[FFmpeg-devel] [PATCH v25 3/9] avformat/evc_demuxer: Added demuxer to handle reading EVC video files
Dawid Kozinski
d.kozinski at samsung.com
Thu Jun 15 09:24:26 EEST 2023
- Provided AVInputFormat struct describing EVC input format (ff_evc_demuxer)
Signed-off-by: Dawid Kozinski <d.kozinski at samsung.com>
---
libavcodec/Makefile | 1 +
libavcodec/bitstream_filters.c | 5 +-
libavcodec/evc_frame_merge_bsf.c | 170 +++++++++++++++++++
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/evcdec.c | 276 +++++++++++++++++++++++++++++++
6 files changed, 452 insertions(+), 2 deletions(-)
create mode 100644 libavcodec/evc_frame_merge_bsf.c
create mode 100644 libavformat/evcdec.c
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index a28919992a..0ce8fe5b9c 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1258,6 +1258,7 @@ OBJS-$(CONFIG_VP9_METADATA_BSF) += vp9_metadata_bsf.o
OBJS-$(CONFIG_VP9_RAW_REORDER_BSF) += vp9_raw_reorder_bsf.o
OBJS-$(CONFIG_VP9_SUPERFRAME_BSF) += vp9_superframe_bsf.o
OBJS-$(CONFIG_VP9_SUPERFRAME_SPLIT_BSF) += vp9_superframe_split_bsf.o
+OBJS-$(CONFIG_EVC_FRAME_MERGE_BSF) += evc_frame_merge_bsf.o
# thread libraries
OBJS-$(HAVE_LIBC_MSVCRT) += file_open.o
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index e8216819ca..7512fccc78 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -65,16 +65,17 @@ extern const FFBitStreamFilter ff_vp9_metadata_bsf;
extern const FFBitStreamFilter ff_vp9_raw_reorder_bsf;
extern const FFBitStreamFilter ff_vp9_superframe_bsf;
extern const FFBitStreamFilter ff_vp9_superframe_split_bsf;
+extern const FFBitStreamFilter ff_evc_frame_merge_bsf;
#include "libavcodec/bsf_list.c"
const AVBitStreamFilter *av_bsf_iterate(void **opaque)
{
- uintptr_t i = (uintptr_t)*opaque;
+ uintptr_t i = (uintptr_t) * opaque;
const FFBitStreamFilter *f = bitstream_filters[i];
if (f) {
- *opaque = (void*)(i + 1);
+ *opaque = (void *)(i + 1);
return &f->p;
}
return NULL;
diff --git a/libavcodec/evc_frame_merge_bsf.c b/libavcodec/evc_frame_merge_bsf.c
new file mode 100644
index 0000000000..7f52c06292
--- /dev/null
+++ b/libavcodec/evc_frame_merge_bsf.c
@@ -0,0 +1,170 @@
+/*
+ * 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 "get_bits.h"
+#include "golomb.h"
+#include "bsf.h"
+#include "bsf_internal.h"
+#include "avcodec.h"
+
+#include "evc.h"
+#include "evc_parse.h"
+
+#define INIT_AU_BUF_CAPACITY 1024
+
+// Access unit data
+typedef struct AccessUnitBuffer {
+ uint8_t *data; // the data buffer
+ size_t data_size; // size of data in bytes
+ size_t capacity; // buffer capacity
+} AccessUnitBuffer;
+
+typedef struct EVCFMergeContext {
+ AVPacket *in;
+ EVCParserContext parser_ctx;
+ AccessUnitBuffer au_buffer;
+} EVCFMergeContext;
+
+static int end_of_access_unit_found(EVCParserContext *parser_ctx)
+{
+ if (parser_ctx->profile == 0) { // BASELINE profile
+ if (parser_ctx->nalu_type == EVC_NOIDR_NUT || parser_ctx->nalu_type == EVC_IDR_NUT)
+ return 1;
+ } else { // MAIN profile
+ if (parser_ctx->nalu_type == EVC_NOIDR_NUT) {
+ if (parser_ctx->poc.PicOrderCntVal != parser_ctx->poc.prevPicOrderCntVal)
+ return 1;
+ } else if (parser_ctx->nalu_type == EVC_IDR_NUT)
+ return 1;
+ }
+ return 0;
+}
+
+static void evc_frame_merge_flush(AVBSFContext *bsf)
+{
+ EVCFMergeContext *ctx = bsf->priv_data;
+
