ffmpeg | branch: master | Mark Thompson <s...@jkqxz.net> | Mon Sep 25 12:44:58 2023 +0100| [014c13863327519418ca8bd15d21c4e8a58d9227] | committer: Mark Thompson
cbs_av1: Make fake OBU size length field a write option This is an option to modify the behaviour of the writer, not a syntax field. > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=014c13863327519418ca8bd15d21c4e8a58d9227 --- libavcodec/cbs_av1.c | 31 +++++++++++++++++++++---------- libavcodec/cbs_av1.h | 5 ++++- libavcodec/vaapi_encode_av1.c | 4 +++- 3 files changed, 28 insertions(+), 12 deletions(-) diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c index 4e687ace79..ed9a7b80d4 100644 --- a/libavcodec/cbs_av1.c +++ b/libavcodec/cbs_av1.c @@ -138,19 +138,25 @@ static int cbs_av1_read_leb128(CodedBitstreamContext *ctx, GetBitContext *gbc, return 0; } -/** Minimum byte length will be used to indicate the len128 of value if byte_len is 0. */ static int cbs_av1_write_leb128(CodedBitstreamContext *ctx, PutBitContext *pbc, - const char *name, uint64_t value, uint8_t byte_len) + const char *name, uint64_t value, int fixed_length) { int len, i; uint8_t byte; CBS_TRACE_WRITE_START(); - if (byte_len) - av_assert0(byte_len >= (av_log2(value) + 7) / 7); + len = (av_log2(value) + 7) / 7; - len = byte_len ? byte_len : (av_log2(value) + 7) / 7; + if (fixed_length) { + if (fixed_length < len) { + av_log(ctx->log_ctx, AV_LOG_ERROR, "OBU is too large for " + "fixed length size field (%d > %d).\n", + len, fixed_length); + return AVERROR(EINVAL); + } + len = fixed_length; + } for (i = 0; i < len; i++) { if (put_bits_left(pbc) < 8) @@ -1006,8 +1012,8 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx, if (obu->header.obu_has_size_field) { pbc_tmp = *pbc; - if (obu->obu_size_byte_len) { - for (int i = 0; i < obu->obu_size_byte_len; i++) + if (priv->fixed_obu_size_length) { + for (int i = 0; i < priv->fixed_obu_size_length; i++) put_bits(pbc, 8, 0); } else { // Add space for the size field to fill later. @@ -1133,7 +1139,8 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx, end_pos /= 8; *pbc = pbc_tmp; - err = cbs_av1_write_leb128(ctx, pbc, "obu_size", obu->obu_size, obu->obu_size_byte_len); + err = cbs_av1_write_leb128(ctx, pbc, "obu_size", obu->obu_size, + priv->fixed_obu_size_length); if (err < 0) goto error; @@ -1150,10 +1157,12 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx, } if (obu->obu_size > 0) { - if (!obu->obu_size_byte_len) { - obu->obu_size_byte_len = start_pos - data_pos; + if (!priv->fixed_obu_size_length) { memmove(pbc->buf + data_pos, pbc->buf + start_pos, header_size); + } else { + // The size was fixed so the following data was + // already written in the correct place. } skip_put_bytes(pbc, header_size); @@ -1273,6 +1282,8 @@ static const CodedBitstreamUnitTypeDescriptor cbs_av1_unit_types[] = { static const AVOption cbs_av1_options[] = { { "operating_point", "Set operating point to select layers to parse from a scalable bitstream", OFFSET(operating_point), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, AV1_MAX_OPERATING_POINTS - 1, 0 }, + { "fixed_obu_size_length", "Set fixed length of the obu_size field", + OFFSET(fixed_obu_size_length), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 8, 0 }, { NULL } }; diff --git a/libavcodec/cbs_av1.h b/libavcodec/cbs_av1.h index a9e2d2284f..7924257164 100644 --- a/libavcodec/cbs_av1.h +++ b/libavcodec/cbs_av1.h @@ -401,7 +401,6 @@ typedef struct AV1RawOBU { AV1RawOBUHeader header; size_t obu_size; - uint8_t obu_size_byte_len; union { AV1RawSequenceHeader sequence_header; @@ -468,6 +467,10 @@ typedef struct CodedBitstreamAV1Context { // AVOptions int operating_point; + // When writing, fix the length in bytes of the obu_size field. + // Writing will fail with an error if an OBU larger than can be + // represented by the fixed size is encountered. + int fixed_obu_size_length; } CodedBitstreamAV1Context; diff --git a/libavcodec/vaapi_encode_av1.c b/libavcodec/vaapi_encode_av1.c index 3ff1c47b53..5a9ff0f798 100644 --- a/libavcodec/vaapi_encode_av1.c +++ b/libavcodec/vaapi_encode_av1.c @@ -634,7 +634,6 @@ static int vaapi_encode_av1_init_picture_params(AVCodecContext *avctx, } } - fh_obu->obu_size_byte_len = priv->attr_ext2.bits.obu_size_bytes_minus1 + 1; ret = vaapi_encode_av1_add_obu(avctx, obu, AV1_OBU_FRAME_HEADER, &priv->fh); if (ret < 0) goto end; @@ -839,6 +838,9 @@ static av_cold int vaapi_encode_av1_init(AVCodecContext *avctx) priv->attr_ext2.value = attr.value; } + av_opt_set_int(priv->cbc->priv_data, "fixed_obu_size_length", + priv->attr_ext2.bits.obu_size_bytes_minus1 + 1, 0); + ret = vaapi_encode_av1_set_tile(avctx); if (ret < 0) return ret; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
