| Message ID | 20200810093432.24454-3-guangxin.xu@intel.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | avformat/av1dec: add low overhead obu demux | expand |
| Context | Check | Description |
|---|---|---|
| andriy/default | pending | |
| andriy/make | success | Make finished |
| andriy/make_fate | success | Make fate finished |
On 8/10/2020 6:34 AM, Xu Guangxin wrote: > It's defined in Section 5.2, used by netflix. > see http://download.opencontent.netflix.com/?prefix=AV1/Chimera/ > --- > configure | 1 + > libavformat/allformats.c | 1 + > libavformat/av1dec.c | 266 +++++++++++++++++++++++++++++++++++---- > 3 files changed, 245 insertions(+), 23 deletions(-) > > diff --git a/configure b/configure > index 8de1afcb99..d4a1fea9ce 100755 > --- a/configure > +++ b/configure > @@ -3331,6 +3331,7 @@ mxf_d10_muxer_select="mxf_muxer" > mxf_opatom_muxer_select="mxf_muxer" > nut_muxer_select="riffenc" > nuv_demuxer_select="riffdec" > +obu_demuxer_select="av1_frame_merge_bsf av1_parser" > oga_muxer_select="ogg_muxer" > ogg_demuxer_select="dirac_parse" > ogv_muxer_select="ogg_muxer" > diff --git a/libavformat/allformats.c b/libavformat/allformats.c > index b7e59ae170..0aa9dd7198 100644 > --- a/libavformat/allformats.c > +++ b/libavformat/allformats.c > @@ -293,6 +293,7 @@ extern AVOutputFormat ff_null_muxer; > extern AVInputFormat ff_nut_demuxer; > extern AVOutputFormat ff_nut_muxer; > extern AVInputFormat ff_nuv_demuxer; > +extern AVInputFormat ff_obu_demuxer; > extern AVOutputFormat ff_oga_muxer; > extern AVInputFormat ff_ogg_demuxer; > extern AVOutputFormat ff_ogg_muxer; > diff --git a/libavformat/av1dec.c b/libavformat/av1dec.c > index 1be2fac1c1..14efb8f1d4 100644 > --- a/libavformat/av1dec.c > +++ b/libavformat/av1dec.c > @@ -70,6 +70,24 @@ static int read_obu(const uint8_t *buf, int size, int64_t *obu_size, int *type) > return 0; > } > > +//return < 0 if we need more data > +static int get_score(int type, int *seq) > +{ > + switch (type) { > + case AV1_OBU_SEQUENCE_HEADER: > + *seq = 1; > + return -1; > + case AV1_OBU_FRAME: > + case AV1_OBU_FRAME_HEADER: > + return *seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; > + case AV1_OBU_METADATA: > + return -1; > + default: > + break; Padding OBU should be ignored/skipped, same as Metadata. This function should make the caller abort only for OBUs that are not meant to appear before a Frame/Frame Header (Tile list, Tile Group, Redundant Frame Header, another Temporal Delimiter). > + } > + return 0; > +} > + > static int annexb_probe(const AVProbeData *p) > { > AVIOContext pb; > @@ -123,19 +141,9 @@ static int annexb_probe(const AVProbeData *p) > return 0; > cnt += obu_unit_size; > > - switch (type) { > - case AV1_OBU_SEQUENCE_HEADER: > - seq = 1; > - break; > - case AV1_OBU_FRAME: > - case AV1_OBU_FRAME_HEADER: > - return seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; > - case AV1_OBU_TILE_GROUP: > - case AV1_OBU_TEMPORAL_DELIMITER: > - return 0; > - default: > - break; > - } > + ret = get_score(type, &seq); > + if (ret >= 0) > + return ret; > > temporal_unit_size -= obu_unit_size + ret; > frame_unit_size -= obu_unit_size + ret; > @@ -144,15 +152,14 @@ static int annexb_probe(const AVProbeData *p) > return 0; > } > > -static int annexb_read_header(AVFormatContext *s) > +static int read_header(AVFormatContext *s, AVRational framerate, AVBSFContext **bsf, void *logctx) Nit: Maybe a pointer to framerate instead. > { > - AnnexBContext *c = s->priv_data; > const AVBitStreamFilter *filter = av_bsf_get_by_name("av1_frame_merge"); > AVStream *st; > int ret; > > if (!filter) { > - av_log(c, AV_LOG_ERROR, "av1_frame_merge bitstream filter " > + av_log(logctx, AV_LOG_ERROR, "av1_frame_merge bitstream filter " > "not found. This is a bug, please report it.\n"); > return AVERROR_BUG; > } > @@ -165,25 +172,32 @@ static int annexb_read_header(AVFormatContext *s) > st->codecpar->codec_id = AV_CODEC_ID_AV1; > st->need_parsing = AVSTREAM_PARSE_HEADERS; > > - st->internal->avctx->framerate = c->framerate; > + st->internal->avctx->framerate = framerate; > // taken from rawvideo demuxers > avpriv_set_pts_info(st, 64, 1, 1200000); > > - ret = av_bsf_alloc(filter, &c->bsf); > + ret = av_bsf_alloc(filter, bsf); > if (ret < 0) > return ret; > > - ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar); > + ret = avcodec_parameters_copy((*bsf)->par_in, st->codecpar); > if (ret < 0) { > - av_bsf_free(&c->bsf); > + av_bsf_free(bsf); > return ret; > } > > - ret = av_bsf_init(c->bsf); > + ret = av_bsf_init(*bsf); > if (ret < 0) > - av_bsf_free(&c->bsf); > + av_bsf_free(bsf); > > return ret; > + > +} > + > +static int annexb_read_header(AVFormatContext *s) > +{ > + AnnexBContext *c = s->priv_data; > + return read_header(s, c->framerate, &c->bsf, c); > } > > static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt) > @@ -251,12 +265,198 @@ static int annexb_read_close(AVFormatContext *s) > return 0; > } > > -#define OFFSET(x) offsetof(AnnexBContext, x) > +typedef struct ObuContext { > + const AVClass *class; > + AVBSFContext *bsf; > + AVRational framerate; > + uint8_t prefetched[MAX_OBU_HEADER_SIZE]; > + //prefetched len > + int len; > +} ObuContext; > + > +//For low overhead obu, we can't foresee the obu size before we parsed the header. > +//So, we can't use parse_obu_header here, since it will check size <= buf_size > +//see c27c7b49dc for more details > +static int read_obu_with_size(const uint8_t *buf, int buf_size, int64_t *obu_size, int *type) > +{ > + GetBitContext gb; > + int ret, extension_flag, start_pos; > + int64_t size; > + > + ret = init_get_bits8(&gb, buf, FFMIN(buf_size, MAX_OBU_HEADER_SIZE)); > + if (ret < 0) > + return ret; > + > + if (get_bits1(&gb) != 0) // obu_forbidden_bit > + return AVERROR_INVALIDDATA; > + > + *type = get_bits(&gb, 4); > + extension_flag = get_bits1(&gb); > + if (!get_bits1(&gb)) // has_size_flag > + return AVERROR_INVALIDDATA; > + skip_bits1(&gb); // obu_reserved_1bit > + > + if (extension_flag) { > + get_bits(&gb, 