diff mbox

[FFmpeg-devel,5/5] avformat: add an AV1 Annex B demuxer

Message ID 20191111133615.543-6-jamrial@gmail.com
State New
Headers show

Commit Message

James Almer Nov. 11, 2019, 1:36 p.m. UTC
Signed-off-by: James Almer <jamrial@gmail.com>
---
 configure                |   1 +
 libavformat/Makefile     |   1 +
 libavformat/allformats.c |   1 +
 libavformat/obu.c        | 276 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 279 insertions(+)
 create mode 100644 libavformat/obu.c

Comments

Carl Eugen Hoyos Nov. 11, 2019, 5:36 p.m. UTC | #1
> Am 11.11.2019 um 22:36 schrieb James Almer <jamrial@gmail.com>:
> 
> +AVInputFormat ff_obu_demuxer = {
> +    .name           = "obu",

Why is the demuxer not called “av1”?

Thank you, Carl Eugen
(Sleepless in Japan)
James Almer Nov. 11, 2019, 7:01 p.m. UTC | #2
On 11/11/2019 2:36 PM, Carl Eugen Hoyos wrote:
> 
> 
>> Am 11.11.2019 um 22:36 schrieb James Almer <jamrial@gmail.com>:
>>
>> +AVInputFormat ff_obu_demuxer = {
>> +    .name           = "obu",
> 
> Why is the demuxer not called “av1”?
> 
> Thank you, Carl Eugen
> (Sleepless in Japan)

I liked obu more, being the extension used for Annex B encapsulated
samples, but i'm fine changing it to av1 if others prefer that.

