[FFmpeg-devel] [PATCH] avcodec: add AV1 frame split bitstream filter
James Almer
jamrial at gmail.com
Tue Dec 18 02:56:27 EET 2018
This will be needed by the eventual native AV1 decoder.
Signed-off-by: James Almer <jamrial at gmail.com>
---
Missing Changelog entry, version bump
configure | 1 +
libavcodec/Makefile | 1 +
libavcodec/av1_frame_split_bsf.c | 246 +++++++++++++++++++++++++++++++
libavcodec/bitstream_filters.c | 1 +
4 files changed, 249 insertions(+)
create mode 100644 libavcodec/av1_frame_split_bsf.c
diff --git a/configure b/configure
index b062b6318e..16854f5418 100755
--- a/configure
+++ b/configure
@@ -3036,6 +3036,7 @@ vc1_parser_select="vc1dsp"
# bitstream_filters
aac_adtstoasc_bsf_select="adts_header"
+av1_frame_split_select="cbs_av1"
av1_metadata_bsf_select="cbs_av1"
eac3_core_bsf_select="ac3_parser"
filter_units_bsf_select="cbs"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index d53b8ff330..5d3acca45f 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1060,6 +1060,7 @@ OBJS-$(CONFIG_XMA_PARSER) += xma_parser.o
# bitstream filters
OBJS-$(CONFIG_AAC_ADTSTOASC_BSF) += aac_adtstoasc_bsf.o mpeg4audio.o
OBJS-$(CONFIG_AV1_METADATA_BSF) += av1_metadata_bsf.o
+OBJS-$(CONFIG_AV1_FRAME_SPLIT_BSF) += av1_frame_split_bsf.o
OBJS-$(CONFIG_CHOMP_BSF) += chomp_bsf.o
OBJS-$(CONFIG_DUMP_EXTRADATA_BSF) += dump_extradata_bsf.o
OBJS-$(CONFIG_DCA_CORE_BSF) += dca_core_bsf.o
diff --git a/libavcodec/av1_frame_split_bsf.c b/libavcodec/av1_frame_split_bsf.c
new file mode 100644
index 0000000000..8f4a7c3aa5
--- /dev/null
+++ b/libavcodec/av1_frame_split_bsf.c
@@ -0,0 +1,246 @@
+/*
+ * 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
+ */
+
+/**
+ * @file
+ * This bitstream filter splits AV1 Temporal Units into packets containing
+ * just one frame.
+ */
+
+#include "libavutil/avassert.h"
+#include "avcodec.h"
+#include "cbs.h"
+#include "cbs_av1.h"
+#include "bsf.h"
+
+typedef struct AV1FSplitContext {
+ AVPacket *buffer_pkt;
+ CodedBitstreamContext *cbc;
+ CodedBitstreamFragment temporal_unit;
+
+ int nb_frames;
+ int cur_frame;
+ int cur_frame_idx;
+ int last_frame_idx;
+} AV1FSplitContext;
+
+static int av1_frame_split_filter(AVBSFContext *ctx, AVPacket *out)
+{
+ AV1FSplitContext *s = ctx->priv_data;
+ CodedBitstreamFragment *td = &s->temporal_unit;
+ int i, ret;
+ int split = !!s->buffer_pkt->data;
+
+ if (!s->buffer_pkt->data) {
+ int nb_frames = 0;
+
+ ret = ff_bsf_get_packet_ref(ctx, s->buffer_pkt);
+ if (ret < 0)
+ return ret;
+
+ ret = ff_cbs_read_packet(s->cbc, td, s->buffer_pkt);
+ if (ret < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Failed to parse temporal unit.\n");
+ return ret;
+ }
+
+ for (i = 0; i < td->nb_units; i++) {
+ CodedBitstreamUnit *unit = &td->units[i];
+
+ if (unit->type == AV1_OBU_FRAME ||
+ unit->type == AV1_OBU_FRAME_HEADER)
+ nb_frames++;
+ else if (unit->type == AV1_OBU_TILE_LIST) {
+ av_log(ctx, AV_LOG_VERBOSE, "Large scale tiles are unsupported. Skipping Temporal Unit.\n");
+ break;
+ }
+ }
+ if (nb_frames > 1) {
+ s->cur_frame = 0;
+ // Don't attach the Temporal Delimiter OBU with the first frame
+ s->cur_frame_idx = s->last_frame_idx =
+ td->units[0].type == AV1_OBU_TEMPORAL_DELIMITER;
+ s->nb_frames = nb_frames;
+ split = 1;
+ }
+ }
+
+ if (split) {
+ AV1RawFrameHeader *frame = NULL;
+ int cur_frame_type = -1, size = 0;
+
+ for (i = s->cur_frame_idx; i < td->nb_units; i++) {
+ CodedBitstreamUnit *unit = &td->units[i];
+
+ size += unit->data_size;
+ if (unit->type == AV1_OBU_FRAME) {
+ AV1RawOBU *obu = unit->content;
+
+ if (frame) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ frame = &obu->obu.frame.header;
+ cur_frame_type = obu->header.obu_type;
+ s->last_frame_idx = s->cur_frame_idx;
+ s->cur_frame_idx = i + 1;
+ s->cur_frame++;