3); // temporal_id > + get_bits(&gb, 2); // spatial_id > + skip_bits(&gb, 3); // extension_header_reserved_3bits > + } > + > + *obu_size = leb128(&gb); > + if (*obu_size > INT_MAX) > + return AVERROR_INVALIDDATA; > + > + if (get_bits_left(&gb) < 0) > + return AVERROR_INVALIDDATA; > + > + start_pos = get_bits_count(&gb) / 8; > + > + size = *obu_size + start_pos; > + if (size > INT_MAX) > + return AVERROR_INVALIDDATA; > + return size; > +} > + > +static int obu_probe(const AVProbeData *p) > +{ > + int64_t obu_size; > + int seq = 0; > + int ret, type, cnt; > + > + // Check that the first OBU is a Temporal Delimiter. > + cnt = read_obu_with_size(p->buf, p->buf_size, &obu_size, &type); > + if (cnt < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size != 0) > + return 0; > + > + while (1) { > + ret = read_obu_with_size(p->buf + cnt, p->buf_size - cnt, &obu_size, &type); You need to ensure p->buf_size is bigger than cnt to avoid overreads when you attempt to skip to the next OBU, so use read_obu() here since you're passing the entire buffer length and not just up to 10 bytes like in obu_get_packet() below. The size <= buf_size check is needed here. > + if (ret < 0 || obu_size <= 0) > + return 0; > + cnt += ret; > + > + ret = get_score(type, &seq); > + if (ret >= 0) > + return ret; > + } > + return 0; > +} > + > +static int obu_read_header(AVFormatContext *s) > +{ > + ObuContext *c = s->priv_data; > + return read_header(s, c->framerate, &c->bsf, c); > +} > + > +static int obu_prefetch(AVFormatContext *s) > +{ > + ObuContext *c = s->priv_data; > + int ret; > + int size = MAX_OBU_HEADER_SIZE - c->len; > + if (size > 0 && !avio_feof(s->pb)) { > + ret = avio_read(s->pb, &c->prefetched[c->len], size); > + if (ret < 0) > + return ret; > + c->len += ret; > + } > + return c->len; > +} > + > +static int obu_read_data(AVFormatContext *s, AVPacket *pkt, int size) > +{ > + int left; > + ObuContext *c = s->priv_data; > + int ret = av_new_packet(pkt, size); > + if (ret < 0) { > + av_log(c, AV_LOG_ERROR, "Failed to allocate packet for obu\n"); > + return ret; > + } > + if (size <= c->len) { > + memcpy(pkt->data, c->prefetched, size); > + > + left = c->len - size; > + memmove(c->prefetched, c->prefetched + size, left); You can probably use av_fifo_* functions for the prefetch buffer. See libavutil/fifo.h > + c->len = left; > + } else { > + memcpy(pkt->data, c->prefetched, c->len); > + left = size - c->len; > + ret = avio_read(s->pb, pkt->data + c->len, left); > + if (ret != left) { > + av_log(c, AV_LOG_ERROR, "Failed to read %d frome file\n", left); > + return ret; > + } > + c->len = 0; > + } > + return 0; > +} > + > +static int obu_get_packet(AVFormatContext *s, AVPacket *pkt) > +{ > + int64_t obu_size; > + int ret, type; > + ObuContext *c = s->priv_data; > + ret = obu_prefetch(s); > + if (ret < 0) > + return ret; > + if (ret) { > + ret = read_obu_with_size(c->prefetched, c->len, &obu_size, &type); > + if (ret < 0) { > + av_log(c, AV_LOG_ERROR, "Failed to read obu\n"); > + return ret; > + } > + ret = obu_read_data(s, pkt, ret); > + } > + return ret; > +} > + > +static int obu_read_packet(AVFormatContext *s, AVPacket *pkt) > +{ > + ObuContext *c = s->priv_data; > + int ret; > + > + while (1) { > + ret = obu_get_packet(s, pkt); > + if (ret < 0) > + return ret; > + ret = av_bsf_send_packet(c->bsf, pkt); > + if (ret < 0) { > + av_log(s, AV_LOG_ERROR, "Failed to send packet to " > + "av1_frame_merge filter\n"); > + return ret; > + } > + ret = av_bsf_receive_packet(c->bsf, pkt); > + if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF) > + av_log(s, AV_LOG_ERROR, "av1_frame_merge filter failed to " > + "send output packet\n"); > + if (ret != AVERROR(EAGAIN)) > + break; > + } > + > + return ret; > +} > + > +static int obu_read_close(AVFormatContext *s) > +{ > + ObuContext *c = s->priv_data; > + > + av_bsf_free(&c->bsf); > + return 0; > +} > + > #define DEC AV_OPT_FLAG_DECODING_PARAM > + > +#define OFFSET(x) offsetof(AnnexBContext, x) > static const AVOption annexb_options[] = { > { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC}, > { NULL }, > }; > +#undef OFFSET > + > +#define OFFSET(x) offsetof(ObuContext, x) > +static const AVOption obu_options[] = { > + { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC}, > + { NULL }, > +}; > +#undef OFFSET > > static const AVClass annexb_demuxer_class = { > .class_name = "AV1 Annex B demuxer", > @@ -277,3 +477,23 @@ AVInputFormat ff_av1_demuxer = { > .flags = AVFMT_GENERIC_INDEX, > .priv_class = &annexb_demuxer_class, > }; > + > +static const AVClass obu_demuxer_class = { > + .class_name = "AV1 low overhead OBU demuxer", > + .item_name = av_default_item_name, > + .option = obu_options, > + .version = LIBAVUTIL_VERSION_INT, > +}; > + > +AVInputFormat ff_obu_demuxer = { > + .name = "obu", > + .long_name = NULL_IF_CONFIG_SMALL("AV1 low overhead OBU"), > + .priv_data_size = sizeof(ObuContext), > + .read_probe = obu_probe, > + .read_header = obu_read_header, > + .read_packet = obu_read_packet, > + .read_close = obu_read_close, > + .extensions = "obu", > + .flags = AVFMT_GENERIC_INDEX, > + .priv_class = &obu_demuxer_class, > +}; >