+ av_packet_unref(ctx->in);
+}
+
+static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
+{
+ EVCFMergeContext *ctx = bsf->priv_data;
+ EVCParserContext *parser_ctx = &ctx->parser_ctx;
+
+ AVPacket *in = ctx->in;
+
+ int free_space = 0;
+ size_t nalu_size = 0;
+ uint8_t *nalu = NULL;
+ int au_end_found = 0;
+ int err;
+
+ err = ff_bsf_get_packet_ref(bsf, in);
+ if (err < 0)
+ return err;
+
+ nalu_size = ff_evc_read_nal_unit_length(in->data, EVC_NALU_LENGTH_PREFIX_SIZE, bsf);
+ if (nalu_size <= 0) {
+ av_packet_unref(in);
+ return AVERROR_INVALIDDATA;
+ }
+
+ nalu = in->data + EVC_NALU_LENGTH_PREFIX_SIZE;
+ nalu_size = in->size - EVC_NALU_LENGTH_PREFIX_SIZE;
+
+ // NAL unit parsing needed to determine if end of AU was found
+ err = ff_evc_parse_nal_unit(parser_ctx, nalu, nalu_size, bsf);
+ if (err < 0) {
+ av_log(bsf, AV_LOG_ERROR, "NAL Unit parsing error\n");
+ av_packet_unref(in);
+
+ return err;
+ }
+
+ au_end_found = end_of_access_unit_found(parser_ctx);
+
+ free_space = ctx->au_buffer.capacity - ctx->au_buffer.data_size;
+ while (free_space < in->size) {
+ ctx->au_buffer.capacity *= 2;
+ free_space = ctx->au_buffer.capacity - ctx->au_buffer.data_size;
+
+ if (free_space >= in->size)
+ ctx->au_buffer.data = av_realloc(ctx->au_buffer.data, ctx->au_buffer.capacity);
+ }
+
+ memcpy(ctx->au_buffer.data + ctx->au_buffer.data_size, in->data, in->size);
+
+ ctx->au_buffer.data_size += in->size;
+
+ av_packet_unref(in);
+
+ if (au_end_found) {
+ uint8_t *data = av_memdup(ctx->au_buffer.data, ctx->au_buffer.data_size);
+ err = av_packet_from_data(out, data, ctx->au_buffer.data_size);
+
+ ctx->au_buffer.data_size = 0;
+ } else
+ err = AVERROR(EAGAIN);
+
+ if (err < 0 && err != AVERROR(EAGAIN))
+ evc_frame_merge_flush(bsf);
+
+ return err;
+}
+
+static int evc_frame_merge_init(AVBSFContext *bsf)
+{
+ EVCFMergeContext *ctx = bsf->priv_data;
+
+ ctx->in = av_packet_alloc();
+ if (!ctx->in)
+ return AVERROR(ENOMEM);
+
+ ctx->au_buffer.capacity = INIT_AU_BUF_CAPACITY;
+ ctx->au_buffer.data = av_malloc(INIT_AU_BUF_CAPACITY);
+ ctx->au_buffer.data_size = 0;
+
+ return 0;
+}
+
+static void evc_frame_merge_close(AVBSFContext *bsf)
+{
+ EVCFMergeContext *ctx = bsf->priv_data;
+
+ av_packet_free(&ctx->in);
+
+ ctx->au_buffer.capacity = 0;
+ av_freep(&ctx->au_buffer.data);
+ ctx->au_buffer.data_size = 0;
+}
+
+static const enum AVCodecID evc_frame_merge_codec_ids[] = {
+ AV_CODEC_ID_EVC, AV_CODEC_ID_NONE,
+};
+
+const FFBitStreamFilter ff_evc_frame_merge_bsf = {
+ .p.name = "evc_frame_merge",
+ .p.codec_ids = evc_frame_merge_codec_ids,
+ .priv_data_size = sizeof(EVCFMergeContext),
+ .init = evc_frame_merge_init,
+ .flush = evc_frame_merge_flush,
+ .close = evc_frame_merge_close,
+ .filter = evc_frame_merge_filter,
+};
diff --git a/libavformat/Makefile b/libavformat/Makefile
index f31135d806..6e4231fda2 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -251,6 +251,7 @@ OBJS-$(CONFIG_HCOM_DEMUXER) += hcom.o pcm.o
OBJS-$(CONFIG_HDS_MUXER) += hdsenc.o
OBJS-$(CONFIG_HEVC_DEMUXER) += hevcdec.o rawdec.o
OBJS-$(CONFIG_HEVC_MUXER) += rawenc.o
+OBJS-$(CONFIG_EVC_DEMUXER) += evcdec.o rawdec.o
OBJS-$(CONFIG_EVC_MUXER) += rawenc.o
OBJS-$(CONFIG_HLS_DEMUXER) += hls.o hls_sample_encryption.o