The problem will be what to do with the eventual raw Section 5 OBU demuxer.
Andreas Rheinhardt Nov. 11, 2019, 7:28 p.m. UTC | #3
James Almer:
> Signed-off-by: James Almer <jamrial@gmail.com>
> ---
>  configure                |   1 +
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/obu.c        | 276 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 279 insertions(+)
>  create mode 100644 libavformat/obu.c
> 
> diff --git a/configure b/configure
> index 70f60997c1..a8dbba879d 100755
> --- a/configure
> +++ b/configure
> @@ -3293,6 +3293,7 @@ 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"
>  oga_muxer_select="ogg_muxer"
>  ogg_demuxer_select="dirac_parse"
>  ogv_muxer_select="ogg_muxer"
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 8251f8f657..9057d0358a 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -350,6 +350,7 @@ OBJS-$(CONFIG_NULL_MUXER)                += nullenc.o
>  OBJS-$(CONFIG_NUT_DEMUXER)               += nutdec.o nut.o isom.o
>  OBJS-$(CONFIG_NUT_MUXER)                 += nutenc.o nut.o
>  OBJS-$(CONFIG_NUV_DEMUXER)               += nuv.o
> +OBJS-$(CONFIG_OBU_DEMUXER)               += obu.o
>  OBJS-$(CONFIG_OGG_DEMUXER)               += oggdec.o         \
>                                              oggparsecelt.o   \
>                                              oggparsedaala.o  \
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index f7fea32b45..152644e9f9 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -282,6 +282,7 @@ extern AVInputFormat  ff_nut_demuxer;
>  extern AVOutputFormat ff_nut_muxer;
>  extern AVInputFormat  ff_nuv_demuxer;
>  extern AVOutputFormat ff_oga_muxer;
> +extern AVInputFormat  ff_obu_demuxer;
>  extern AVInputFormat  ff_ogg_demuxer;
>  extern AVOutputFormat ff_ogg_muxer;
>  extern AVOutputFormat ff_ogv_muxer;
> diff --git a/libavformat/obu.c b/libavformat/obu.c
> new file mode 100644
> index 0000000000..55a9c7d55f
> --- /dev/null
> +++ b/libavformat/obu.c
> @@ -0,0 +1,276 @@
> +/*
> + * AV1 Annex-B demuxer
> + * Copyright (c) 2019 James Almer <jamrial@gmail.com>
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "config.h"
> +
> +#include "libavutil/common.h"
> +#include "libavutil/opt.h"
> +#include "libavcodec/av1_parse.h"
> +#include "avformat.h"
> +#include "avio_internal.h"
> +#include "internal.h"
> +
> +typedef struct AnnexBContext {
> +    const AVClass *class;
> +    AVBSFContext *bsf;
> +    uint32_t temporal_unit_size;
> +    uint32_t frame_unit_size;
> +    AVRational framerate;
> +} AnnexBContext;
> +
> +static int leb(AVIOContext *pb, uint32_t *len) {
> +    int more, i = 0;
> +    uint8_t byte;
> +    *len = 0;
> +    do {
> +        unsigned bits;
> +        byte = avio_r8(pb);
> +        more = byte & 0x80;
> +        bits = byte & 0x7f;
> +        if (i <= 3 || (i == 4 && bits < (1 << 4)))
> +            *len |= bits << (i * 7);
> +        else if (bits)
> +            return AVERROR_INVALIDDATA;
> +        if (++i == 8 && more)
> +            return AVERROR_INVALIDDATA;
> +        if (pb->eof_reached || pb->error)
> +            return pb->error ? pb->error : AVERROR(EIO);
> +    } while (more);
> +    return i;
> +}
> +
> +static int read_obu(const uint8_t *buf, int size, int64_t *obu_size, int *type)
> +{
> +    int start_pos, temporal_id, spatial_id;
> +    int len;
> +
> +    len = parse_obu_header(buf, size, obu_size, &start_pos,
> +                           type, &temporal_id, &spatial_id);
> +    if (len < 0)
> +        return len;
> +
> +    return 0;
> +}
> +
> +static int annexb_probe(const AVProbeData *p)
> +{
> +    AVIOContext pb;
> +    int64_t obu_size;
> +    uint32_t temporal_unit_size, frame_unit_size, obu_unit_size;
> +    int seq = 0, frame_header = 0;
> +    int ret, type, cnt = 0;
> +
> +    ffio_init_context(&pb, p->buf, p->buf_size, 0,
> +                      NULL, NULL, NULL, NULL);
> +
> +    ret = leb(&pb, &temporal_unit_size);
> +    if (ret < 0)
> +        return 0;
> +    cnt += ret;
> +    ret = leb(&pb, &frame_unit_size);
> +    if (ret < 0 || (frame_unit_size + ret) > temporal_unit_size)
> +        return 0;
> +    cnt += ret;
> +    temporal_unit_size -= ret;
> +    ret = leb(&pb, &obu_unit_size);
> +    if (ret < 0 || (obu_unit_size + ret) >= frame_unit_size)
> +        return 0;
> +    cnt += ret;
> +
> +    temporal_unit_size -= obu_unit_size + ret;
> +    frame_unit_size -= obu_unit_size + ret;
> +
> +    avio_skip(&pb, obu_unit_size);
> +    if (pb.eof_reached || pb.error)
> +        return 0;
> +
> +    // Check that the first OBU is a Temporal Delimiter.
> +    ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
> +    if (ret < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size > 0)
> +        return 0;
> +    cnt += obu_unit_size;
> +
> +    do {
> +        ret = leb(&pb, &obu_unit_size);
> +        if (ret < 0 || (obu_unit_size + ret) > frame_unit_size)
> +            return 0;
> +        cnt += ret;
> +
> +        avio_skip(&pb, obu_unit_size);
> +        if (pb.eof_reached || pb.error)
> +            return 0;
> +
> +        ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
> +        if (ret < 0)
> +            return 0;
> +        cnt += obu_unit_size;
> +
> +        if (type == AV1_OBU_SEQUENCE_HEADER)
> +            seq = 1;
> +        if (type == AV1_OBU_FRAME || type == AV1_OBU_FRAME_HEADER) {
> +            if (frame_header || !seq)
> +                return 0;
> +            frame_header = 1;
> +            break;
> +        }
> +        if (type == AV1_OBU_TILE_GROUP && !frame_header)
> +            return 0;
> +
> +        temporal_unit_size -= obu_unit_size + ret;
> +        frame_unit_size -= obu_unit_size + ret;
> +    } while (!seq || !frame_header || frame_unit_size);
> +
> +    return (seq && frame_header) ? AVPROBE_SCORE_EXTENSION + 1 : 0;
> +}
> +
> +static int annexb_read_header(AVFormatContext *s)
> +{
> +    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 "
> +               "not found. This is a bug, please report it.\n");
> +        return AVERROR_BUG;
> +    }
> +
> +    st = avformat_new_stream(s, NULL);
> +    if (!st)
> +        return AVERROR(ENOMEM);
> +
> +    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
> +    st->codecpar->codec_id = AV_CODEC_ID_AV1;
> +    st->need_parsing = AVSTREAM_PARSE_HEADERS;
> +
> +    st->internal->avctx->framerate = c->framerate;
> +    // taken from rawvideo demuxers
> +    avpriv_set_pts_info(st, 64, 1, 1200000);
> +
> +    ret = av_bsf_alloc(filter, &c->bsf);
> +    if (ret < 0)
> +        return ret;
> +
> +    ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar);
> +    if (ret < 0) {
> +        av_bsf_free(&c->bsf);
> +        return ret;
> +    }
> +
> +    return av_bsf_init(c->bsf);

Demuxers don't have a deinit function, so if av_bsf_init() fails, no
one will clean up after you and free the bsf.

