Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

avcodec/evc_parse: split off deriving PoC

Browse Source 
Signed-off-by: James Almer <jamrial@gmail.com>
pull/389/head
James Almer 2 years ago
parent f7e0af5edc
commit ff7a4cdf04
2 changed files with 79 additions and 68 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 142
      libavcodec/evc_parse.c
  2. 5
      libavcodec/evc_parse.h

142
libavcodec/evc_parse.c
Unescape View File

@ -187,6 +187,77 @@ static int evc_parse_slice_header(EVCParserContext *ctx, EVCParserSliceHeader *s
return 0;
}
int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh,
EVCParserPoc *poc, enum EVCNALUnitType nalu_type, int tid)
{
const EVCParserPPS *pps = ps->pps[sh->slice_pic_parameter_set_id];
const EVCParserSPS *sps;
if (!pps)
return AVERROR_INVALIDDATA;
sps = ps->sps[pps->pps_seq_parameter_set_id];
if (!sps)
return AVERROR_INVALIDDATA;
if (sps->sps_pocs_flag) {
int PicOrderCntMsb = 0;
poc->prevPicOrderCntVal = poc->PicOrderCntVal;
if (nalu_type == EVC_IDR_NUT)
PicOrderCntMsb = 0;
else {
int MaxPicOrderCntLsb = 1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4);
int prevPicOrderCntLsb = poc->PicOrderCntVal & (MaxPicOrderCntLsb - 1);
int prevPicOrderCntMsb = poc->PicOrderCntVal - prevPicOrderCntLsb;
if ((sh->slice_pic_order_cnt_lsb < prevPicOrderCntLsb) &&
((prevPicOrderCntLsb - sh->slice_pic_order_cnt_lsb) >= (MaxPicOrderCntLsb / 2)))
PicOrderCntMsb = prevPicOrderCntMsb + MaxPicOrderCntLsb;
else if ((sh->slice_pic_order_cnt_lsb > prevPicOrderCntLsb) &&
((sh->slice_pic_order_cnt_lsb - prevPicOrderCntLsb) > (MaxPicOrderCntLsb / 2)))
PicOrderCntMsb = prevPicOrderCntMsb - MaxPicOrderCntLsb;
else
PicOrderCntMsb = prevPicOrderCntMsb;
}
poc->PicOrderCntVal = PicOrderCntMsb + sh->slice_pic_order_cnt_lsb;
} else {
if (nalu_type == EVC_IDR_NUT) {
poc->PicOrderCntVal = 0;
poc->DocOffset = -1;
} else {
int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length);
if (tid == 0) {
poc->PicOrderCntVal = poc->prevPicOrderCntVal + SubGopLength;
poc->DocOffset = 0;
poc->prevPicOrderCntVal = poc->PicOrderCntVal;
} else {
int ExpectedTemporalId;
int PocOffset;
int prevDocOffset = poc->DocOffset;
poc->DocOffset = (prevDocOffset + 1) % SubGopLength;
if (poc->DocOffset == 0) {
poc->prevPicOrderCntVal += SubGopLength;
ExpectedTemporalId = 0;
} else
ExpectedTemporalId = 1 + (int)log2(poc->DocOffset);
while (tid != ExpectedTemporalId) {
poc->DocOffset = (poc->DocOffset + 1) % SubGopLength;
if (poc->DocOffset == 0)
ExpectedTemporalId = 0;
else
ExpectedTemporalId = 1 + (int)log2(poc->DocOffset);
}
PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / (int)pow(2.0, tid) - 2));
poc->PicOrderCntVal = poc->prevPicOrderCntVal + PocOffset;
}
}
}
return 0;
}
int ff_evc_parse_nal_unit(EVCParserContext *ctx, const uint8_t *buf, int buf_size, void *logctx)
{
int nalu_type, nalu_size;
@ -299,8 +370,6 @@ int ff_evc_parse_nal_unit(EVCParserContext *ctx, const uint8_t *buf, int buf_siz
case EVC_IDR_NUT: // Coded slice of a IDR or non-IDR picture
case EVC_NOIDR_NUT: {