OBJS-$(CONFIG_HLS_MUXER) += hlsenc.o hlsplaylist.o avc.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index d3871de268..ae604236ae 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -154,6 +154,7 @@ extern const AVInputFormat ff_ea_cdata_demuxer;
extern const AVInputFormat ff_eac3_demuxer;
extern const FFOutputFormat ff_eac3_muxer;
extern const AVInputFormat ff_epaf_demuxer;
+extern const AVInputFormat ff_evc_demuxer;
extern const FFOutputFormat ff_evc_muxer;
extern const FFOutputFormat ff_f4v_muxer;
extern const AVInputFormat ff_ffmetadata_demuxer;
diff --git a/libavformat/evcdec.c b/libavformat/evcdec.c
new file mode 100644
index 0000000000..89eda0f53e
--- /dev/null
+++ b/libavformat/evcdec.c
@@ -0,0 +1,276 @@
+/*
+ * RAW EVC video demuxer
+ *
+ * Copyright (c) 2021 Dawid Kozinski <d.kozinski at samsung.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 "libavcodec/get_bits.h"
+#include "libavcodec/golomb.h"
+#include "libavcodec/internal.h"
+#include "libavcodec/evc.h"
+#include "libavcodec/bsf.h"
+
+#include "libavutil/opt.h"
+
+#include "rawdec.h"
+#include "avformat.h"
+#include "internal.h"
+
+
+#define RAW_PACKET_SIZE 1024
+
+typedef struct EVCParserContext {
+ int got_sps;
+ int got_pps;
+ int got_idr;
+ int got_nonidr;
+
+} EVCParserContext;
+
+typedef struct EVCDemuxContext {
+ const AVClass *class;
+ AVRational framerate;
+
+ AVBSFContext *bsf;
+
+} EVCDemuxContext;
+
+#define DEC AV_OPT_FLAG_DECODING_PARAM
+#define OFFSET(x) offsetof(EVCDemuxContext, x)
+static const AVOption evc_options[] = {
+ { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
+ { NULL },
+};
+#undef OFFSET
+
+static const AVClass evc_demuxer_class = {
+ .class_name = "EVC Annex B demuxer",
+ .item_name = av_default_item_name,
+ .option = evc_options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+static int get_nalu_type(const uint8_t *bits, int bits_size)
+{
+ int unit_type_plus1 = 0;
+
+ if (bits_size >= EVC_NALU_HEADER_SIZE) {
+ unsigned char *p = (unsigned char *)bits;
+ // forbidden_zero_bit
+ if ((p[0] & 0x80) != 0) // Cannot get bitstream information. Malformed bitstream.
+ return -1;
+
+ // nal_unit_type
+ unit_type_plus1 = (p[0] >> 1) & 0x3F;
+ }
+
+ return unit_type_plus1 - 1;
+}
+
+static uint32_t read_nal_unit_length(const uint8_t *bits, int bits_size)
+{
+ uint32_t nalu_len = 0;
+
+ if (bits_size >= EVC_NALU_LENGTH_PREFIX_SIZE) {
+
+ int t = 0;
+ unsigned char *p = (unsigned char *)bits;
+
+ for (int i = 0; i < EVC_NALU_LENGTH_PREFIX_SIZE; i++)
+ t = (t << 8) | p[i];
+
+ nalu_len = t;
+ if (nalu_len == 0) // Invalid bitstream size
+ return 0;
+ }
+
+ return nalu_len;
+}
+
+static int parse_nal_units(const AVProbeData *p, EVCParserContext *ev)
+{
+ int nalu_type;
+ size_t nalu_size;
+ unsigned char *bits = (unsigned char *)p->buf;
+ int bytes_to_read = p->buf_size;
+
+ while (bytes_to_read > EVC_NALU_LENGTH_PREFIX_SIZE) {
+
+ nalu_size = read_nal_unit_length(bits, EVC_NALU_LENGTH_PREFIX_SIZE);
+ if (nalu_size == 0) break;
+
+ bits += EVC_NALU_LENGTH_PREFIX_SIZE;
+ bytes_to_read -= EVC_NALU_LENGTH_PREFIX_SIZE;
+
+ if(bytes_to_read < nalu_size) break;
+
+ nalu_type = get_nalu_type(bits, bytes_to_read);
+
+ if (nalu_type == EVC_SPS_NUT)
+ ev->got_sps++;
+ else if (nalu_type == EVC_PPS_NUT)
+ ev->got_pps++;
+ else if (nalu_type == EVC_IDR_NUT )
+ ev->got_idr++;
+ else if (nalu_type == EVC_NOIDR_NUT)
