On Mon, Sep 16, 2013 at 04:02:07PM -0700, Alex Converse wrote:
> This does not add support for any error resiliance tools.
> ---
> Changelog | 1 +
> libavcodec/aacdec.c | 116
> +++++++++++++++++++++++++++++++++++++++++++++++-----
> 2 files changed, 107 insertions(+), 10 deletions(-)
>
> diff --git a/Changelog b/Changelog
> index 7e210a7..5261c18 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -33,6 +33,7 @@ version 10:
> - avconv -t option can now be used for inputs, to limit the duration of
> data read from an input file
> - incomplete Voxware MetaSound decoder
> +- Error Resiliant AAC syntax (ER AAC LC) decoding
>
>
> version 9:
> diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c
> index 62246b6..4a18946 100644
> --- a/libavcodec/aacdec.c
> +++ b/libavcodec/aacdec.c
> @@ -706,7 +706,7 @@ static int decode_ga_specific_config(AACContext *ac,
> AVCodecContext *avctx,
> MPEG4AudioConfig *m4ac,
> int channel_config)
> {
> - int extension_flag, ret;
> + int extension_flag, ret, ep_config, res_flags;
> uint8_t layout_map[MAX_ELEM_ID*4][3];
> int tags = 0;
>
> @@ -752,14 +752,30 @@ static int decode_ga_specific_config(AACContext *ac,
> AVCodecContext *avctx,
> case AOT_ER_AAC_LTP:
> case AOT_ER_AAC_SCALABLE:
> case AOT_ER_AAC_LD:
> - skip_bits(gb, 3); /* aacSectionDataResilienceFlag
> - * aacScalefactorDataResilienceFlag
> - * aacSpectralDataResilienceFlag
> - */
> + res_flags = get_bits(gb, 3);
> + if (res_flags) {
> + av_log(avctx, AV_LOG_ERROR,
> + "AAC data resiliance not supported (flags %x)\n",
> + res_flags);
> + return AVERROR_PATCHWELCOME;
> + }
> break;
> }
> skip_bits1(gb); // extensionFlag3 (TBD in version 3)
> }
> + switch (m4ac->object_type) {
> + case AOT_ER_AAC_LC:
> + case AOT_ER_AAC_LTP:
> + case AOT_ER_AAC_SCALABLE:
> + case AOT_ER_AAC_LD:
> + ep_config = get_bits(gb, 2);
> + if (ep_config) {
> + av_log(avctx, AV_LOG_ERROR,
> + "epConfig %d is not supported.\n",
> + ep_config);
> + return AVERROR_PATCHWELCOME;
> + }
> + }
> return 0;
> }
>
> @@ -808,6 +824,7 @@ static int decode_audio_specific_config(AACContext *ac,
> case AOT_AAC_MAIN:
> case AOT_AAC_LC:
> case AOT_AAC_LTP:
> + case AOT_ER_AAC_LC:
> if ((ret = decode_ga_specific_config(ac, avctx, &gb,
> m4ac, m4ac->chan_config)) < 0)
> return ret;
> @@ -1079,7 +1096,8 @@ static int decode_ics_info(AACContext *ac,
> IndividualChannelStream *ics,
> if (decode_prediction(ac, ics, gb)) {
> return AVERROR_INVALIDDATA;
> }
> - } else if (ac->oc[1].m4ac.object_type == AOT_AAC_LC) {
> + } else if (ac->oc[1].m4ac.object_type == AOT_AAC_LC ||
> + ac->oc[1].m4ac.object_type == AOT_ER_AAC_LC) {
> av_log(ac->avctx, AV_LOG_ERROR,
> "Prediction is not allowed in AAC-LC.\n");
> return AVERROR_INVALIDDATA;
> @@ -1701,7 +1719,7 @@ static int decode_ics(AACContext *ac,
> SingleChannelElement *sce,
> TemporalNoiseShaping *tns = &sce->tns;
> IndividualChannelStream *ics = &sce->ics;
> float *out = sce->coeffs;
> - int global_gain, pulse_present = 0;
> + int global_gain, er_syntax, pulse_present = 0;
> int ret;
>
> /* This assignment is to silence a GCC warning about the variable being
> used
> @@ -1724,6 +1742,9 @@ static int decode_ics(AACContext *ac,
> SingleChannelElement *sce,
> return ret;
>
> pulse_present = 0;
> + er_syntax = ac->oc[1].m4ac.object_type == AOT_ER_AAC_LC ||
> + ac->oc[1].m4ac.object_type == AOT_ER_AAC_LTP ||
> + ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD;
