[FFmpeg-devel] [PATCH 1/3] avcodec/evc_frame_merge: properly support packets with more than one NALU
James Almer
jamrial at gmail.com
Wed Jun 21 19:59:47 EEST 2023
Parse through all NALUs in a packet, pull new ones when a complete AU could not
be assembled, or keep them around if an AU was assembled while data remained in
them.
Signed-off-by: James Almer <jamrial at gmail.com>
---
libavcodec/evc_frame_merge_bsf.c | 110 +++++++++++++++++++------------
1 file changed, 69 insertions(+), 41 deletions(-)
diff --git a/libavcodec/evc_frame_merge_bsf.c b/libavcodec/evc_frame_merge_bsf.c
index a9b44f4d10..8af6095bf1 100644
--- a/libavcodec/evc_frame_merge_bsf.c
+++ b/libavcodec/evc_frame_merge_bsf.c
@@ -70,30 +70,14 @@ static void evc_frame_merge_flush(AVBSFContext *bsf)
ctx->au_buffer.data_size = 0;
}
-static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
+static int parse_nal_unit(AVBSFContext *bsf, const uint8_t *buf, int buf_size)
{
EVCFMergeContext *ctx = bsf->priv_data;
- AVPacket *in = ctx->in;
- uint8_t *buffer;
GetBitContext gb;
enum EVCNALUnitType nalu_type;
- uint32_t nalu_size;
- int tid, au_end_found = 0;
- int err;
-
- err = ff_bsf_get_packet_ref(bsf, in);
- if (err < 0)
- return err;
-
- // NAL unit parsing needed to determine if end of AU was found
- nalu_size = evc_read_nal_unit_length(in->data, EVC_NALU_LENGTH_PREFIX_SIZE, bsf);
- if (!nalu_size || nalu_size > INT_MAX) {
- av_log(bsf, AV_LOG_ERROR, "Invalid NAL unit size: (%d)\n", nalu_size);
- err = AVERROR_INVALIDDATA;
- goto end;
- }
+ int tid, err;
- err = init_get_bits8(&gb, in->data + EVC_NALU_LENGTH_PREFIX_SIZE, nalu_size);
+ err = init_get_bits8(&gb, buf, buf_size);
if (err < 0)
return err;
@@ -101,15 +85,13 @@ static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
// @see enum EVCNALUnitType in evc.h
if (get_bits1(&gb)) {// forbidden_zero_bit
av_log(bsf, AV_LOG_ERROR, "Invalid NAL unit header\n");
- err = AVERROR_INVALIDDATA;
- goto end;
+ return AVERROR_INVALIDDATA;
}
nalu_type = get_bits(&gb, 6) - 1;
if (nalu_type < EVC_NOIDR_NUT || nalu_type > EVC_UNSPEC_NUT62) {
av_log(bsf, AV_LOG_ERROR, "Invalid NAL unit type: (%d)\n", nalu_type);
- err = AVERROR_INVALIDDATA;
- goto end;
+ return AVERROR_INVALIDDATA;
}
tid = get_bits(&gb, 3);
@@ -121,14 +103,14 @@ static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
err = ff_evc_parse_sps(&gb, &ctx->ps);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "SPS parsing error\n");
- goto end;
+ return err;
}
break;
case EVC_PPS_NUT:
err = ff_evc_parse_pps(&gb, &ctx->ps);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "PPS parsing error\n");
- goto end;
+ return err;
}
break;
case EVC_IDR_NUT: // Coded slice of a IDR or non-IDR picture
@@ -138,16 +120,16 @@ static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
err = ff_evc_parse_slice_header(&gb, &sh, &ctx->ps, nalu_type);
if (err < 0) {
av_log(bsf, AV_LOG_ERROR, "Slice header parsing error\n");
- goto end;
