[FFmpeg-devel] [PATCH 5/5] avformat: add an AV1 Annex B demuxer
James Almer
jamrial at gmail.com
Mon Nov 11 15:36:15 EET 2019
Signed-off-by: James Almer <jamrial at 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 at 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,
+};
--
2.23.0
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