> id = elem_id[0]++;
> - } else {
> + break;
> + case ID_USAC_CPE:
> ch = 2;
> type = TYPE_CPE;
> id = elem_id[1]++;
> + break;
> + case ID_USAC_LFE:
> + ch = 1;
> + type = TYPE_LFE;
> + id = elem_id[2]++;
> + break;
> }
>
> che = ff_aac_get_che(ac, type, id);
> @@ -318,7 +326,8 @@ int ff_aac_usac_config_decode(AACDecContext *ac,
> AVCodecContext *avctx,
> AACUSACConfig *usac = &oc->usac;
> int elem_id[3 /* SCE, CPE, LFE */];
>
> - uint8_t layout_map[MAX_ELEM_ID*4][3];
> + int map_pos_set = 0;
> + uint8_t layout_map[MAX_ELEM_ID*4][3] = { 0 };
>
> memset(usac, 0, sizeof(*usac));
>
> @@ -391,6 +400,8 @@ int ff_aac_usac_config_decode(AACDecContext *ac,
> AVCodecContext *avctx,
> /* Fill in the number of expected channels */
> for (int i = 0; i < nb_elements; i++)
> nb_channels += layout_map[i][0] == TYPE_CPE ? 2 : 1;
> +
> + map_pos_set = 1;
> }
>
> /* UsacDecoderConfig */
> @@ -404,12 +415,12 @@ int ff_aac_usac_config_decode(AACDecContext *ac,
> AVCodecContext *avctx,
> }
>
> for (int i = 0; i < usac->nb_elems; i++) {
> + int map_count = elem_id[0] + elem_id[1] + elem_id[2];
> AACUsacElemConfig *e = &usac->elems[i];
> memset(e, 0, sizeof(*e));
>
> e->type = get_bits(gb, 2); /* usacElementType */
> - if (e->type != ID_USAC_EXT &&
> - (elem_id[0] + elem_id[1] + elem_id[2] + 1) > nb_channels) {
> + if (e->type != ID_USAC_EXT && (map_count + 1) > nb_channels) {
> av_log(ac->avctx, AV_LOG_ERROR, "Too many channels for the
> channel "
> "configuration\n");
> usac->nb_elems = 0;
> @@ -425,30 +436,31 @@ int ff_aac_usac_config_decode(AACDecContext *ac,
> AVCodecContext *avctx,
> decode_usac_element_core(e, gb, sbr_ratio);
> if (e->sbr.ratio > 0)
> decode_usac_sbr_data(e, gb);
> - layout_map[i][0] = TYPE_SCE;
> - layout_map[i][1] = i;
> - layout_map[i][2] = AAC_CHANNEL_FRONT;
> - elem_id[0]++;
> + layout_map[map_count][0] = TYPE_SCE;
> + layout_map[map_count][1] = elem_id[0]++;
> + if (!map_pos_set)
> + layout_map[map_count][2] = AAC_CHANNEL_FRONT;
>
> break;
> case ID_USAC_CPE: /* UsacChannelPairElementConf */
> /* UsacCoreConfig */
> decode_usac_element_core(e, gb, sbr_ratio);
> decode_usac_element_pair(e, gb);
> - layout_map[i][0] = TYPE_CPE;
> - layout_map[i][1] = i;
> - layout_map[i][2] = AAC_CHANNEL_FRONT;
> - elem_id[1]++;
> + layout_map[map_count][0] = TYPE_CPE;
> + layout_map[map_count][1] = elem_id[1]++;
> + if (!map_pos_set)
> + layout_map[map_count][2] = AAC_CHANNEL_FRONT;
>
> break;
> case ID_USAC_LFE: /* LFE */
> /* LFE has no need for any configuration */
> e->tw_mdct = 0;
> e->noise_fill = 0;
> - layout_map[i][0] = TYPE_LFE;
> - layout_map[i][1] = i;
> - layout_map[i][2] = AAC_CHANNEL_LFE;
> - elem_id[2]++;
> + layout_map[map_count][0] = TYPE_LFE;
> + layout_map[map_count][1] = elem_id[2]++;
> + if (!map_pos_set)
> + layout_map[map_count][2] = AAC_CHANNEL_LFE;
> +
> break;
> case ID_USAC_EXT: /* EXT */
> ret = decode_usac_extension(ac, e, gb);
> @@ -458,7 +470,8 @@ int ff_aac_usac_config_decode(AACDecContext *ac,
> AVCodecContext *avctx,
> };
> }
>
> - ret = ff_aac_output_configure(ac, layout_map, elem_id[0] + elem_id[1]
> + elem_id[2], OC_GLOBAL_HDR, 0);
> + ret = ff_aac_output_configure(ac, layout_map, elem_id[0] + elem_id[1]
> + elem_id[2],
> + OC_GLOBAL_HDR, 0);
> if (ret < 0) {
> av_log(avctx, AV_LOG_ERROR, "Unable to parse channel config!\n");
> usac->nb_elems = 0;
> @@ -1531,9 +1544,11 @@ static int parse_ext_ele(AACDecContext *ac,
> AACUsacElemConfig *e,