Hi James, Thanks for the review. Comment in line. > -----Original Message----- > From: ffmpeg-devel <ffmpeg-devel-bounces@ffmpeg.org> On Behalf Of James > Almer > Sent: Wednesday, August 12, 2020 9:06 PM > To: ffmpeg-devel@ffmpeg.org > Subject: Re: [FFmpeg-devel] [PATCH V2 2/3] avormat/av1dec: add low- > overhead bitstream format > > On 8/10/2020 6:34 AM, Xu Guangxin wrote: > > It's defined in Section 5.2, used by netflix. > > see http://download.opencontent.netflix.com/?prefix=AV1/Chimera/ > > --- > > configure | 1 + > > libavformat/allformats.c | 1 + > > libavformat/av1dec.c | 266 +++++++++++++++++++++++++++++++++++-- > -- > > 3 files changed, 245 insertions(+), 23 deletions(-) > > > > diff --git a/configure b/configure > > index 8de1afcb99..d4a1fea9ce 100755 > > --- a/configure > > +++ b/configure > > @@ -3331,6 +3331,7 @@ mxf_d10_muxer_select="mxf_muxer" > > mxf_opatom_muxer_select="mxf_muxer" > > nut_muxer_select="riffenc" > > nuv_demuxer_select="riffdec" > > +obu_demuxer_select="av1_frame_merge_bsf av1_parser" > > oga_muxer_select="ogg_muxer" > > ogg_demuxer_select="dirac_parse" > > ogv_muxer_select="ogg_muxer" > > diff --git a/libavformat/allformats.c b/libavformat/allformats.c index > > b7e59ae170..0aa9dd7198 100644 > > --- a/libavformat/allformats.c > > +++ b/libavformat/allformats.c > > @@ -293,6 +293,7 @@ extern AVOutputFormat ff_null_muxer; extern > > AVInputFormat ff_nut_demuxer; extern AVOutputFormat ff_nut_muxer; > > extern AVInputFormat ff_nuv_demuxer; > > +extern AVInputFormat ff_obu_demuxer; > > extern AVOutputFormat ff_oga_muxer; > > extern AVInputFormat ff_ogg_demuxer; extern AVOutputFormat > > ff_ogg_muxer; diff --git a/libavformat/av1dec.c b/libavformat/av1dec.c > > index 1be2fac1c1..14efb8f1d4 100644 > > --- a/libavformat/av1dec.c > > +++ b/libavformat/av1dec.c > > @@ -70,6 +70,24 @@ static int read_obu(const uint8_t *buf, int size, int64_t > *obu_size, int *type) > > return 0; > > } > > > > +//return < 0 if we need more data > > +static int get_score(int type, int *seq) { > > + switch (type) { > > + case AV1_OBU_SEQUENCE_HEADER: > > + *seq = 1; > > + return -1; > > + case AV1_OBU_FRAME: > > + case AV1_OBU_FRAME_HEADER: > > + return *seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; > > + case AV1_OBU_METADATA: > > + return -1; > > + default: > > + break; > > Padding OBU should be ignored/skipped, same as Metadata. This function > should make the caller abort only for OBUs that are not meant to appear before > a Frame/Frame Header (Tile list, Tile Group, Redundant Frame Header, another > Temporal Delimiter). Sure, I will add padding to allow list. > > > + } > > + return 0; > > +} > > + > > static int annexb_probe(const AVProbeData *p) { > > AVIOContext pb; > > @@ -123,19 +141,9 @@ static int annexb_probe(const AVProbeData *p) > > return 0; > > cnt += obu_unit_size; > > > > - switch (type) { > > - case AV1_OBU_SEQUENCE_HEADER: > > - seq = 1; > > - break; > > - case AV1_OBU_FRAME: > > - case AV1_OBU_FRAME_HEADER: > > - return seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; > > - case AV1_OBU_TILE_GROUP: > > - case AV1_OBU_TEMPORAL_DELIMITER: > > - return 0; > > - default: > > - break; > > - } > > + ret = get_score(type, &seq); > > + if (ret >= 0) > > + return ret; > > > > temporal_unit_size -= obu_unit_size + ret; > > frame_unit_size -= obu_unit_size + ret; @@ -144,15 +152,14 @@ > > static int annexb_probe(const AVProbeData *p) > > return 0; > > } > > > > -static int annexb_read_header(AVFormatContext *s) > > +static int read_header(AVFormatContext *s, AVRational framerate, > > +AVBSFContext **bsf, void *logctx) > > Nit: Maybe a pointer to framerate instead. I will change to const AVRational* framerate > > > { > > - AnnexBContext *c = s->priv_data; > > const AVBitStreamFilter *filter = > av_bsf_get_by_name("av1_frame_merge"); > > AVStream *st; > > int ret; > > > > if (!filter) { > > - av_log(c, AV_LOG_ERROR, "av1_frame_merge bitstream filter " > > + av_log(logctx, AV_LOG_ERROR, "av1_frame_merge bitstream filter " > > "not found. This is a bug, please report it.\n"); > > return AVERROR_BUG; > > } > > @@ -165,25 +172,32 @@ static int annexb_read_header(AVFormatContext > *s) > > st->codecpar->codec_id = AV_CODEC_ID_AV1; > > st->need_parsing = AVSTREAM_PARSE_HEADERS; > > > > - st->internal->avctx->framerate = c->framerate; > > + st->internal->avctx->framerate = framerate; > > // taken from rawvideo demuxers > > avpriv_set_pts_info(st, 64, 1, 1200000); > > > > - ret = av_bsf_alloc(filter, &c->bsf); > > + ret = av_bsf_alloc(filter, bsf); > > if (ret < 0) > > return ret; > > > > - ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar); > > + ret = avcodec_parameters_copy((*bsf)->par_in, st->codecpar); > > if (ret < 0) { > > - av_bsf_free(&c->bsf); > > + av_bsf_free(bsf); > > return ret; > > } > > > > - ret = av_bsf_init(c->bsf); > > + ret = av_bsf_init(*bsf); > > if (ret < 0) > > - av_bsf_free(&c->bsf); > > + av_bsf_free(bsf); > > > > return ret; > > + > > +} > > + > > +static int annexb_read_header(AVFormatContext *s) { > > + AnnexBContext *c = s->priv_data; > > + return read_header(s, c->framerate, &c->bsf, c); > > } > > > > static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt) @@ > > -251,12 +265,198 @@ static int annexb_read_close(AVFormatContext *s) > > return 0; > > } > > > > -#define OFFSET(x) offsetof(AnnexBContext, x) > > +typedef struct ObuContext { > > + const AVClass *class; > > + AVBSFContext *bsf; > > + AVRational framerate; > > + uint8_t prefetched[MAX_OBU_HEADER_SIZE]; > > + //prefetched len > > + int len; > > +} ObuContext; > > + > > +//For low overhead obu, we can't foresee the obu size before we parsed the > header. > > +//So, we can't use parse_obu_header here, since it will check size <= > > +buf_size //see c27c7b49dc for more details static int > > +read_obu_with_size(const uint8_t *buf, int buf_size, int64_t > > +*obu_size, int *type) { > > + GetBitContext gb; > > + int ret, extension_flag, start_pos; > > + int64_t size; > > + > > + ret = init_get_bits8(&gb, buf, FFMIN(buf_size, MAX_OBU_HEADER_SIZE)); > > + if (ret < 0) > > + return ret; > > + > > + if (get_bits1(&gb) != 0) // obu_forbidden_bit > > + return AVERROR_INVALIDDATA; > > + > > + *type = get_bits(&gb, 4); > > + extension_flag = get_bits1(&gb); > > + if (!get_bits1(&gb)) // has_size_flag > > + return AVERROR_INVALIDDATA; > > + skip_bits1(&gb); // obu_reserved_1bit > > + > > + if (extension_flag) { > > + get_bits(&gb, 3); // temporal_id > > + get_bits(&gb, 2); // spatial_id > > + skip_bits(&gb, 3); // extension_header_reserved_3bits > > + } > > + > > + *obu_size = leb128(&gb); > > + if (*obu_size > INT_MAX) > > + return AVERROR_INVALIDDATA; > > + > > + if (get_bits_left(&gb) < 0) > > + return AVERROR_INVALIDDATA; > > + > > + start_pos = get_bits_count(&gb) / 8; > > + > > + size = *obu_size + start_pos; > > + if (size > INT_MAX) > > + return AVERROR_INVALIDDATA; > > + return size; > > +} > > + > > +static int obu_probe(const AVProbeData *p) { > > + int64_t obu_size; > > + int seq = 0; > > + int ret, type, cnt; > > + > > + // Check that the first OBU is a Temporal Delimiter. > > + cnt = read_obu_with_size(p->buf, p->buf_size, &obu_size, &type); > > + if (cnt < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size != 0) > > + return 0; > > + > > + while (1) { > > + ret = read_obu_with_size(p->buf + cnt, p->buf_size - cnt, > > + &obu_size, &type); > > You need to ensure p->buf_size is bigger than cnt to avoid overreads when you I think about this before. It may not needed. If cnt>p->buf_size, init_get_bits_xe will report an error for init_get_bits8. See https://github.com/FFmpeg/FFmpeg/blob/c455a28a9e99d41d070be887228aa8609543b9a8/libavcodec/get_bits.h#L631 > attempt to skip to the next OBU, so use read_obu() here since you're passing the > entire buffer length and not just up to 10 bytes like in obu_get_packet() below. If we use read_obu, it will skip the check for has_size_flag. We may got a false positive. > The size <= buf_size check is needed here. If size>buf_size happens before AV1_OBU_FRAME/ AV1_OBU_FRAME_HEADER, we do not need check it. the function will return 0 since we can't find the frame obu. If it happens in frame obu, we only have part of frame in probe size. it's not big problem too, right? > > > + if (ret < 0 || obu_size <= 0) > > + return 0; > > + cnt += ret; > > + > > + ret = get_score(type, &seq); > > + if (ret >= 0) > > + return ret; > > + } > > + return 0; > > +} > > + > > +static int obu_read_header(AVFormatContext *s) { > > + ObuContext *c = s->priv_data; > > + return read_header(s, c->framerate, &c->bsf, c); } > > + > > +static int obu_prefetch(AVFormatContext *s) { > > + ObuContext *c = s->priv_data; > > + int ret; > > + int size = MAX_OBU_HEADER_SIZE - c->len; > > + if (size > 0 && !avio_feof(s->pb)) { > > + ret = avio_read(s->pb, &c->prefetched[c->len], size); > > + if (ret < 0) > > + return ret; > > + c->len += ret; > > + } > > + return c->len; > > +} > > + > > +static int obu_read_data(AVFormatContext *s, AVPacket *pkt, int size) > > +{ > > + int left; > > + ObuContext *c = s->priv_data; > > + int ret = av_new_packet(pkt, size); > > + if (ret < 0) { > > + av_log(c, AV_LOG_ERROR, "Failed to allocate packet for obu\n"); > > + return ret; > > + } > > + if (size <= c->len) { > > + memcpy(pkt->data, c->prefetched, size); > > + > > + left = c->len - size; > > + memmove(c->prefetched, c->prefetched + size, left); > > You can probably use av_fifo_* functions for the prefetch buffer. See > libavutil/fifo.h Could you explain more about this? It may save 1 or 2 lines of code here, but it's not benefit total code size or performance. > > > + c->len = left; > > + } else { > > + memcpy(pkt->data, c->prefetched, c->len); > > + left = size - c->len; > > + ret = avio_read(s->pb, pkt->data + c->len, left); > > + if (ret != left) { > > + av_log(c, AV_LOG_ERROR, "Failed to read %d frome file\n", left); > > + return ret; > > + } > > + c->len = 0; > > + } > > + return 0; > > +} > > + > > +static int obu_get_packet(AVFormatContext *s, AVPacket *pkt) { > > + int64_t obu_size; > > + int ret, type; > > + ObuContext *c = s->priv_data; > > + ret = obu_prefetch(s); > > + if (ret < 0) > > + return ret; > > + if (ret) { > > + ret = read_obu_with_size(c->prefetched, c->len, &obu_size, &type); > > + if (ret < 0) { > > + av_log(c, AV_LOG_ERROR, "Failed to read obu\n"); > > + return ret; > > + } > > + ret = obu_read_data(s, pkt, ret); > > + } > > + return ret; > > +} > > + > > +static int obu_read_packet(AVFormatContext *s, AVPacket *pkt) { > > + ObuContext *c = s->priv_data; > > + int ret; > > + > > + while (1) { > > + ret = obu_get_packet(s, pkt); > > + if (ret < 0) > > + return ret; > > + ret = av_bsf_send_packet(c->bsf, pkt); > > + if (ret < 0) { > > + av_log(s, AV_LOG_ERROR, "Failed to send packet to " > > + "av1_frame_merge filter\n"); > > + return ret; > > + } > > + ret = av_bsf_receive_packet(c->bsf, pkt); > > + if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF) > > + av_log(s, AV_LOG_ERROR, "av1_frame_merge filter failed to " > > + "send output packet\n"); > > + if (ret != AVERROR(EAGAIN)) > > + break; > > + } > > + > > + return ret; > > +} > > + > > +static int obu_read_close(AVFormatContext *s) { > > + ObuContext *c = s->priv_data; > > + > > + av_bsf_free(&c->bsf); > > + return 0; > > +} > > + > > #define DEC AV_OPT_FLAG_DECODING_PARAM > > + > > +#define OFFSET(x) offsetof(AnnexBContext, x) > > static const AVOption annexb_options[] = { > > { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = > "25"}, 0, INT_MAX, DEC}, > > { NULL }, > > }; > > +#undef OFFSET > > + > > +#define OFFSET(x) offsetof(ObuContext, x) static const AVOption > > +obu_options[] = { > > + { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = > "25"}, 0, INT_MAX, DEC}, > > + { NULL }, > > +}; > > +#undef OFFSET > > > > static const AVClass annexb_demuxer_class = { > > .class_name = "AV1 Annex B demuxer", @@ -277,3 +477,23 @@ > > AVInputFormat ff_av1_demuxer = { > > .flags = AVFMT_GENERIC_INDEX, > > .priv_class = &annexb_demuxer_class, > > }; > > + > > +static const AVClass obu_demuxer_class = { > > + .class_name = "AV1 low overhead OBU demuxer", > > + .item_name = av_default_item_name, > > + .option = obu_options, > > + .version = LIBAVUTIL_VERSION_INT, > > +}; > > + > > +AVInputFormat ff_obu_demuxer = { > > + .name = "obu", > > + .long_name = NULL_IF_CONFIG_SMALL("AV1 low overhead OBU"), > > + .priv_data_size = sizeof(ObuContext), > > + .read_probe = obu_probe, > > + .read_header = obu_read_header, > > + .read_packet = obu_read_packet, > > + .read_close = obu_read_close, > > + .extensions = "obu", > > + .flags = AVFMT_GENERIC_INDEX, > > + .priv_class = &obu_demuxer_class, > > +}; > > > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org > with subject "unsubscribe".