+ ev->got_nonidr++;
+
+ bits += nalu_size;
+ bytes_to_read -= nalu_size;
+ }
+
+ return 0;
+}
+
+static int annexb_probe(const AVProbeData *p)
+{
+ EVCParserContext ev = {0};
+ int ret = parse_nal_units(p, &ev);
+
+ if (ret == 0 && ev.got_sps && ev.got_pps && (ev.got_idr || ev.got_nonidr > 3))
+ return AVPROBE_SCORE_EXTENSION + 1; // 1 more than .mpg
+
+ return 0;
+}
+
+static int evc_read_header(AVFormatContext *s)
+{
+ AVStream *st;
+ FFStream *sti;
+ const AVBitStreamFilter *filter = av_bsf_get_by_name("evc_frame_merge");
+ EVCDemuxContext *c = s->priv_data;
+ int ret = 0;
+
+ st = avformat_new_stream(s, NULL);
+ if (!st) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ sti = ffstream(st);
+
+ st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+ st->codecpar->codec_id = AV_CODEC_ID_EVC;
+
+ // This causes sending to the parser full frames, not chunks of data
+ // The flag PARSER_FLAG_COMPLETE_FRAMES will be set in demux.c (demux.c: 1316)
+ sti->need_parsing = AVSTREAM_PARSE_HEADERS;
+
+ st->avg_frame_rate = c->framerate;
+ st->codecpar->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)
+ return ret;
+
+ ret = av_bsf_init(c->bsf);
+ if (ret < 0)
+ return ret;
+
+fail:
+ return ret;
+}
+
+static int evc_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ int ret;
+ int32_t nalu_size;
+ int au_end_found;
+
+ EVCDemuxContext *const c = s->priv_data;
+
+ int eof = avio_feof (s->pb);
+ if(eof) {
+ av_packet_unref(pkt);
+ return AVERROR_EOF;
+ }
+
+ au_end_found = 0;
+
+ while(!au_end_found) {
+
+ uint8_t buf[EVC_NALU_LENGTH_PREFIX_SIZE];
+ ret = avio_read(s->pb, (unsigned char *)&buf, EVC_NALU_LENGTH_PREFIX_SIZE);
+ if (ret < 0) {
+ av_packet_unref(pkt);
+ return ret;
+ }
+
+ nalu_size = read_nal_unit_length((const uint8_t *)&buf, EVC_NALU_LENGTH_PREFIX_SIZE);
+ if(nalu_size <= 0) {
+ av_packet_unref(pkt);
+ return -1;
+ }
+
+ avio_seek(s->pb, -EVC_NALU_LENGTH_PREFIX_SIZE, SEEK_CUR);
+
+ ret = av_get_packet(s->pb, pkt, nalu_size + EVC_NALU_LENGTH_PREFIX_SIZE);
+ if (ret < 0)
+ return ret;
+ if (ret != (nalu_size + EVC_NALU_LENGTH_PREFIX_SIZE))
+ return AVERROR(EIO);
+
+ ret = av_bsf_send_packet(c->bsf, pkt);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR, "Failed to send packet to "
+ "evc_frame_merge filter\n");
+ return ret;
+ }
+
+ ret = av_bsf_receive_packet(c->bsf, pkt);
+ if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF)
+ av_log(s, AV_LOG_ERROR, "evc_frame_merge filter failed to "
+ "send output packet\n");
+
+ au_end_found = 1;
+ if (ret == AVERROR(EAGAIN))
+ au_end_found = 0;
+ }
+
+ return ret;
+}
+
+static int evc_read_close(AVFormatContext *s)
+{
+ EVCDemuxContext *const c = s->priv_data;
+
+ av_bsf_free(&c->bsf);
+ return 0;
+}
+
+const AVInputFormat ff_evc_demuxer = {
+ .name = "evc",
+ .long_name = NULL_IF_CONFIG_SMALL("EVC Annex B"),
+ .read_probe = annexb_probe,
+ .read_header = evc_read_header, // annexb_read_header
+ .read_packet = evc_read_packet, // annexb_read_packet
+ .read_close = evc_read_close,
+ .extensions = "evc",
+ .flags = AVFMT_GENERIC_INDEX,
+ .flags_internal = FF_FMT_INIT_CLEANUP,
+ .raw_codec_id = AV_CODEC_ID_EVC,
+ .priv_data_size = sizeof(EVCDemuxContext),
+ .priv_class = &evc_demuxer_class,
+};
--
2.25.1
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