> +}
> +
> +static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> +    AnnexBContext *c = s->priv_data;
> +    uint32_t obu_unit_size;
> +    int ret, len;
> +
> +retry:
> +    if (avio_feof(s->pb)) {
> +        if (c->temporal_unit_size || c->frame_unit_size)
> +            return AVERROR(EIO);
> +        av_bsf_send_packet(c->bsf, NULL);
> +        goto end;
> +    }
> +
> +    if (!c->temporal_unit_size) {
> +        len = leb(s->pb, &c->temporal_unit_size);
> +        if (len < 0) return AVERROR_INVALIDDATA;
> +    }
> +
> +    if (!c->frame_unit_size) {
> +        len = leb(s->pb, &c->frame_unit_size);
> +        if (len < 0 || (c->frame_unit_size + len) > c->temporal_unit_size)
> +            return AVERROR_INVALIDDATA;
> +        c->temporal_unit_size -= len;
> +    }
> +
> +    len = leb(s->pb, &obu_unit_size);
> +    if (len < 0 || (obu_unit_size + len) > c->frame_unit_size)
> +        return AVERROR_INVALIDDATA;
> +
> +    ret = av_get_packet(s->pb, pkt, obu_unit_size);
> +    if (ret < 0)
> +        return ret;
> +    if (ret != obu_unit_size) {
> +        av_packet_unref(pkt);

This is unnecessary: ff_read_packet() will unref the packet if you
return an error. You added this yourself. (You are btw relying on this
by not unreferencing the packet if av_bsf_send_packet() fails.)

> +        return AVERROR(EIO);
> +    }
> +
> +    c->temporal_unit_size -= obu_unit_size + len;
> +    c->frame_unit_size -= obu_unit_size + len;
> +
> +    ret = av_bsf_send_packet(c->bsf, pkt);
> +    if (ret < 0) {
> +        av_log(s, AV_LOG_ERROR, "av1_frame_merge filter "
> +               "failed to send input packet\n");

"Failed to send packet to av1_frame_merge filter\n" (av1_frame_merge
does not send any input packet ever, it receives them; and this call
does not call any av1_frame_merge internal functions.)

> +        return ret;
> +    }
> +
> +end:
> +    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 receive output packet\n");

"av1_frame_merge filter failed to send output packet\n"

> +
> +    if (ret == AVERROR(EAGAIN))
> +        goto retry;
> +
> +    return ret;
> +}
> +
> +static int annexb_read_close(AVFormatContext *s)

Side-note: Why does read_close() have to return an int? The return
value is ignored in avformat_close_input(), the only place where
read_close() is ever called.

I haven't looked at the rest (i.e. probe and leb) yet, in particular
wrt overflows.