> int ff_aac_usac_decode_frame(AVCodecContext *avctx, AACDecContext *ac,
> GetBitContext *gb, int *got_frame_ptr)
> {
> - int ret, nb_ch_el, is_dmono = 0;
> + int ret, is_dmono = 0;
> int indep_flag, samples = 0;
> - int audio_found = 0, sce_count = 0;
> + int audio_found = 0;
> + int elem_id[3 /* SCE, CPE, LFE */] = { 0, 0, 0 };
> +
> AVFrame *frame = ac->frame;
>
> ff_aac_output_configure(ac, ac->oc[1].layout_map,
> ac->oc[1].layout_map_tags,
> @@ -1543,42 +1558,46 @@ int ff_aac_usac_decode_frame(AVCodecContext
> *avctx, AACDecContext *ac,
>
> indep_flag = get_bits1(gb);
>
> - nb_ch_el = 0;
> for (int i = 0; i < ac->oc[1].usac.nb_elems; i++) {
> + int layout_id;
> + int layout_type;
> AACUsacElemConfig *e = &ac->oc[1].usac.elems[i];
> ChannelElement *che;
>
> + if (e->type == ID_USAC_SCE) {
> + layout_id = elem_id[0]++;
> + layout_type = TYPE_SCE;
> + che = ff_aac_get_che(ac, TYPE_SCE, layout_id);
> + } else if (e->type == ID_USAC_CPE) {
> + layout_id = elem_id[1]++;
> + layout_type = TYPE_CPE;
> + che = ff_aac_get_che(ac, TYPE_CPE, layout_id);
> + } else if (e->type == ID_USAC_LFE) {
> + layout_id = elem_id[2]++;
> + layout_type = TYPE_LFE;
> + che = ff_aac_get_che(ac, TYPE_LFE, layout_id);
> + }
> +
> + if (e->type != ID_USAC_EXT && !che) {
> + av_log(ac->avctx, AV_LOG_ERROR,
> + "channel element %d.%d is not allocated\n",
> + layout_type, layout_id);
> + return AVERROR_INVALIDDATA;
> + }
> +
> switch (e->type) {
> case ID_USAC_LFE:
> /* Fallthrough */
> case ID_USAC_SCE:
> - che = ff_aac_get_che(ac, TYPE_SCE, nb_ch_el++);
> - if (!che) {
> - av_log(ac->avctx, AV_LOG_ERROR,
> - "channel element %d.%d is not allocated\n",
> - TYPE_SCE, nb_ch_el - 1);
> - return AVERROR_INVALIDDATA;
> - }
> -
> ret = decode_usac_core_coder(ac, &ac->oc[1].usac, e, che, gb,
> indep_flag, 1);
> if (ret < 0)
> return ret;
>
> - sce_count++;
> audio_found = 1;
> che->present = 1;
> - samples = ac->oc[1].m4ac.frame_length_short ? 768 : 1024;
> break;
> case ID_USAC_CPE:
> - che = ff_aac_get_che(ac, TYPE_CPE, nb_ch_el++);
> - if (!che) {
> - av_log(ac->avctx, AV_LOG_ERROR,
> - "channel element %d.%d is not allocated\n",
> - TYPE_CPE, nb_ch_el - 1);
> - return AVERROR_INVALIDDATA;
> - }
> -
> ret = decode_usac_core_coder(ac, &ac->oc[1].usac, e, che, gb,
> indep_flag, 2);
> if (ret < 0)
> @@ -1586,7 +1605,6 @@ int ff_aac_usac_decode_frame(AVCodecContext *avctx,
> AACDecContext *ac,
>
> audio_found = 1;
> che->present = 1;
> - samples = ac->oc[1].m4ac.frame_length_short ? 768 : 1024;
> break;
> case ID_USAC_EXT:
> ret = parse_ext_ele(ac, e, gb);
> @@ -1596,6 +1614,9 @@ int ff_aac_usac_decode_frame(AVCodecContext *avctx,
> AACDecContext *ac,
> }
> }
>
> + if (audio_found)
> + samples = ac->oc[1].m4ac.frame_length_short ? 768 : 1024;
> +
> if (ac->oc[1].status && audio_found) {
> avctx->sample_rate = ac->oc[1].m4ac.sample_rate;
> avctx->frame_size = samples;
> @@ -1619,7 +1640,7 @@ int ff_aac_usac_decode_frame(AVCodecContext *avctx,
> AACDecContext *ac,
> }
>
> /* for dual-mono audio (SCE + SCE) */
> - is_dmono = ac->dmono_mode && sce_count == 2 &&
> + is_dmono = ac->dmono_mode && elem_id[0] == 2 &&
> !av_channel_layout_compare(&ac->oc[1].ch_layout,
>
> &(AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO);
> if (is_dmono) {
> --
> 2.43.0.381.gb435a96ce8
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Do you also get (unbearable) hard-noise when seeking forward in file (both
ffplay/mpv) ?
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