[FFmpeg-devel] [PATCH 2/5 v4] avcodec: add an AV1 frame merge bitstream filter
James Almer
jamrial at gmail.com
Tue Nov 12 20:30:16 EET 2019
Signed-off-by: James Almer <jamrial at gmail.com>
---
Now using an index to swap fragments.
I noticed that the input packet containing props is not necessarily the first
in a TU, so adapted the code accordingly. This fixes warnings about missing
timestamps when trying to merge the output of av1_frame_split, where the source
had the visible frames at the end of a TU rather than at the beginning.
Not going to bother with indexes for the packets. av_packet_move_ref() is far
from expensive, unlike creating buffer references and expanding the fragment's
unit buffer.
configure | 1 +
libavcodec/Makefile | 1 +
libavcodec/av1_frame_merge_bsf.c | 169 +++++++++++++++++++++++++++++++
libavcodec/bitstream_filters.c | 1 +
4 files changed, 172 insertions(+)
create mode 100644 libavcodec/av1_frame_merge_bsf.c
diff --git a/configure b/configure
index 1de90e93fd..70f60997c1 100755
--- a/configure
+++ b/configure
@@ -3115,6 +3115,7 @@ vc1_parser_select="vc1dsp"
# bitstream_filters
aac_adtstoasc_bsf_select="adts_header"
+av1_frame_merge_bsf_select="cbs_av1"
av1_frame_split_bsf_select="cbs_av1"
av1_metadata_bsf_select="cbs_av1"
eac3_core_bsf_select="ac3_parser"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b990c6ba87..006a472a6d 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1075,6 +1075,7 @@ 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_MERGE_BSF) += av1_frame_merge_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
diff --git a/libavcodec/av1_frame_merge_bsf.c b/libavcodec/av1_frame_merge_bsf.c
new file mode 100644
index 0000000000..96a9e6e863
--- /dev/null
+++ b/libavcodec/av1_frame_merge_bsf.c
@@ -0,0 +1,169 @@
+/*
+ * 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 "avcodec.h"
+#include "bsf.h"
+#include "cbs.h"
+#include "cbs_av1.h"
+
+typedef struct AV1FMergeContext {
+ CodedBitstreamContext *cbc;
+ CodedBitstreamFragment frag[2];
+ AVPacket *pkt, *in;
+ int idx;
+} AV1FMergeContext;
+
+static int av1_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
+{
+ AV1FMergeContext *ctx = bsf->priv_data;
+ CodedBitstreamFragment *frag = &ctx->frag[ctx->idx], *tu = &ctx->frag[!ctx->idx];
+ AVPacket *in = ctx->in, *buffer_pkt = ctx->pkt;
+ int err, i;
+
+ err = ff_bsf_get_packet_ref(bsf, in);
+ if (err < 0) {
+ if (err == AVERROR_EOF && tu->nb_units > 0)
+ goto eof;
+ return err;
+ }
+
+ err = ff_cbs_read_packet(ctx->cbc, frag, in);
+ if (err < 0) {
+ av_log(bsf, AV_LOG_ERROR, "Failed to read packet.\n");
+ goto fail;
+ }
+
+ if (frag->nb_units == 0) {
+ av_log(bsf, AV_LOG_ERROR, "No OBU in packet.\n");
+ err = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ if (tu->nb_units == 0 && frag->units[0].type != AV1_OBU_TEMPORAL_DELIMITER) {
+ av_log(bsf, AV_LOG_ERROR, "Missing Temporal Delimiter.\n");
+ err = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ if (tu->nb_units > 0 && frag->units[0].type == AV1_OBU_TEMPORAL_DELIMITER) {
+eof:
+ err = ff_cbs_write_packet(ctx->cbc, buffer_pkt, tu);
+ if (err < 0) {
+ av_log(bsf, AV_LOG_ERROR, "Failed to write packet.\n");
+ goto fail;
+ }
+ av_packet_move_ref(out, buffer_pkt);
+
+ ff_cbs_fragment_reset(ctx->cbc, tu);
+
+ for (i = 1; i < frag->nb_units; i++) {
+ if (frag->units[i].type == AV1_OBU_TEMPORAL_DELIMITER) {
+ av_log(bsf, AV_LOG_ERROR, "Temporal Delimiter in the middle of a packet.\n");
+ err = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+ }
+ // Swap fragment index, to avoid copying fragment references.
