[FFmpeg-devel] [PATCH] avcodec: add an AV1 parser
James Almer
jamrial at gmail.com
Mon Sep 24 03:12:30 EEST 2018
Simple parser to set keyframes, frame type, structure, width, height, and pixel
format, plus stream profile and level.
Signed-off-by: James Almer <jamrial at gmail.com>
---
Missing Changelog entry and version bump.
This depends on "[PATCH v2 2/3] lavc: Add coded bitstream read/write support
for AV1" which should be committed in the coming days.
The AVCodecParser.split() implementation, added for the sake of completeness,
is very naive and much like the h264 and hevc ones can result in useless OBUs
being "extracted", but since it's no longer used by libavformat to fill global
headers when reading raw containers it shouldn't really matter. It's pretty
much used only by the remove_extradata bsf at this point.
configure | 1 +
libavcodec/Makefile | 1 +
libavcodec/av1_parser.c | 218 ++++++++++++++++++++++++++++++++++++++++
libavcodec/parsers.c | 1 +
4 files changed, 221 insertions(+)
create mode 100644 libavcodec/av1_parser.c
diff --git a/configure b/configure
index ca8b599b63..b46c86ec95 100755
--- a/configure
+++ b/configure
@@ -3020,6 +3020,7 @@ wmv3_crystalhd_decoder_select="crystalhd"
# parsers
aac_parser_select="adts_header"
+av1_parser_select="cbs_av1"
h264_parser_select="golomb h264dsp h264parse"
hevc_parser_select="hevcparse"
mpegaudio_parser_select="mpegaudioheader"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b2c6995f9a..dc28892e64 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1006,6 +1006,7 @@ OBJS-$(CONFIG_AAC_PARSER) += aac_parser.o aac_ac3_parser.o \
mpeg4audio.o
OBJS-$(CONFIG_AC3_PARSER) += ac3tab.o aac_ac3_parser.o
OBJS-$(CONFIG_ADX_PARSER) += adx_parser.o adx.o
+OBJS-$(CONFIG_AV1_PARSER) += av1_parser.o
OBJS-$(CONFIG_AVS2_PARSER) += avs2_parser.o
OBJS-$(CONFIG_BMP_PARSER) += bmp_parser.o
OBJS-$(CONFIG_CAVSVIDEO_PARSER) += cavs_parser.o
diff --git a/libavcodec/av1_parser.c b/libavcodec/av1_parser.c
new file mode 100644
index 0000000000..b2e19e2119
--- /dev/null
+++ b/libavcodec/av1_parser.c
@@ -0,0 +1,218 @@
+/*
+ * AV1 parser
+ *
+ * Copyright (C) 2018 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 "av1_parse.h"
+#include "cbs.h"
+#include "cbs_av1.h"
+#include "parser.h"
+
+typedef struct AV1ParseContext {
+ CodedBitstreamContext *cbc;
+ CodedBitstreamFragment temporal_unit;
+ int parsed_extradata;
+} AV1ParseContext;
+
+static int av1_parser_parse(AVCodecParserContext *ctx,
+ AVCodecContext *avctx,
+ const uint8_t **out_data, int *out_size,
+ const uint8_t *data, int size)
+{
+ AV1ParseContext *s = ctx->priv_data;
+ CodedBitstreamFragment *td = &s->temporal_unit;
+ CodedBitstreamAV1Context *av1 = s->cbc->priv_data;
+ int ret;
+
+ *out_data = data;
+ *out_size = size;
+
+ ctx->key_frame = -1;
+ ctx->pict_type = AV_PICTURE_TYPE_NONE;
+ ctx->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
+
+ if (avctx->extradata_size && !s->parsed_extradata) {
+ ret = ff_cbs_read(s->cbc, td, avctx->extradata, avctx->extradata_size);
+ if (ret < 0) {
+ av_log(avctx, AV_LOG_ERROR, "Failed to parse extradata.\n");
+ return size;
+ }
+
+ s->parsed_extradata = 1;
+
+ ff_cbs_fragment_uninit(s->cbc, td);
+ }
+
+ ret = ff_cbs_read(s->cbc, td, data, size);
+ if (ret < 0) {
+ av_log(avctx, AV_LOG_ERROR, "Failed to parse temporal unit.\n");
+ return size;
+ }
+
+ if (!av1->sequence_header) {
+ av_log(avctx, AV_LOG_ERROR, "No sequence header available\n");
+ goto end;
+ }
+
+ for (int i = 0; i < td->nb_units; i++) {
+ CodedBitstreamUnit *unit = &td->units[i];
+ AV1RawOBU *obu = unit->content;
+ AV1RawSequenceHeader *seq = av1->sequence_header;
+ AV1RawFrameHeader *frame;
+ int frame_type, bitdepth, subsampling;
+
+ if (unit->type == AV1_OBU_FRAME)
+ frame = &obu->obu.frame.header;
+ else if (unit->type == AV1_OBU_FRAME_HEADER)
+ frame = &obu->obu.frame_header;
+ else
+ continue;