On 8/12/2020 9:53 PM, Xu, Guangxin wrote: > > Hi James, > Thanks for the review. > Comment in line. > >> -----Original Message----- >> From: ffmpeg-devel <ffmpeg-devel-bounces@ffmpeg.org> On Behalf Of James >> Almer >> Sent: Wednesday, August 12, 2020 9:06 PM >> To: ffmpeg-devel@ffmpeg.org >> Subject: Re: [FFmpeg-devel] [PATCH V2 2/3] avormat/av1dec: add low- >> overhead bitstream format >> >> On 8/10/2020 6:34 AM, Xu Guangxin wrote: >>> It's defined in Section 5.2, used by netflix. >>> see http://download.opencontent.netflix.com/?prefix=AV1/Chimera/ >>> --- >>> configure | 1 + >>> libavformat/allformats.c | 1 + >>> libavformat/av1dec.c | 266 +++++++++++++++++++++++++++++++++++-- >> -- >>> 3 files changed, 245 insertions(+), 23 deletions(-) >>> >>> diff --git a/configure b/configure >>> index 8de1afcb99..d4a1fea9ce 100755 >>> --- a/configure >>> +++ b/configure >>> @@ -3331,6 +3331,7 @@ mxf_d10_muxer_select="mxf_muxer" >>> mxf_opatom_muxer_select="mxf_muxer" >>> nut_muxer_select="riffenc" >>> nuv_demuxer_select="riffdec" >>> +obu_demuxer_select="av1_frame_merge_bsf av1_parser" >>> oga_muxer_select="ogg_muxer" >>> ogg_demuxer_select="dirac_parse" >>> ogv_muxer_select="ogg_muxer" >>> diff --git a/libavformat/allformats.c b/libavformat/allformats.c index >>> b7e59ae170..0aa9dd7198 100644 >>> --- a/libavformat/allformats.c >>> +++ b/libavformat/allformats.c >>> @@ -293,6 +293,7 @@ extern AVOutputFormat ff_null_muxer; extern >>> AVInputFormat ff_nut_demuxer; extern AVOutputFormat ff_nut_muxer; >>> extern AVInputFormat ff_nuv_demuxer; >>> +extern AVInputFormat ff_obu_demuxer; >>> extern AVOutputFormat ff_oga_muxer; >>> extern AVInputFormat ff_ogg_demuxer; extern AVOutputFormat >>> ff_ogg_muxer; diff --git a/libavformat/av1dec.c b/libavformat/av1dec.c >>> index 1be2fac1c1..14efb8f1d4 100644 >>> --- a/libavformat/av1dec.c >>> +++ b/libavformat/av1dec.c >>> @@ -70,6 +70,24 @@ static int read_obu(const uint8_t *buf, int size, int64_t >> *obu_size, int *type) >>> return 0; >>> } >>> >>> +//return < 0 if we need more data >>> +static int get_score(int type, int *seq) { >>> + switch (type) { >>> + case AV1_OBU_SEQUENCE_HEADER: >>> + *seq = 1; >>> + return -1; >>> + case AV1_OBU_FRAME: >>> + case AV1_OBU_FRAME_HEADER: >>> + return *seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; >>> + case AV1_OBU_METADATA: >>> + return -1; >>> + default: >>> + break; >> >> Padding OBU should be ignored/skipped, same as Metadata. This function >> should make the caller abort only for OBUs that are not meant to appear before >> a Frame/Frame Header (Tile list, Tile Group, Redundant Frame Header, another >> Temporal Delimiter). > Sure, I will add padding to allow list. > >> >>> + } >>> + return 0; >>> +} >>> + >>> static int annexb_probe(const AVProbeData *p) { >>> AVIOContext pb; >>> @@ -123,19 +141,9 @@ static int annexb_probe(const AVProbeData *p) >>> return 0; >>> cnt += obu_unit_size; >>> >>> - switch (type) { >>> - case AV1_OBU_SEQUENCE_HEADER: >>> - seq = 1; >>> - break; >>> - case AV1_OBU_FRAME: >>> - case AV1_OBU_FRAME_HEADER: >>> - return seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; >>> - case AV1_OBU_TILE_GROUP: >>> - case AV1_OBU_TEMPORAL_DELIMITER: >>> - return 0; >>> - default: >>> - break; >>> - } >>> + ret = get_score(type, &seq); >>> + if (ret >= 0) >>> + return ret; >>> >>> temporal_unit_size -= obu_unit_size + ret; >>> frame_unit_size -= obu_unit_size + ret; @@ -144,15 +152,14 @@ >>> static int annexb_probe(const AVProbeData *p) >>> return 0; >>> } >>> >>> -static int annexb_read_header(AVFormatContext *s) >>> +static int read_header(AVFormatContext *s, AVRational framerate, >>> +AVBSFContext **bsf, void *logctx) >> >> Nit: Maybe a pointer to framerate instead. > I will change to > const AVRational* framerate > >> >>> { >>> - AnnexBContext *c = s->priv_data; >>> const AVBitStreamFilter *filter = >> av_bsf_get_by_name("av1_frame_merge"); >>> AVStream *st; >>> int ret; >>> >>> if (!filter) { >>> - av_log(c, AV_LOG_ERROR, "av1_frame_merge bitstream filter " >>> + av_log(logctx, AV_LOG_ERROR, "av1_frame_merge bitstream filter " >>> "not found. This is a bug, please report it.\n"); >>> return AVERROR_BUG; >>> } >>> @@ -165,25 +172,32 @@ static int annexb_read_header(AVFormatContext >> *s) >>> st->codecpar->codec_id = AV_CODEC_ID_AV1; >>> st->need_parsing = AVSTREAM_PARSE_HEADERS; >>> >>> - st->internal->avctx->framerate = c->framerate; >>> + st->internal->avctx->framerate = framerate; >>> // taken from rawvideo demuxers >>> avpriv_set_pts_info(st, 64, 1, 1200000); >>> >>> - ret = av_bsf_alloc(filter, &c->bsf); >>> + ret = av_bsf_alloc(filter, bsf); >>> if (ret < 0) >>> return ret; >>> >>> - ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar); >>> + ret = avcodec_parameters_copy((*bsf)->par_in, st->codecpar); >>> if (ret < 0) { >>> - av_bsf_free(&c->bsf); >>> + av_bsf_free(bsf); >>> return ret; >>> } >>> >>> - ret = av_bsf_init(c->bsf); >>> + ret = av_bsf_init(*bsf); >>> if (ret < 0) >>> - av_bsf_free(&c->bsf); >>> + av_bsf_free(bsf); >>> >>> return ret; >>> + >>> +} >>> + >>> +static int annexb_read_header(AVFormatContext *s) { >>> + AnnexBContext *c = s->priv_data; >>> + return read_header(s, c->framerate, &c->bsf, c); >>> } >>> >>> static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt) @@ >>> -251,12 +265,198 @@ static int annexb_read_close(AVFormatContext *s) >>> return 0; >>> } >>> >>> -#define OFFSET(x) offsetof(AnnexBContext, x) >>> +typedef struct ObuContext { >>> + const AVClass *class; >>> + AVBSFContext *bsf; >>> + AVRational framerate; >>> + uint8_t prefetched[MAX_OBU_HEADER_SIZE]; >>> + //prefetched len >>> + int len; >>> +} ObuContext; >>> + >>> +//For