+ ctx->idx = !ctx->idx;
+
+ // Buffer the packet if it has a timestamp.
+ if (in->pts != AV_NOPTS_VALUE)
+ av_packet_move_ref(buffer_pkt, in);
+ av_packet_unref(in);
+
+ return 0;
+ }
+
+ // Buffer packets with timestamps. There should be at most one per TU, be it split or not.
+ if (!buffer_pkt->data && in->pts != AV_NOPTS_VALUE)
+ av_packet_move_ref(buffer_pkt, in);
+
+ for (i = 0; i < frag->nb_units; i++) {
+ if (i && frag->units[i].type == AV1_OBU_TEMPORAL_DELIMITER) {
+ av_log(bsf, AV_LOG_ERROR, "Temporal Delimiter in the middle of a packet.\n");
+ err = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+ err = ff_cbs_insert_unit_content(ctx->cbc, tu, -1, frag->units[i].type,
+ frag->units[i].content, frag->units[i].content_ref);
+ if (err < 0)
+ goto fail;
+ }
+ ff_cbs_fragment_reset(ctx->cbc, frag);
+ av_packet_unref(in);
+
+ return AVERROR(EAGAIN);
+
+fail:
+ ff_cbs_fragment_reset(ctx->cbc, tu);
+ ff_cbs_fragment_reset(ctx->cbc, frag);
+ av_packet_unref(buffer_pkt);
+ av_packet_unref(in);
+ av_packet_unref(out);
+
+ return err;
+}
+
+static int av1_frame_merge_init(AVBSFContext *bsf)
+{
+ AV1FMergeContext *ctx = bsf->priv_data;
+
+ ctx->in = av_packet_alloc();
+ ctx->pkt = av_packet_alloc();
+ if (!ctx->in || !ctx->pkt)
+ return AVERROR(ENOMEM);
+
+ return ff_cbs_init(&ctx->cbc, AV_CODEC_ID_AV1, bsf);
+}
+
+static void av1_frame_merge_flush(AVBSFContext *bsf)
+{
+ AV1FMergeContext *ctx = bsf->priv_data;
+
+ ff_cbs_fragment_reset(ctx->cbc, &ctx->frag[0]);
+ ff_cbs_fragment_reset(ctx->cbc, &ctx->frag[1]);
+ av_packet_unref(ctx->in);
+ av_packet_unref(ctx->pkt);
+}
+
+static void av1_frame_merge_close(AVBSFContext *bsf)
+{
+ AV1FMergeContext *ctx = bsf->priv_data;
+
+ ff_cbs_fragment_free(ctx->cbc, &ctx->frag[0]);
+ ff_cbs_fragment_free(ctx->cbc, &ctx->frag[1]);
+ av_packet_free(&ctx->in);
+ av_packet_free(&ctx->pkt);
+ ff_cbs_close(&ctx->cbc);
+}
+
+static const enum AVCodecID av1_frame_merge_codec_ids[] = {
+ AV_CODEC_ID_AV1, AV_CODEC_ID_NONE,
+};
+
+const AVBitStreamFilter ff_av1_frame_merge_bsf = {
+ .name = "av1_frame_merge",
+ .priv_data_size = sizeof(AV1FMergeContext),
+ .init = av1_frame_merge_init,
+ .flush = av1_frame_merge_flush,
+ .close = av1_frame_merge_close,
+ .filter = av1_frame_merge_filter,
+ .codec_ids = av1_frame_merge_codec_ids,
+};
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index 463003966a..6b5ffe4d70 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_merge_bsf;
extern const AVBitStreamFilter ff_av1_frame_split_bsf;
extern const AVBitStreamFilter ff_av1_metadata_bsf;
extern const AVBitStreamFilter ff_chomp_bsf;
--
2.23.0
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