EVCParserSliceHeader sh;
const EVCParserSPS *sps;
const EVCParserPPS *pps;
int ret;
ret = evc_parse_slice_header(ctx, &sh, data, nalu_size);
@ -331,72 +400,9 @@ int ff_evc_parse_nal_unit(EVCParserContext *ctx, const uint8_t *buf, int buf_siz
// 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
pps = ctx->ps.pps[sh.slice_pic_parameter_set_id];
sps = ctx->ps.sps[pps->pps_seq_parameter_set_id];
av_assert0(sps && pps);
if (sps->sps_pocs_flag) {
int PicOrderCntMsb = 0;
ctx->poc.prevPicOrderCntVal = ctx->poc.PicOrderCntVal;
if (nalu_type == EVC_IDR_NUT)
PicOrderCntMsb = 0;
else {
int MaxPicOrderCntLsb = 1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4);
int prevPicOrderCntLsb = ctx->poc.PicOrderCntVal & (MaxPicOrderCntLsb - 1);
int prevPicOrderCntMsb = ctx->poc.PicOrderCntVal - prevPicOrderCntLsb;
if ((sh.slice_pic_order_cnt_lsb < prevPicOrderCntLsb) &&
((prevPicOrderCntLsb - sh.slice_pic_order_cnt_lsb) >= (MaxPicOrderCntLsb / 2)))
PicOrderCntMsb = prevPicOrderCntMsb + MaxPicOrderCntLsb;
else if ((sh.slice_pic_order_cnt_lsb > prevPicOrderCntLsb) &&
((sh.slice_pic_order_cnt_lsb - prevPicOrderCntLsb) > (MaxPicOrderCntLsb / 2)))
PicOrderCntMsb = prevPicOrderCntMsb - MaxPicOrderCntLsb;
else
PicOrderCntMsb = prevPicOrderCntMsb;
}
ctx->poc.PicOrderCntVal = PicOrderCntMsb + sh.slice_pic_order_cnt_lsb;
} else {
if (nalu_type == EVC_IDR_NUT) {
ctx->poc.PicOrderCntVal = 0;
ctx->poc.DocOffset = -1;
} else {
int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length);
if (tid == 0) {
ctx->poc.PicOrderCntVal = ctx->poc.prevPicOrderCntVal + SubGopLength;
ctx->poc.DocOffset = 0;
ctx->poc.prevPicOrderCntVal = ctx->poc.PicOrderCntVal;
} else {
int ExpectedTemporalId;
int PocOffset;
int prevDocOffset = ctx->poc.DocOffset;
ctx->poc.DocOffset = (prevDocOffset + 1) % SubGopLength;
if (ctx->poc.DocOffset == 0) {
ctx->poc.prevPicOrderCntVal += SubGopLength;
ExpectedTemporalId = 0;
} else
ExpectedTemporalId = 1 + (int)log2(ctx->poc.DocOffset);
while (tid != ExpectedTemporalId) {
ctx->poc.DocOffset = (ctx->poc.DocOffset + 1) % SubGopLength;
if (ctx->poc.DocOffset == 0)
ExpectedTemporalId = 0;
else
ExpectedTemporalId = 1 + (int)log2(ctx->poc.DocOffset);
}
PocOffset = (int)(SubGopLength * ((2.0 * ctx->poc.DocOffset + 1) / (int)pow(2.0, tid) - 2));
ctx->poc.PicOrderCntVal = ctx->poc.prevPicOrderCntVal + PocOffset;
}
}
}
ret = ff_evc_derive_poc(&ctx->ps, &sh, &ctx->poc, nalu_type, tid);
if (ret < 0)
return ret;
ctx->output_picture_number = ctx->poc.PicOrderCntVal;
ctx->key_frame = (nalu_type == EVC_IDR_NUT) ? 1 : 0;

5
libavcodec/evc_parse.h
Unescape View File

@ -159,4 +159,9 @@ int ff_evc_get_temporal_id(const uint8_t *bits, int bits_size, void *logctx);
int ff_evc_parse_nal_unit(EVCParserContext *ctx, const uint8_t *buf, int buf_size, void *logctx);
// 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
int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh,
EVCParserPoc *poc, enum EVCNALUnitType nalu_type, int tid);
#endif /* AVCODEC_EVC_PARSE_H */

Write Preview
Loading…
Cancel
Save