low overhead obu, we can't foresee the obu size before we parsed the >> header. >>> +//So, we can't use parse_obu_header here, since it will check size <= >>> +buf_size //see c27c7b49dc for more details static int >>> +read_obu_with_size(const uint8_t *buf, int buf_size, int64_t >>> +*obu_size, int *type) { >>> + GetBitContext gb; >>> + int ret, extension_flag, start_pos; >>> + int64_t size; >>> + >>> + ret = init_get_bits8(&gb, buf, FFMIN(buf_size, MAX_OBU_HEADER_SIZE)); >>> + if (ret < 0) >>> + return ret; >>> + >>> + if (get_bits1(&gb) != 0) // obu_forbidden_bit >>> + return AVERROR_INVALIDDATA; >>> + >>> + *type = get_bits(&gb, 4); >>> + extension_flag = get_bits1(&gb); >>> + if (!get_bits1(&gb)) // has_size_flag >>> + return AVERROR_INVALIDDATA; >>> + skip_bits1(&gb); // obu_reserved_1bit >>> + >>> + if (extension_flag) { >>> + get_bits(&gb, 3); // temporal_id >>> + get_bits(&gb, 2); // spatial_id >>> + skip_bits(&gb, 3); // extension_header_reserved_3bits >>> + } >>> + >>> + *obu_size = leb128(&gb); >>> + if (*obu_size > INT_MAX) >>> + return AVERROR_INVALIDDATA; >>> + >>> + if (get_bits_left(&gb) < 0) >>> + return AVERROR_INVALIDDATA; >>> + >>> + start_pos = get_bits_count(&gb) / 8; >>> + >>> + size = *obu_size + start_pos; >>> + if (size > INT_MAX) >>> + return AVERROR_INVALIDDATA; >>> + return size; >>> +} >>> + >>> +static int obu_probe(const AVProbeData *p) { >>> + int64_t obu_size; >>> + int seq = 0; >>> + int ret, type, cnt; >>> + >>> + // Check that the first OBU is a Temporal Delimiter. >>> + cnt = read_obu_with_size(p->buf, p->buf_size, &obu_size, &type); >>> + if (cnt < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size != 0) >>> + return 0; >>> + >>> + while (1) { >>> + ret = read_obu_with_size(p->buf + cnt, p->buf_size - cnt, >>> + &obu_size, &type); >> >> You need to ensure p->buf_size is bigger than cnt to avoid overreads when you > I think about this before. It may not needed. > If cnt>p->buf_size, init_get_bits_xe will report an error for init_get_bits8. > See https://github.com/FFmpeg/FFmpeg/blob/c455a28a9e99d41d070be887228aa8609543b9a8/libavcodec/get_bits.h#L631 Yeah, did not consider the fact that init_get_bits() will fail on < 0 size arguments. > >> attempt to skip to the next OBU, so use read_obu() here since you're passing the >> entire buffer length and not just up to 10 bytes like in obu_get_packet() below. > If we use read_obu, it will skip the check for has_size_flag. We may got a false positive. > >> The size <= buf_size check is needed here. > If size>buf_size happens before AV1_OBU_FRAME/ AV1_OBU_FRAME_HEADER, we do not need check it. the function will return 0 since we can't find the frame obu. > If it happens in frame obu, we only have part of frame in probe size. it's not big problem too, right? > >> >>> + if (ret < 0 || obu_size <= 0) >>> + return 0; >>> + cnt += ret; >>> + >>> + ret = get_score(type, &seq); >>> + if (ret >= 0) >>> + return ret; >>> + } >>> + return 0; >>> +} >>> + >>> +static int obu_read_header(AVFormatContext *s) { >>> + ObuContext *c = s->priv_data; >>> + return read_header(s, c->framerate, &c->bsf, c); } >>> + >>> +static int obu_prefetch(AVFormatContext *s) { >>> + ObuContext *c = s->priv_data; >>> + int ret; >>> + int size = MAX_OBU_HEADER_SIZE - c->len; >>> + if (size > 0 && !avio_feof(s->pb)) { >>> + ret = avio_read(s->pb, &c->prefetched[c->len], size); >>> + if (ret < 0) >>> + return ret; >>> + c->len += ret; >>> + } >>> + return c->len; >>> +} >>> + >>> +static int obu_read_data(AVFormatContext *s, AVPacket *pkt, int size) >>> +{ >>> + int left; >>> + ObuContext *c = s->priv_data; >>> + int ret = av_new_packet(pkt, size); >>> + if (ret < 0) { >>> + av_log(c, AV_LOG_ERROR, "Failed to allocate packet for obu\n"); >>> + return ret; >>> + } >>> + if (size <= c->len) { >>> + memcpy(pkt->data, c->prefetched, size); >>> + >>> + left = c->len - size; >>> + memmove(c->prefetched, c->prefetched + size, left); >> >> You can probably use av_fifo_* functions for the prefetch buffer. See >> libavutil/fifo.h > Could you explain more about this? > It may save 1 or 2 lines of code here, but it's not benefit total code size or performance. It may save a few lines of code, it communicates the intent more clearly to anyone reading the code, and avoids reimplementing a FIFO in this demuxer when there's a public API available specifically for that purpose. You can even pass a custom function to av_fifo_generic_write() to read the data directly from s->pb. > >> >>> + c->len = left; >>> + } else { >>> + memcpy(pkt->data, c->prefetched, c->len); >>> + left = size - c->len; >>> + ret = avio_read(s->pb, pkt->data + c->len, left); >>> + if (ret != left) { >>> + av_log(c, AV_LOG_ERROR, "Failed to read %d frome file\n", left); >>> + return ret; >>> + } >>> + c->len = 0; >>> + } >>> + return 0; >>> +} >>> + >>> +static int obu_get_packet(AVFormatContext *s, AVPacket *pkt) { >>> + int64_t obu_size; >>> + int ret, type; >>> + ObuContext *c = s->priv_data; >>> + ret = obu_prefetch(s); >>> + if (ret < 0) >>> + return ret; >>> + if (ret) { >>> + ret = read_obu_with_size(c->prefetched, c->len, &obu_size, &type); >>> + if (ret < 0) { >>> + av_log(c, AV_LOG_ERROR, "Failed to read obu\n"); >>> + return ret; >>> + } >>> + ret = obu_read_data(s, pkt, ret); >>> + } >>> + return ret; >>> +} >>> + >>> +static int obu_read_packet(AVFormatContext *s, AVPacket *pkt) { >>> + ObuContext *c = s->priv_data; >>> + int ret; >>> + >>> + while (1) { >>> + ret = obu_get_packet(s, pkt); >>> + if (ret < 0) >>> + return ret; >>> + ret = av_bsf_send_packet(c->bsf, pkt); >>> + if (ret < 0) { >>> + av_log(s, AV_LOG_ERROR, "Failed