- Andreas
James Almer Nov. 11, 2019, 7:47 p.m. UTC | #4
On 11/11/2019 4:28 PM, Andreas Rheinhardt wrote:
> James Almer:
>> Signed-off-by: James Almer <jamrial@gmail.com>
>> ---
>>  configure                |   1 +
>>  libavformat/Makefile     |   1 +
>>  libavformat/allformats.c |   1 +
>>  libavformat/obu.c        | 276 +++++++++++++++++++++++++++++++++++++++
>>  4 files changed, 279 insertions(+)
>>  create mode 100644 libavformat/obu.c
>>
>> diff --git a/configure b/configure
>> index 70f60997c1..a8dbba879d 100755
>> --- a/configure
>> +++ b/configure
>> @@ -3293,6 +3293,7 @@ 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"
>>  oga_muxer_select="ogg_muxer"
>>  ogg_demuxer_select="dirac_parse"
>>  ogv_muxer_select="ogg_muxer"
>> diff --git a/libavformat/Makefile b/libavformat/Makefile
>> index 8251f8f657..9057d0358a 100644
>> --- a/libavformat/Makefile
>> +++ b/libavformat/Makefile
>> @@ -350,6 +350,7 @@ OBJS-$(CONFIG_NULL_MUXER)                += nullenc.o
>>  OBJS-$(CONFIG_NUT_DEMUXER)               += nutdec.o nut.o isom.o
>>  OBJS-$(CONFIG_NUT_MUXER)                 += nutenc.o nut.o
>>  OBJS-$(CONFIG_NUV_DEMUXER)               += nuv.o
>> +OBJS-$(CONFIG_OBU_DEMUXER)               += obu.o
>>  OBJS-$(CONFIG_OGG_DEMUXER)               += oggdec.o         \
>>                                              oggparsecelt.o   \
>>                                              oggparsedaala.o  \
>> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
>> index f7fea32b45..152644e9f9 100644
>> --- a/libavformat/allformats.c
>> +++ b/libavformat/allformats.c
>> @@ -282,6 +282,7 @@ extern AVInputFormat  ff_nut_demuxer;
>>  extern AVOutputFormat ff_nut_muxer;
>>  extern AVInputFormat  ff_nuv_demuxer;
>>  extern AVOutputFormat ff_oga_muxer;
>> +extern AVInputFormat  ff_obu_demuxer;
>>  extern AVInputFormat  ff_ogg_demuxer;
>>  extern AVOutputFormat ff_ogg_muxer;
>>  extern AVOutputFormat ff_ogv_muxer;
>> diff --git a/libavformat/obu.c b/libavformat/obu.c
>> new file mode 100644
>> index 0000000000..55a9c7d55f
>> --- /dev/null
>> +++ b/libavformat/obu.c
>> @@ -0,0 +1,276 @@
>> +/*
>> + * AV1 Annex-B demuxer
>> + * Copyright (c) 2019 James Almer <jamrial@gmail.com>
>> + *
>> + * This file is part of FFmpeg.
>> + *
>> + * FFmpeg is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU Lesser General Public
>> + * License as published by the Free Software Foundation; either
>> + * version 2.1 of the License, or (at your option) any later version.
>> + *
>> + * FFmpeg is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>> + * Lesser General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU Lesser General Public
>> + * License along with FFmpeg; if not, write to the Free Software
>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
>> + */
>> +
>> +#include "config.h"
>> +
>> +#include "libavutil/common.h"
>> +#include "libavutil/opt.h"
>> +#include "libavcodec/av1_parse.h"
>> +#include "avformat.h"
>> +#include "avio_internal.h"
>> +#include "internal.h"
>> +
>> +typedef struct AnnexBContext {
>> +    const AVClass *class;
>> +    AVBSFContext *bsf;
>> +    uint32_t temporal_unit_size;
>> +    uint32_t frame_unit_size;
>> +    AVRational framerate;
>> +} AnnexBContext;
>> +
>> +static int leb(AVIOContext *pb, uint32_t *len) {
>> +    int more, i = 0;
>> +    uint8_t byte;
>> +    *len = 0;
>> +    do {
>> +        unsigned bits;
>> +        byte = avio_r8(pb);
>> +        more = byte & 0x80;
>> +        bits = byte & 0x7f;
>> +        if (i <= 3 || (i == 4 && bits < (1 << 4)))
>> +            *len |= bits << (i * 7);
>> +        else if (bits)
>> +            return AVERROR_INVALIDDATA;
>> +        if (++i == 8 && more)
>> +            return AVERROR_INVALIDDATA;
>> +        if (pb->eof_reached || pb->error)
>> +            return pb->error ? pb->error : AVERROR(EIO);
>> +    } while (more);
>> +    return i;
>> +}
>> +
>> +static int read_obu(const uint8_t *buf, int size, int64_t *obu_size, int *type)
>> +{
>> +    int start_pos, temporal_id, spatial_id;
>> +    int len;
>> +
>> +    len = parse_obu_header(buf, size, obu_size, &start_pos,
>> +                           type, &temporal_id, &spatial_id);
>> +    if (len < 0)
>> +        return len;
>> +
>> +    return 0;
>> +}
>> +
>> +static int annexb_probe(const AVProbeData *p)
>> +{
>> +    AVIOContext pb;
>> +    int64_t obu_size;
>> +    uint32_t temporal_unit_size, frame_unit_size, obu_unit_size;
>> +    int seq = 0, frame_header = 0;
>> +    int ret, type, cnt = 0;
>> +
>> +    ffio_init_context(&pb, p->buf, p->buf_size, 0,
>> +                      NULL, NULL, NULL, NULL);
>> +
>> +    ret = leb(&pb, &temporal_unit_size);
>> +    if (ret < 0)
>> +        return 0;
>> +    cnt += ret;
>> +    ret = leb(&pb, &frame_unit_size);
>> +    if (ret < 0 || (frame_unit_size + ret) > temporal_unit_size)
>> +        return 0;
>> +    cnt += ret;
>> +    temporal_unit_size -= ret;
>> +    ret = leb(&pb, &obu_unit_size);
>> +    if (ret < 0 || (obu_unit_size + ret) >= frame_unit_size)
>> +        return 0;
>> +    cnt += ret;
>> +
>> +    temporal_unit_size -= obu_unit_size + ret;
>> +    frame_unit_size -= obu_unit_size + ret;
>> +
>> +    avio_skip(&pb, obu_unit_size);
>> +    if (pb.eof_reached || pb.error)
>> +        return 0;
>> +
>> +    // Check that the first OBU is a Temporal Delimiter.
>> +    ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
>> +    if (ret < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size > 0)
>> +        return 0;
>> +    cnt += obu_unit_size;
>> +
>> +    do {
>> +        ret = leb(&pb, &obu_unit_size);
>> +        if (ret < 0 || (obu_unit_size + ret) > frame_unit_size)
>> +            return 0;
>> +        cnt += ret;
>> +
>> +        avio_skip(&pb, obu_unit_size);
>> +        if (pb.eof_reached || pb.error)
>> +            return 0;
>> +
>> +        ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
>> +        if (ret < 0)
>> +            return 0;
>> +        cnt += obu_unit_size;
>> +
>> +        if (type == AV1_OBU_SEQUENCE_HEADER)
>> +            seq = 1;
>> +        if (type == AV1_OBU_FRAME || type == AV1_OBU_FRAME_HEADER) {
>> +            if (frame_header || !seq)
>> +                return 0;
>> +            frame_header = 1;
>> +            break;
>> +        }
>> +        if (type == AV1_OBU_TILE_GROUP && !frame_header)
>> +            return 0;
>> +
>> +        temporal_unit_size -= obu_unit_size + ret;
>> +        frame_unit_size -= obu_unit_size + ret;
>> +    } while (!seq || !frame_header || frame_unit_size);
>> +
>> +    return (seq && frame_header) ? AVPROBE_SCORE_EXTENSION + 1 : 0;
>> +}
>> +
>> +static int annexb_read_header(AVFormatContext *s)
>> +{
>> +    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 "
>> +               "not found. This is a bug, please report it.\n");
>> +        return AVERROR_BUG;
>> +    }
>> +
>> +    st = avformat_new_stream(s, NULL);
>> +    if (!st)
>> +        return AVERROR(ENOMEM);
>> +
>> +    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
>> +    st->codecpar->codec_id = AV_CODEC_ID_AV1;
>> +    st->need_parsing = AVSTREAM_PARSE_HEADERS;
>> +
>> +    st->internal->avctx->framerate = c->framerate;
>> +    // taken from rawvideo demuxers
>> +    avpriv_set_pts_info(st, 64, 1, 1200000);
>> +
>> +    ret = av_bsf_alloc(filter, &c->bsf);
>> +    if (ret < 0)
>> +        return ret;
>> +
>> +    ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar);
>> +    if (ret < 0) {
>> +        av_bsf_free(&c->bsf);
>> +        return ret;
>> +    }
>> +
>> +    return av_bsf_init(c->bsf);
> 
> Demuxers don't have a deinit function, so if av_bsf_init() fails, no
> one will clean up after you and free the bsf.