+
+ // split here unless it's the last frame, in which case
+ // include every trailing OBU
+ if (s->cur_frame < s->nb_frames)
+ break;
+ } else if (unit->type == AV1_OBU_FRAME_HEADER) {
+ AV1RawOBU *obu = unit->content;
+
+ if (frame) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ frame = &obu->obu.frame_header;
+ cur_frame_type = obu->header.obu_type;
+ s->last_frame_idx = s->cur_frame_idx;
+ s->cur_frame++;
+
+ // split here if show_existing_frame unless it's the last
+ // frame, in which case include every trailing OBU
+ if (frame->show_existing_frame &&
+ s->cur_frame < s->nb_frames) {
+ s->cur_frame_idx = i + 1;
+ break;
+ }
+ } else if (unit->type == AV1_OBU_TILE_GROUP) {
+ AV1RawOBU *obu = unit->content;
+ AV1RawTileGroup *group = &obu->obu.tile_group;
+
+ if (!frame || cur_frame_type != AV1_OBU_FRAME_HEADER) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ if ((group->tg_end == (frame->tile_cols * frame->tile_rows) - 1) &&
+ // include every trailing OBU with the last frame
+ s->cur_frame < s->nb_frames) {
+ s->cur_frame_idx = i + 1;
+ break;
+ }
+ }
+ }
+ av_assert0(frame && s->cur_frame <= s->nb_frames);
+
+ ret = av_packet_ref(out, s->buffer_pkt);
+ if (ret < 0)
+ goto fail;
+
+ out->data = (uint8_t *)td->units[s->last_frame_idx].data;
+ out->size = size;
+
+ if (!frame->show_existing_frame && !frame->show_frame)
+ out->pts = AV_NOPTS_VALUE;
+
+ if (s->cur_frame == s->nb_frames) {
+ av_packet_unref(s->buffer_pkt);
+ ff_cbs_fragment_uninit(s->cbc, td);
+ }
+ } else {
+ av_packet_move_ref(out, s->buffer_pkt);
+ ff_cbs_fragment_uninit(s->cbc, td);
+ }
+
+ return 0;
+
+fail:
+ if (ret < 0)
+ av_packet_unref(out);
+ av_packet_unref(s->buffer_pkt);
+ ff_cbs_fragment_uninit(s->cbc, td);
+
+ return ret;
+}
+
+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 int av1_frame_split_init(AVBSFContext *ctx)
+{
+ AV1FSplitContext *s = ctx->priv_data;
+ CodedBitstreamFragment *td = &s->temporal_unit;
+ int ret;
+
+ s->buffer_pkt = av_packet_alloc();
+ if (!s->buffer_pkt)
+ return AVERROR(ENOMEM);
+
+ ret = ff_cbs_init(&s->cbc, AV_CODEC_ID_AV1, ctx);
+ 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);
+
+ if (!ctx->par_in->extradata_size)
+ return 0;
+
+ ret = ff_cbs_read_extradata(s->cbc, td, ctx->par_in);
+ if (ret < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Failed to parse extradata.\n");
+ return ret;
+ }
+
+ ff_cbs_fragment_uninit(s->cbc, td);
+
+ return 0;
+}
+
+static void av1_frame_split_flush(AVBSFContext *ctx)
+{
+ AV1FSplitContext *s = ctx->priv_data;
+
+ av_packet_unref(s->buffer_pkt);
+ ff_cbs_fragment_uninit(s->cbc, &s->temporal_unit);
+}
+
+static void av1_frame_split_close(AVBSFContext *ctx)
+{
+ AV1FSplitContext *s = ctx->priv_data;
+
+ av_packet_free(&s->buffer_pkt);
+ ff_cbs_fragment_uninit(s->cbc, &s->temporal_unit);
+ ff_cbs_close(&s->cbc);
+}
+
+static const enum AVCodecID av1_frame_split_codec_ids[] = {
+ AV_CODEC_ID_AV1, AV_CODEC_ID_NONE,
+};
+
+const AVBitStreamFilter ff_av1_frame_split_bsf = {
+ .name = "av1_frame_split",
+ .priv_data_size = sizeof(AV1FSplitContext),
+ .init = av1_frame_split_init,
+ .flush = av1_frame_split_flush,
+ .close = av1_frame_split_close,
+ .filter = av1_frame_split_filter,
+ .codec_ids = av1_frame_split_codec_ids,
+};
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index 2c999d3c1d..463003966a 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -25,6 +25,7 @@
#include "bsf.h"
extern const AVBitStreamFilter ff_aac_adtstoasc_bsf;
+extern const AVBitStreamFilter ff_av1_frame_split_bsf;
extern const AVBitStreamFilter ff_av1_metadata_bsf;
extern const AVBitStreamFilter ff_chomp_bsf;
extern const AVBitStreamFilter ff_dump_extradata_bsf;
--
2.19.2
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