to send packet to " >>> + "av1_frame_merge filter\n"); >>> + return ret; >>> + } >>> + ret = av_bsf_receive_packet(c->bsf, pkt); >>> + if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF) >>> + av_log(s, AV_LOG_ERROR, "av1_frame_merge filter failed to " >>> + "send output packet\n"); >>> + if (ret != AVERROR(EAGAIN)) >>> + break; >>> + } >>> + >>> + return ret; >>> +} >>> + >>> +static int obu_read_close(AVFormatContext *s) { >>> + ObuContext *c = s->priv_data; >>> + >>> + av_bsf_free(&c->bsf); >>> + return 0; >>> +} >>> + >>> #define DEC AV_OPT_FLAG_DECODING_PARAM >>> + >>> +#define OFFSET(x) offsetof(AnnexBContext, x) >>> static const AVOption annexb_options[] = { >>> { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = >> "25"}, 0, INT_MAX, DEC}, >>> { NULL }, >>> }; >>> +#undef OFFSET >>> + >>> +#define OFFSET(x) offsetof(ObuContext, x) static const AVOption >>> +obu_options[] = { >>> + { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = >> "25"}, 0, INT_MAX, DEC}, >>> + { NULL }, >>> +}; >>> +#undef OFFSET >>> >>> static const AVClass annexb_demuxer_class = { >>> .class_name = "AV1 Annex B demuxer", @@ -277,3 +477,23 @@ >>> AVInputFormat ff_av1_demuxer = { >>> .flags = AVFMT_GENERIC_INDEX, >>> .priv_class = &annexb_demuxer_class, >>> }; >>> + >>> +static const AVClass obu_demuxer_class = { >>> + .class_name = "AV1 low overhead OBU demuxer", >>> + .item_name = av_default_item_name, >>> + .option = obu_options, >>> + .version = LIBAVUTIL_VERSION_INT, >>> +}; >>> + >>> +AVInputFormat ff_obu_demuxer = { >>> + .name = "obu", >>> + .long_name = NULL_IF_CONFIG_SMALL("AV1 low overhead OBU"), >>> + .priv_data_size = sizeof(ObuContext), >>> + .read_probe = obu_probe, >>> + .read_header = obu_read_header, >>> + .read_packet = obu_read_packet, >>> + .read_close = obu_read_close, >>> + .extensions = "obu", >>> + .flags = AVFMT_GENERIC_INDEX, >>> + .priv_class = &obu_demuxer_class, >>> +}; >>> >> >> _______________________________________________ >> ffmpeg-devel mailing list >> ffmpeg-devel@ffmpeg.org >> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> >> To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org >> with subject "unsubscribe". > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe". >
diff --git a/configure b/configure index 8de1afcb99..d4a1fea9ce 100755 --- a/configure +++ b/configure @@ -3331,6 +3331,7 @@ mxf_d10_muxer_select="mxf_muxer" mxf_opatom_muxer_select="mxf_muxer" nut_muxer_select="riffenc" nuv_demuxer_select="riffdec" +obu_demuxer_select="av1_frame_merge_bsf av1_parser" oga_muxer_select="ogg_muxer" ogg_demuxer_select="dirac_parse" ogv_muxer_select="ogg_muxer" diff --git a/libavformat/allformats.c b/libavformat/allformats.c index b7e59ae170..0aa9dd7198 100644 --- a/libavformat/allformats.c +++ b/libavformat/allformats.c @@ -293,6 +293,7 @@ extern AVOutputFormat ff_null_muxer; extern AVInputFormat ff_nut_demuxer; extern AVOutputFormat ff_nut_muxer; extern AVInputFormat ff_nuv_demuxer; +extern AVInputFormat ff_obu_demuxer; extern AVOutputFormat ff_oga_muxer; extern AVInputFormat ff_ogg_demuxer; extern AVOutputFormat ff_ogg_muxer; diff --git a/libavformat/av1dec.c b/libavformat/av1dec.c index 1be2fac1c1..14efb8f1d4 100644 --- a/libavformat/av1dec.c +++ b/libavformat/av1dec.c @@ -70,6 +70,24 @@ static int read_obu(const uint8_t *buf, int size, int64_t *obu_size, int *type) return 0; } +//return < 0 if we need more data +static int get_score(int type, int *seq) +{ + switch (type) { + case AV1_OBU_SEQUENCE_HEADER: + *seq = 1; + return -1; + case AV1_OBU_FRAME: + case AV1_OBU_FRAME_HEADER: + return *seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; + case AV1_OBU_METADATA: + return -1; + default: + break; + } + return 0; +} + static int annexb_probe(const AVProbeData *p) { AVIOContext pb; @@ -123,19 +141,9 @@ static int annexb_probe(const AVProbeData *p) return 0; cnt += obu_unit_size; - switch (type) { - case AV1_OBU_SEQUENCE_HEADER: - seq = 1; - break; - case AV1_OBU_FRAME: - case AV1_OBU_FRAME_HEADER: - return seq ? AVPROBE_SCORE_EXTENSION + 1 : 0; - case AV1_OBU_TILE_GROUP: - case AV1_OBU_TEMPORAL_DELIMITER: - return 0; - default: - break; - } + ret = get_score(type, &seq); + if (ret >= 0) + return ret; temporal_unit_size -= obu_unit_size + ret; frame_unit_size -= obu_unit_size + ret; @@ -144,15 +152,14 @@ static int annexb_probe(const AVProbeData *p) return 0; } -static int annexb_read_header(AVFormatContext *s) +static int read_header(AVFormatContext *s, AVRational framerate, AVBSFContext **bsf, void *logctx) { - AnnexBContext *c = s->priv_data; const AVBitStreamFilter *filter = av_bsf_get_by_name("av1_frame_merge"); AVStream *st; int ret; if (!filter) { - av_log(c, AV_LOG_ERROR, "av1_frame_merge bitstream filter " + av_log(logctx, AV_LOG_ERROR, "av1_frame_merge bitstream filter " "not found. This is a bug, please report it.