True, will change.

> 
>> +}
>> +
>> +static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt)
>> +{
>> +    AnnexBContext *c = s->priv_data;
>> +    uint32_t obu_unit_size;
>> +    int ret, len;
>> +
>> +retry:
>> +    if (avio_feof(s->pb)) {
>> +        if (c->temporal_unit_size || c->frame_unit_size)
>> +            return AVERROR(EIO);
>> +        av_bsf_send_packet(c->bsf, NULL);
>> +        goto end;
>> +    }
>> +
>> +    if (!c->temporal_unit_size) {
>> +        len = leb(s->pb, &c->temporal_unit_size);
>> +        if (len < 0) return AVERROR_INVALIDDATA;
>> +    }
>> +
>> +    if (!c->frame_unit_size) {
>> +        len = leb(s->pb, &c->frame_unit_size);
>> +        if (len < 0 || (c->frame_unit_size + len) > c->temporal_unit_size)
>> +            return AVERROR_INVALIDDATA;
>> +        c->temporal_unit_size -= len;
>> +    }
>> +
>> +    len = leb(s->pb, &obu_unit_size);
>> +    if (len < 0 || (obu_unit_size + len) > c->frame_unit_size)
>> +        return AVERROR_INVALIDDATA;
>> +
>> +    ret = av_get_packet(s->pb, pkt, obu_unit_size);
>> +    if (ret < 0)
>> +        return ret;
>> +    if (ret != obu_unit_size) {
>> +        av_packet_unref(pkt);
> 
> This is unnecessary: ff_read_packet() will unref the packet if you
> return an error. You added this yourself. (You are btw relying on this
> by not unreferencing the packet if av_bsf_send_packet() fails.)

Will remove.

> 
>> +        return AVERROR(EIO);
>> +    }
>> +
>> +    c->temporal_unit_size -= obu_unit_size + len;
>> +    c->frame_unit_size -= obu_unit_size + len;
>> +
>> +    ret = av_bsf_send_packet(c->bsf, pkt);
>> +    if (ret < 0) {
>> +        av_log(s, AV_LOG_ERROR, "av1_frame_merge filter "
>> +               "failed to send input packet\n");
> 
> "Failed to send packet to av1_frame_merge filter\n" (av1_frame_merge
> does not send any input packet ever, it receives them; and this call
> does not call any av1_frame_merge internal functions.)