+ return err;
}
// POC (picture order count of the current picture) derivation
// @see ISO/IEC 23094-1:2020(E) 8.3.1 Decoding process for picture order count
err = ff_evc_derive_poc(&ctx->ps, &sh, &ctx->poc, nalu_type, tid);
if (err < 0)
- goto end;
+ return err;
- au_end_found = end_of_access_unit_found(&ctx->ps, &sh, &ctx->poc, nalu_type);
+ return end_of_access_unit_found(&ctx->ps, &sh, &ctx->poc, nalu_type);
break;
}
@@ -158,8 +140,56 @@ static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
break;
}
+ return 0;
+}
+
+static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
+{
+ EVCFMergeContext *ctx = bsf->priv_data;
+ AVPacket *in = ctx->in;
+ size_t data_size;
+ int au_end_found = 0, err;
+
+ while (!au_end_found) {
+ uint8_t *buffer;
+ uint32_t nalu_size;
+
+ if (!in->size) {
+ av_packet_unref(in);
+ err = ff_bsf_get_packet_ref(bsf, in);
+ if (err < 0) {
+ if (err == AVERROR_EOF && ctx->au_buffer.data_size > 0)
+ break;
+ return err;
+ }
+ }
+
+ // Buffer size is not enough for buffer to store NAL unit 4-bytes prefix (length)
+ if (in->size < EVC_NALU_LENGTH_PREFIX_SIZE)
+ return AVERROR_INVALIDDATA;
+
+ nalu_size = evc_read_nal_unit_length(in->data, EVC_NALU_LENGTH_PREFIX_SIZE, bsf);
+ if (!nalu_size || nalu_size > INT_MAX) {
+ av_log(bsf, AV_LOG_ERROR, "Invalid NAL unit size: (%u)\n", nalu_size);
+ err = AVERROR_INVALIDDATA;
+ goto end;
+ }
+
+ if (in->size < nalu_size + EVC_NALU_LENGTH_PREFIX_SIZE) {
+ err = AVERROR_INVALIDDATA;
+ goto end;
+ }
+
+ err = parse_nal_unit(bsf, in->data + EVC_NALU_LENGTH_PREFIX_SIZE, nalu_size);
+ if (err < 0) {
+ av_log(bsf, AV_LOG_ERROR, "Parsing of NAL unit failed\n");
+ goto end;
+ }
+ au_end_found = err;
+
+ nalu_size += EVC_NALU_LENGTH_PREFIX_SIZE;
buffer = av_fast_realloc(ctx->au_buffer.data, &ctx->au_buffer.capacity,
- ctx->au_buffer.data_size + in->size);
+ ctx->au_buffer.data_size + nalu_size);
if (!buffer) {
av_freep(&ctx->au_buffer.data);
err = AVERROR_INVALIDDATA;
@@ -167,30 +197,28 @@ static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
}
ctx->au_buffer.data = buffer;
- memcpy(ctx->au_buffer.data + ctx->au_buffer.data_size, in->data, in->size);
+ memcpy(ctx->au_buffer.data + ctx->au_buffer.data_size, in->data, nalu_size);
- ctx->au_buffer.data_size += in->size;
+ ctx->au_buffer.data_size += nalu_size;
- av_packet_unref(in);
+ in->data += nalu_size;
+ in->size -= nalu_size;
+ }
- if (au_end_found) {
- size_t data_size = ctx->au_buffer.data_size;
+ av_packet_unref(in);
+ data_size = ctx->au_buffer.data_size;
ctx->au_buffer.data_size = 0;
err = av_new_packet(out, data_size);
if (err < 0)
- return err;
+ goto end;
memcpy(out->data, ctx->au_buffer.data, data_size);
- } else
- err = AVERROR(EAGAIN);
-
- if (err < 0 && err != AVERROR(EAGAIN))
- ctx->au_buffer.data_size = 0;
+ err = 0;
end:
if (err < 0)
- av_packet_unref(in);
+ evc_frame_merge_flush(bsf);
return err;
}
--
2.41.0
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