\n"); return AVERROR_BUG; } @@ -165,25 +172,32 @@ static int annexb_read_header(AVFormatContext *s) st->codecpar->codec_id = AV_CODEC_ID_AV1; st->need_parsing = AVSTREAM_PARSE_HEADERS; - st->internal->avctx->framerate = c->framerate; + st->internal->avctx->framerate = framerate; // taken from rawvideo demuxers avpriv_set_pts_info(st, 64, 1, 1200000); - ret = av_bsf_alloc(filter, &c->bsf); + ret = av_bsf_alloc(filter, bsf); if (ret < 0) return ret; - ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar); + ret = avcodec_parameters_copy((*bsf)->par_in, st->codecpar); if (ret < 0) { - av_bsf_free(&c->bsf); + av_bsf_free(bsf); return ret; } - ret = av_bsf_init(c->bsf); + ret = av_bsf_init(*bsf); if (ret < 0) - av_bsf_free(&c->bsf); + av_bsf_free(bsf); return ret; + +} + +static int annexb_read_header(AVFormatContext *s) +{ + AnnexBContext *c = s->priv_data; + return read_header(s, c->framerate, &c->bsf, c); } static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt) @@ -251,12 +265,198 @@ static int annexb_read_close(AVFormatContext *s) return 0; } -#define OFFSET(x) offsetof(AnnexBContext, x) +typedef struct ObuContext { + const AVClass *class; + AVBSFContext *bsf; + AVRational framerate; + uint8_t prefetched[MAX_OBU_HEADER_SIZE]; + //prefetched len + int len; +} ObuContext; + +//For low overhead obu, we can't foresee the obu size before we parsed the header. +//So, we can't use parse_obu_header here, since it will check size <= buf_size +//see c27c7b49dc for more details +static int read_obu_with_size(const uint8_t *buf, int buf_size, int64_t *obu_size, int *type) +{ + GetBitContext gb; + int ret, extension_flag, start_pos; + int64_t size; + + ret = init_get_bits8(&gb, buf, FFMIN(buf_size, MAX_OBU_HEADER_SIZE)); + if (ret < 0) + return ret; + + if (get_bits1(&gb) != 0) // obu_forbidden_bit + return AVERROR_INVALIDDATA; + + *type = get_bits(&gb, 4); + extension_flag = get_bits1(&gb); + if (!get_bits1(&gb)) // has_size_flag + return AVERROR_INVALIDDATA; + skip_bits1(&gb); // obu_reserved_1bit + + if (extension_flag) { + get_bits(&gb, 3); // temporal_id + get_bits(&gb, 2); // spatial_id + skip_bits(&gb, 3); // extension_header_reserved_3bits + } + + *obu_size = leb128(&gb); + if (*obu_size > INT_MAX) + return AVERROR_INVALIDDATA; + + if (get_bits_left(&gb) < 0) + return AVERROR_INVALIDDATA; + + start_pos = get_bits_count(&gb) / 8; + + size = *obu_size + start_pos; + if (size > INT_MAX) + return AVERROR_INVALIDDATA; + return size; +} + +static int obu_probe(const AVProbeData *p) +{ + int64_t obu_size; + int seq = 0; + int ret, type, cnt; + + // Check that the first OBU is a Temporal Delimiter. + cnt = read_obu_with_size(p->buf, p->buf_size, &obu_size, &type); + if (cnt < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size != 0) + return 0; + + while (1) { + ret = read_obu_with_size(p->buf + cnt, p->buf_size - cnt, &obu_size, &type); + if (ret < 0 || obu_size <= 0) + return 0; + cnt += ret; + + ret = get_score(type, &seq); + if (ret >= 0) + return ret; + } + return 0; +} + +static int obu_read_header(AVFormatContext *s) +{ + ObuContext *c = s->priv_data; + return read_header(s, c->framerate, &c->bsf, c); +} + +static int obu_prefetch(AVFormatContext *s) +{ + ObuContext *c = s->priv_data; + int ret; + int size = MAX_OBU_HEADER_SIZE - c->len; + if (size > 0 && !avio_feof(s->pb)) { + ret = avio_read(s->pb, &c->prefetched[c->len], size); + if (ret < 0) + return ret; + c->len += ret; + } + return c->len; +} + +static int obu_read_data(AVFormatContext *s, AVPacket *pkt, int size) +{ + int left; + ObuContext *c = s->priv_data; + int ret = av_new_packet(pkt, size); + if (ret < 0) { + av_log(c, AV_LOG_ERROR, "Failed to allocate packet for obu\n"); + return ret; + } + if (size <= c->len) { + memcpy(pkt->data, c->prefetched, size); + + left = c->len - size; + memmove(c->prefetched, c->prefetched + size, left); + c->len = left; + } else { + memcpy(pkt->data, c->prefetched, c->len); + left = size - c->len; + ret = avio_read(s->pb, pkt->data + c->len, left); + if (ret != left) { + av_log(c, AV_LOG_ERROR, "Failed to read %d frome file\n", left); + return ret; + } + c->len = 0; + } + return 0; +} + +static int obu_get_packet(AVFormatContext *s, AVPacket *pkt) +{ + int64_t obu_size; + int ret, type; + ObuContext *c = s->priv_data; + ret = obu_prefetch(s); + if (ret < 0) + return ret; + if (ret) { + ret = read_obu_with_size(c->prefetched, c->len, &obu_size, &type); + if (ret < 0) { + av_log(c, AV_LOG_ERROR, "Failed to read obu\n"); + return ret; + } + ret = obu_read_data(s, pkt, ret); + } + return ret; +} + +static int obu_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + ObuContext *c = s->priv_data; + int ret; + + while (1) { + ret = obu_get_packet(s, pkt); + if (ret < 0) + return ret; + ret = av_bsf_send_packet(c->bsf, pkt); + if (ret < 0) { + av_log(s, AV_LOG_ERROR, "Failed to send packet to " + "av1_frame_merge filter\n"); + return ret; + } + ret = av_bsf_receive_packet(c->bsf, pkt); + if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF) + av_log(s, AV_LOG_ERROR, "av1_frame_merge filter failed to " + "send output packet\n"); + if (ret != AVERROR(EAGAIN)) + break; + } + + return ret; +} + +static int obu_read_close(AVFormatContext *s) +{ + ObuContext *c = s->priv_data; + + av_bsf_free(&c->bsf); + return 0; +} + #define DEC AV_OPT_FLAG_DECODING_PARAM + +#define OFFSET(x) offsetof(AnnexBContext, x) static const AVOption annexb_options[] = { { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC}, { NULL }, }; +#undef OFFSET + +#define OFFSET(x) offsetof(ObuContext, x) +static const AVOption obu_options[] = { + { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC}, + { NULL }, +}; +#undef OFFSET static const AVClass annexb_demuxer_class = { .class_name = "AV1 Annex B demuxer", @@ -277,3 +477,23 @@ AVInputFormat ff_av1_demuxer = { .flags = AVFMT_GENERIC_INDEX, .priv_class = &annexb_demuxer_class, }; + +static const AVClass obu_demuxer_class = { + .class_name = "AV1 low overhead OBU demuxer", + .item_name = av_default_item_name, + .option = obu_options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_obu_demuxer = { + .name = "obu", + .long_name = NULL_IF_CONFIG_SMALL("AV1 low overhead OBU"), + .priv_data_size = sizeof(ObuContext), + .read_probe = obu_probe, + .read_header = obu_read_header, + .read_packet = obu_read_packet, + .read_close = obu_read_close, + .extensions = "obu", + .flags = AVFMT_GENERIC_INDEX, + .priv_class = &obu_demuxer_class, +};