It's pretty much a copy paste log message from another module. I'll
change it and the one below.

> 
>> +        return ret;
>> +    }
>> +
>> +end:
>> +    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 receive output packet\n");
> 
> "av1_frame_merge filter failed to send output packet\n"
> 
>> +
>> +    if (ret == AVERROR(EAGAIN))
>> +        goto retry;
>> +
>> +    return ret;
>> +}
>> +
>> +static int annexb_read_close(AVFormatContext *s)
> 
> Side-note: Why does read_close() have to return an int? The return
> value is ignored in avformat_close_input(), the only place where
> read_close() is ever called.

I don't know. I also wondered about that. Every other close function is
 a void (codecs, filters, etc).
It may have been done for a reason at some point, but in any case, it's
hardly important.

> 
> I haven't looked at the rest (i.e. probe and leb) yet, in particular
> wrt overflows.

Things like "frame_unit_size + ret" could in theory overflow, with
frame_unit_size being of type uint32_t and possible values up to
UINT32_MAX. I could cast it to int64_t to workaround that.

> 
> - Andreas
> _______________________________________________
> 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".
>
Carl Eugen Hoyos Nov. 13, 2019, 3:20 a.m. UTC | #5
> Am 12.11.2019 um 04:01 schrieb James Almer <jamrial@gmail.com>:
> 
>> On 11/11/2019 2:36 PM, Carl Eugen Hoyos wrote:
>> 
>> 
>>> Am 11.11.2019 um 22:36 schrieb James Almer <jamrial@gmail.com>:
>>> 
>>> +AVInputFormat ff_obu_demuxer = {
>>> +    .name           = "obu",
>> 
>> Why is the demuxer not called “av1”?
>> 
>> Thank you, Carl Eugen
>> (Sleepless in Japan)
> 
> I liked obu more, being the extension used for Annex B encapsulated
> samples, but i'm fine changing it to av1 if others prefer that.

I would have preferred av1 ...

> 
> The problem will be what to do with the eventual raw Section 5 OBU demuxer.

... but I have no idea what the Section 5 demuxer is (or which one of the two is more likely to need on occasion demuxer forcing).

Carl Eugen
James Almer Nov. 13, 2019, 3:34 a.m. UTC | #6
On 11/13/2019 12:20 AM, Carl Eugen Hoyos wrote:
> 
> 
>> Am 12.11.2019 um 04:01 schrieb James Almer <jamrial@gmail.com>:
>>
>>> On 11/11/2019 2:36 PM, Carl Eugen Hoyos wrote:
>>>
>>>
>>>> Am 11.11.2019 um 22:36 schrieb James Almer <jamrial@gmail.com>:
>>>>
>>>> +AVInputFormat ff_obu_demuxer = {
>>>> +    .name           = "obu",
>>>
>>> Why is the demuxer not called “av1”?
>>>
>>> Thank you, Carl Eugen
>>> (Sleepless in Japan)
>>
>> I liked obu more, being the extension used for Annex B encapsulated
>> samples, but i'm fine changing it to av1 if others prefer that.
> 
> I would have preferred av1 ...

You'll be happy to know i decided to go with your suggestion, then :p

> 
>>
>> The problem will be what to do with the eventual raw Section 5 OBU demuxer.
> 
> ... but I have no idea what the Section 5 demuxer is (or which one of the two is more likely to need on occasion demuxer forcing).

"Section 5" is just raw AV1 OBUs, and what gets multiplexed into
containers. It's similar to raw h264 NALUs.
"Annex B" is a trivial encapsulation for said raw OBUs, to easily
delimit frames and Temporal Units. I can barely be considered a container.

I called the Annex B demuxer av1. An eventual raw OBU demuxer can then
be called obu.

> 
> Carl Eugen
> _______________________________________________
> 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 mbox