> if (!scale_flag) {
> if ((pulse_present = get_bits1(gb))) {
> if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
> @@ -1737,12 +1758,19 @@ static int decode_ics(AACContext *ac,
> SingleChannelElement *sce,
> return AVERROR_INVALIDDATA;
> }
> }
> - if ((tns->present = get_bits1(gb)) && decode_tns(ac, tns, gb, ics))
> - return AVERROR_INVALIDDATA;
> + tns->present = get_bits1(gb);
> + if (tns->present && !er_syntax)
> + if (decode_tns(ac, tns, gb, ics) < 0)
> + return AVERROR_INVALIDDATA;
wrong indentation
> if (get_bits1(gb)) {
> avpriv_request_sample(ac->avctx, "SSR");
> return AVERROR_PATCHWELCOME;
> }
> + // I see no textual basis in the spec for this occuring after SSR
> gain
> + // control, but this is what both reference and real implmentations
> do
> + if (tns->present && er_syntax)
> + if (decode_tns(ac, tns, gb, ics) < 0)
> + return AVERROR_INVALIDDATA;
here too
> }
>
> if (decode_spectrum_and_dequant(ac, out, gb, sce->sf, pulse_present,
> @@ -2466,6 +2494,65 @@ static int parse_adts_frame_header(AACContext *ac,
> GetBitContext *gb)
> return size;
> }
>
> +static int aac_decode_er_frame(AVCodecContext *avctx, void *data,
> + int *got_frame_ptr, GetBitContext *gb)
> +{
> + AACContext *ac = avctx->priv_data;
> + ChannelElement *che;
> + int err, i;
> + int samples = 1024;
> + int chan_config = ac->oc[1].m4ac.chan_config;
> +
> + ac->frame = data;
> +
> + if ((err = frame_configure_elements(avctx)) < 0)
> + goto fail;
> +
> + ac->tags_mapped = 0;
> +
> + if (chan_config < 0 || chan_config >= 8) {
> + avpriv_request_sample(avctx, "Unknown ER channel configuration %d",
> + ac->oc[1].m4ac.chan_config);
> + err = AVERROR_INVALIDDATA;
> + goto fail;
> + }
> + for (i = 0; i < tags_per_config[chan_config]; i++) {
> + const int elem_type = aac_channel_layout_map[chan_config-1][i][0];
> + const int elem_id = aac_channel_layout_map[chan_config-1][i][1];
> + if (!(che=get_che(ac, elem_type, elem_id))) {
> + av_log(ac->avctx, AV_LOG_ERROR,
> + "channel element %d.%d is not allocated\n",
> + elem_type, elem_id);
> + err = AVERROR_INVALIDDATA;
> + goto fail;
> + }
> + skip_bits(gb, 4);
> + switch (elem_type) {
> + case TYPE_SCE:
> + err = decode_ics(ac, &che->ch[0], gb, 0, 0);
> + break;
> + case TYPE_CPE:
> + err = decode_cpe(ac, gb, che);
> + break;
> + case TYPE_LFE:
> + err = decode_ics(ac, &che->ch[0], gb, 0, 0);
> + break;
> + }
> + if (err < 0)
> + goto fail;
> + }
> +
> + spectral_to_sample(ac);
> +
> + ac->frame->nb_samples = samples;
> + *got_frame_ptr = 1;
> +
> + skip_bits_long(gb, get_bits_left(gb));
> + return 0;
> +fail:
> + return err;
> +}
> +
> static int aac_decode_frame_int(AVCodecContext *avctx, void *data,
> int *got_frame_ptr, GetBitContext *gb)
> {
> @@ -2639,7 +2726,16 @@ static int aac_decode_frame(AVCodecContext *avctx,
> void *data,
> if ((err = init_get_bits(&gb, buf, buf_size * 8)) < 0)
> return err;
>
> - if ((err = aac_decode_frame_int(avctx, data, got_frame_ptr, &gb)) < 0)
> + switch (ac->oc[1].m4ac.object_type) {
> + case AOT_ER_AAC_LC:
> + case AOT_ER_AAC_LTP:
> + case AOT_ER_AAC_LD:
> + err = aac_decode_er_frame(avctx, data, got_frame_ptr, &gb);
> + break;
> + default:
> + err = aac_decode_frame_int(avctx, data, got_frame_ptr, &gb);
> + }
> + if (err < 0)
> return err;
>
> buf_consumed = (get_bits_count(&gb) + 7) >> 3;
> --
in general LGTM
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