From 7ae1c0dd3ef8038f541716eb283380fd196041ad Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Tue, 20 Sep 2022 14:20:07 +0200 Subject: [PATCH] avcodec/h264_redundant_pps_bsf: Don't remove PPS There is no check for whether these supposedly redundant PPS are actually redundant. One could check via memcmp which would work in practice* (because all content buffers are initially zero-allocated), but this is not portable as compilers may trash padding inside structures as they wish. In case the PPS is not really redundant the output is garbage. This happens with several files from the FATE-suite. E.g. h264-conformance/CVCANLMA2_Sony_C.jsv doesn't decode correctly any more, whereas h264-conformance/CABA3_TOSHIBA_E.264 even fails in ff_cbs_write_packet(), because the inferred value of num_ref_idx_l0_active_minus1 mismatches with the value set in the slice (this happens when num_ref_idx_l0_default_active_minus1 changes in the PPS; the value in the slice header is inferred from the original PPS's num_ref_idx_l0_default_active_minus1). *: Unless slice_group_id is used, i.e. unless slice_group_map_type is six. Signed-off-by: Andreas Rheinhardt --- doc/bitstream_filters.texi | 3 --- libavcodec/h264_redundant_pps_bsf.c | 11 ----------- 2 files changed, 14 deletions(-) diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi index 50c95f035d..c63c20370f 100644 --- a/doc/bitstream_filters.texi +++ b/doc/bitstream_filters.texi @@ -382,9 +382,6 @@ This applies a specific fixup to some Blu-ray streams which contain redundant PPSs modifying irrelevant parameters of the stream which confuse other transformations which require correct extradata. -A new single global PPS is created, and all of the redundant PPSs -within the stream are removed. - @section hevc_metadata Modify metadata embedded in an HEVC stream. diff --git a/libavcodec/h264_redundant_pps_bsf.c b/libavcodec/h264_redundant_pps_bsf.c index f8bab1f109..df9a88a705 100644 --- a/libavcodec/h264_redundant_pps_bsf.c +++ b/libavcodec/h264_redundant_pps_bsf.c @@ -80,26 +80,15 @@ static int h264_redundant_pps_update_fragment(AVBSFContext *bsf, CodedBitstreamFragment *au) { H264RedundantPPSContext *ctx = bsf->priv_data; - int au_has_sps; int err, i; - au_has_sps = 0; for (i = 0; i < au->nb_units; i++) { CodedBitstreamUnit *nal = &au->units[i]; - if (nal->type == H264_NAL_SPS) - au_has_sps = 1; if (nal->type == H264_NAL_PPS) { err = h264_redundant_pps_fixup_pps(ctx, nal); if (err < 0) return err; - if (!au_has_sps) { - av_log(bsf, AV_LOG_VERBOSE, "Deleting redundant PPS " - "at %"PRId64".\n", pkt->pts); - ff_cbs_delete_unit(au, i); - i--; - continue; - } } if (nal->type == H264_NAL_SLICE || nal->type == H264_NAL_IDR_SLICE) {