+
+ if (frame->show_existing_frame) {
+ AV1ReferenceFrameState *ref = &av1->ref[frame->frame_to_show_map_idx];
+
+ if (!ref->valid) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid reference frame\n");
+ goto end;
+ }
+
+ ctx->width = ref->frame_width;
+ ctx->height = ref->frame_height;
+ frame_type = ref->frame_type;
+
+ ctx->key_frame = 0;
+ } else if (!frame->show_frame) {
+ continue;
+ } else {
+ ctx->width = av1->frame_width;
+ ctx->height = av1->frame_height;
+ frame_type = frame->frame_type;
+
+ ctx->key_frame = frame_type == AV1_FRAME_KEY;
+ }
+
+ avctx->profile = seq->seq_profile;
+ avctx->level = seq->seq_level_idx[0];
+
+ switch (frame_type) {
+ case AV1_FRAME_KEY:
+ case AV1_FRAME_INTRA_ONLY:
+ ctx->pict_type = AV_PICTURE_TYPE_I;
+ break;
+ case AV1_FRAME_INTER:
+ ctx->pict_type = AV_PICTURE_TYPE_P;
+ break;
+ case AV1_FRAME_SWITCH:
+ ctx->pict_type = AV_PICTURE_TYPE_SP;
+ break;
+ }
+
+ ctx->picture_structure = AV_PICTURE_STRUCTURE_FRAME;
+
+ subsampling = seq->color_config.subsampling_x << 1 & seq->color_config.subsampling_y;
+ bitdepth = 8 + seq->color_config.high_bitdepth * 2 + seq->color_config.twelve_bit * 2;
+ switch (bitdepth) {
+ case 8:
+ if (subsampling == 3) ctx->format = seq->color_config.mono_chrome ? AV_PIX_FMT_GRAY8 :
+ AV_PIX_FMT_YUV420P;
+ else if (subsampling == 2) ctx->format = AV_PIX_FMT_YUV422P;
+ else ctx->format = AV_PIX_FMT_YUV444P;
+ break;
+ case 10:
+ if (subsampling == 3) ctx->format = seq->color_config.mono_chrome ? AV_PIX_FMT_GRAY10 :
+ AV_PIX_FMT_YUV420P10;
+ else if (subsampling == 2) ctx->format = AV_PIX_FMT_YUV422P10;
+ else ctx->format = AV_PIX_FMT_YUV444P10;
+ break;
+ case 12:
+ if (subsampling == 3) ctx->format = seq->color_config.mono_chrome ? AV_PIX_FMT_GRAY12 :
+ AV_PIX_FMT_YUV420P12;
+ else if (subsampling == 2) ctx->format = AV_PIX_FMT_YUV422P12;
+ else ctx->format = AV_PIX_FMT_YUV444P12;
+ break;
+ }
+ }
+
+end:
+ ff_cbs_fragment_uninit(s->cbc, td);
+
+ return size;
+}
+
+static const CodedBitstreamUnitType decompose_unit_types[] = {
+ AV1_OBU_TEMPORAL_DELIMITER,
+ AV1_OBU_SEQUENCE_HEADER,
+ AV1_OBU_FRAME_HEADER,
+ AV1_OBU_TILE_GROUP,
+ AV1_OBU_FRAME,
+};
+
+static av_cold int av1_parser_init(AVCodecParserContext *ctx)
+{
+ AV1ParseContext *s = ctx->priv_data;
+ int ret;
+
+ ret = ff_cbs_init(&s->cbc, AV_CODEC_ID_AV1, NULL);
+ if (ret < 0)
+ return ret;
+
+ s->cbc->decompose_unit_types = (CodedBitstreamUnitType *)decompose_unit_types;
+ s->cbc->nb_decompose_unit_types = FF_ARRAY_ELEMS(decompose_unit_types);
+
+ return 0;
+}
+
+static void av1_parser_close(AVCodecParserContext *ctx)
+{
+ AV1ParseContext *s = ctx->priv_data;
+
+ ff_cbs_close(&s->cbc);
+}
+
+static int av1_parser_split(AVCodecContext *avctx,
+ const uint8_t *buf, int buf_size)
+{
+ AV1OBU obu;
+ const uint8_t *ptr = buf, *end = buf + buf_size;
+
+ while (ptr < end) {
+ int len = ff_av1_extract_obu(&obu, ptr, buf_size, avctx);
+ if (len < 0)
+ break;
+
+ if (obu.type == AV1_OBU_FRAME_HEADER ||
+ obu.type == AV1_OBU_FRAME) {
+ return ptr - buf;
+ }
+ ptr += len;
+ buf_size -= len;
+ }
+
+ return 0;
+}
+
+AVCodecParser ff_av1_parser = {
+ .codec_ids = { AV_CODEC_ID_AV1 },
+ .priv_data_size = sizeof(AV1ParseContext),
+ .parser_init = av1_parser_init,
+ .parser_close = av1_parser_close,
+ .parser_parse = av1_parser_parse,
+ .split = av1_parser_split,
+};
diff --git a/libavcodec/parsers.c b/libavcodec/parsers.c
index cb86cceecc..f01cad4c84 100644
--- a/libavcodec/parsers.c
+++ b/libavcodec/parsers.c
@@ -26,6 +26,7 @@ extern AVCodecParser ff_aac_parser;
extern AVCodecParser ff_aac_latm_parser;
extern AVCodecParser ff_ac3_parser;
extern AVCodecParser ff_adx_parser;
+extern AVCodecParser ff_av1_parser;
extern AVCodecParser ff_avs2_parser;
extern AVCodecParser ff_bmp_parser;
extern AVCodecParser ff_cavsvideo_parser;
--
2.19.0
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