Patch

diff --git a/configure b/configure
index 70f60997c1..a8dbba879d 100755
--- a/configure
+++ b/configure
@@ -3293,6 +3293,7 @@  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"
 oga_muxer_select="ogg_muxer"
 ogg_demuxer_select="dirac_parse"
 ogv_muxer_select="ogg_muxer"
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 8251f8f657..9057d0358a 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -350,6 +350,7 @@  OBJS-$(CONFIG_NULL_MUXER)                += nullenc.o
 OBJS-$(CONFIG_NUT_DEMUXER)               += nutdec.o nut.o isom.o
 OBJS-$(CONFIG_NUT_MUXER)                 += nutenc.o nut.o
 OBJS-$(CONFIG_NUV_DEMUXER)               += nuv.o
+OBJS-$(CONFIG_OBU_DEMUXER)               += obu.o
 OBJS-$(CONFIG_OGG_DEMUXER)               += oggdec.o         \
                                             oggparsecelt.o   \
                                             oggparsedaala.o  \
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index f7fea32b45..152644e9f9 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -282,6 +282,7 @@  extern AVInputFormat  ff_nut_demuxer;
 extern AVOutputFormat ff_nut_muxer;
 extern AVInputFormat  ff_nuv_demuxer;
 extern AVOutputFormat ff_oga_muxer;
+extern AVInputFormat  ff_obu_demuxer;
 extern AVInputFormat  ff_ogg_demuxer;
 extern AVOutputFormat ff_ogg_muxer;
 extern AVOutputFormat ff_ogv_muxer;
diff --git a/libavformat/obu.c b/libavformat/obu.c
new file mode 100644
index 0000000000..55a9c7d55f
--- /dev/null
+++ b/libavformat/obu.c
@@ -0,0 +1,276 @@ 
+/*
+ * AV1 Annex-B demuxer
+ * Copyright (c) 2019 James Almer <jamrial@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+
+#include "libavutil/common.h"
+#include "libavutil/opt.h"
+#include "libavcodec/av1_parse.h"
+#include "avformat.h"
+#include "avio_internal.h"
+#include "internal.h"
+
+typedef struct AnnexBContext {
+    const AVClass *class;
+    AVBSFContext *bsf;
+    uint32_t temporal_unit_size;
+    uint32_t frame_unit_size;
+    AVRational framerate;
+} AnnexBContext;
+
+static int leb(AVIOContext *pb, uint32_t *len) {
+    int more, i = 0;
+    uint8_t byte;
+    *len = 0;
+    do {
+        unsigned bits;
+        byte = avio_r8(pb);
+        more = byte & 0x80;
+        bits = byte & 0x7f;
+        if (i <= 3 || (i == 4 && bits < (1 << 4)))
+            *len |= bits << (i * 7);
+        else if (bits)
+            return AVERROR_INVALIDDATA;
+        if (++i == 8 && more)
+            return AVERROR_INVALIDDATA;
+        if (pb->eof_reached || pb->error)
+            return pb->error ? pb->error : AVERROR(EIO);
+    } while (more);
+    return i;
+}
+
+static int read_obu(const uint8_t *buf, int size, int64_t *obu_size, int *type)
+{
+    int start_pos, temporal_id, spatial_id;
+    int len;
+
+    len = parse_obu_header(buf, size, obu_size, &start_pos,
+                           type, &temporal_id, &spatial_id);
+    if (len < 0)
+        return len;
+
+    return 0;
+}
+
+static int annexb_probe(const AVProbeData *p)
+{
+    AVIOContext pb;
+    int64_t obu_size;
+    uint32_t temporal_unit_size, frame_unit_size, obu_unit_size;
+    int seq = 0, frame_header = 0;
+    int ret, type, cnt = 0;
+
+    ffio_init_context(&pb, p->buf, p->buf_size, 0,
+                      NULL, NULL, NULL, NULL);
+
+    ret = leb(&pb, &temporal_unit_size);
+    if (ret < 0)
+        return 0;
+    cnt += ret;
+    ret = leb(&pb, &frame_unit_size);
+    if (ret < 0 || (frame_unit_size + ret) > temporal_unit_size)
+        return 0;
+    cnt += ret;
+    temporal_unit_size -= ret;
+    ret = leb(&pb, &obu_unit_size);
+    if (ret < 0 || (obu_unit_size + ret) >= frame_unit_size)
+        return 0;
+    cnt += ret;
+
+    temporal_unit_size -= obu_unit_size + ret;
+    frame_unit_size -= obu_unit_size + ret;
+
+    avio_skip(&pb, obu_unit_size);
+    if (pb.eof_reached || pb.error)
+        return 0;
+
+    // Check that the first OBU is a Temporal Delimiter.
+    ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
+    if (ret < 0 || type != AV1_OBU_TEMPORAL_DELIMITER || obu_size > 0)
+        return 0;
+    cnt += obu_unit_size;
+
+    do {
+        ret = leb(&pb, &obu_unit_size);
+        if (ret < 0 || (obu_unit_size + ret) > frame_unit_size)
+            return 0;
+        cnt += ret;
+
+        avio_skip(&pb, obu_unit_size);
+        if (pb.eof_reached || pb.error)
+            return 0;
+
+        ret = read_obu(p->buf + cnt, FFMIN(p->buf_size - cnt, obu_unit_size), &obu_size, &type);
+        if (ret < 0)
+            return 0;
+        cnt += obu_unit_size;
+
+        if (type == AV1_OBU_SEQUENCE_HEADER)
+            seq = 1;
+        if (type == AV1_OBU_FRAME || type == AV1_OBU_FRAME_HEADER) {
+            if (frame_header || !seq)
+                return 0;
+            frame_header = 1;
+            break;
+        }
+        if (type == AV1_OBU_TILE_GROUP && !frame_header)
+            return 0;
+
+        temporal_unit_size -= obu_unit_size + ret;
+        frame_unit_size -= obu_unit_size + ret;
+    } while (!seq || !frame_header || frame_unit_size);
+
+    return (seq && frame_header) ? AVPROBE_SCORE_EXTENSION + 1 : 0;
+}
+
+static int annexb_read_header(AVFormatContext *s)
+{
+    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 "
+               "not found. This is a bug, please report it.\n");
+        return AVERROR_BUG;
+    }
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    st->codecpar->codec_id = AV_CODEC_ID_AV1;
+    st->need_parsing = AVSTREAM_PARSE_HEADERS;
+
+    st->internal->avctx->framerate = c->framerate;
+    // taken from rawvideo demuxers
+    avpriv_set_pts_info(st, 64, 1, 1200000);
+
+    ret = av_bsf_alloc(filter, &c->bsf);
+    if (ret < 0)
+        return ret;
+
+    ret = avcodec_parameters_copy(c->bsf->par_in, st->codecpar);
+    if (ret < 0) {
+        av_bsf_free(&c->bsf);
+        return ret;
+    }
+
+    return av_bsf_init(c->bsf);
+}
+
+static int annexb_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    AnnexBContext *c = s->priv_data;
+    uint32_t obu_unit_size;
+    int ret, len;
+
+retry:
+    if (avio_feof(s->pb)) {
+        if (c->temporal_unit_size || c->frame_unit_size)
+            return AVERROR(EIO);
+        av_bsf_send_packet(c->bsf, NULL);
+        goto end;
+    }
+
+    if (!c->temporal_unit_size) {
+        len = leb(s->pb, &c->temporal_unit_size);
+        if (len < 0) return AVERROR_INVALIDDATA;
+    }
+
+    if (!c->frame_unit_size) {
+        len = leb(s->pb, &c->frame_unit_size);
+        if (len < 0 || (c->frame_unit_size + len) > c->temporal_unit_size)
+            return AVERROR_INVALIDDATA;
+        c->temporal_unit_size -= len;
+    }
+
+    len = leb(s->pb, &obu_unit_size);
+    if (len < 0 || (obu_unit_size + len) > c->frame_unit_size)
+        return AVERROR_INVALIDDATA;
+
+    ret = av_get_packet(s->pb, pkt, obu_unit_size);
+    if (ret < 0)
+        return ret;
+    if (ret != obu_unit_size) {
+        av_packet_unref(pkt);
+        return AVERROR(EIO);
+    }
+
+    c->temporal_unit_size -= obu_unit_size + len;
+    c->frame_unit_size -= obu_unit_size + len;
+
+    ret = av_bsf_send_packet(c->bsf, pkt);
+    if (ret < 0) {
+        av_log(s, AV_LOG_ERROR, "av1_frame_merge filter "
+               "failed to send input packet\n");
+        return ret;
+    }
+
+end:
+    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 receive output packet\n");
+
+    if (ret == AVERROR(EAGAIN))
+        goto retry;
+
+    return ret;
+}
+
+static int annexb_read_close(AVFormatContext *s)
+{
+    AnnexBContext *c = s->priv_data;
+
+    av_bsf_free(&c->bsf);
+    return 0;
+}
+
+#define OFFSET(x) offsetof(AnnexBContext, x)
+#define DEC AV_OPT_FLAG_DECODING_PARAM
+static const AVOption annexb_options[] = {
+    { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
+    { NULL },
+};
+
+static const AVClass annexb_demuxer_class = {
+    .class_name = "AV1 Annex-B demuxer",
+    .item_name  = av_default_item_name,
+    .option     = annexb_options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVInputFormat ff_obu_demuxer = {
+    .name           = "obu",
+    .long_name      = NULL_IF_CONFIG_SMALL("OBU"),
+    .priv_data_size = sizeof(AnnexBContext),
+    .read_probe     = annexb_probe,
+    .read_header    = annexb_read_header,
+    .read_packet    = annexb_read_packet,
+    .read_close     = annexb_read_close,
+    .extensions     = "obu",
+    .flags          = AVFMT_GENERIC_INDEX,
+    .priv_class     = &annexb_demuxer_class,
+};