[FFmpeg-cvslog] lavc: add a HEVC mp4->annex B bitstream filter
Anton Khirnov
git at videolan.org
Sun Jul 26 00:42:43 CEST 2015
ffmpeg | branch: master | Anton Khirnov <anton at khirnov.net> | Thu Jul 9 11:28:38 2015 +0200| [f89f78c1c563d98f10ee1d7e1ed67c9f9e03b741] | committer: Anton Khirnov
lavc: add a HEVC mp4->annex B bitstream filter
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f89f78c1c563d98f10ee1d7e1ed67c9f9e03b741
---
Changelog | 1 +
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/hevc_mp4toannexb_bsf.c | 186 +++++++++++++++++++++++++++++++++++++
4 files changed, 189 insertions(+)
diff --git a/Changelog b/Changelog
index 99b3d1d..99e23d6 100644
--- a/Changelog
+++ b/Changelog
@@ -39,6 +39,7 @@ version <next>:
- rewritten ASF demuxer
- Go2Meeting decoding support
- Intel QSV-accelerated MPEG-2 video and HEVC encoding
+- bitstream filter for converting HEVC from MP4 to Annex B
version 11:
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 6bc9ff7..1bfd954 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -730,6 +730,7 @@ OBJS-$(CONFIG_AAC_ADTSTOASC_BSF) += aac_adtstoasc_bsf.o aacadtsdec.o \
OBJS-$(CONFIG_CHOMP_BSF) += chomp_bsf.o
OBJS-$(CONFIG_DUMP_EXTRADATA_BSF) += dump_extradata_bsf.o
OBJS-$(CONFIG_H264_MP4TOANNEXB_BSF) += h264_mp4toannexb_bsf.o
+OBJS-$(CONFIG_HEVC_MP4TOANNEXB_BSF) += hevc_mp4toannexb_bsf.o
OBJS-$(CONFIG_IMX_DUMP_HEADER_BSF) += imx_dump_header_bsf.o
OBJS-$(CONFIG_MJPEG2JPEG_BSF) += mjpeg2jpeg_bsf.o
OBJS-$(CONFIG_MJPEGA_DUMP_HEADER_BSF) += mjpega_dump_header_bsf.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 9fdbe8f..67f40bf 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -529,6 +529,7 @@ void avcodec_register_all(void)
REGISTER_BSF(CHOMP, chomp);
REGISTER_BSF(DUMP_EXTRADATA, dump_extradata);
REGISTER_BSF(H264_MP4TOANNEXB, h264_mp4toannexb);
+ REGISTER_BSF(HEVC_MP4TOANNEXB, hevc_mp4toannexb);
REGISTER_BSF(IMX_DUMP_HEADER, imx_dump_header);
REGISTER_BSF(MJPEG2JPEG, mjpeg2jpeg);
REGISTER_BSF(MJPEGA_DUMP_HEADER, mjpega_dump_header);
diff --git a/libavcodec/hevc_mp4toannexb_bsf.c b/libavcodec/hevc_mp4toannexb_bsf.c
new file mode 100644
index 0000000..449c8a3
--- /dev/null
+++ b/libavcodec/hevc_mp4toannexb_bsf.c
@@ -0,0 +1,186 @@
+/*
+ * HEVC MP4 to Annex B byte stream format filter
+ * copyright (c) 2015 Anton Khirnov
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <string.h>
+
+#include "libavutil/intreadwrite.h"
+#include "libavutil/mem.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "hevc.h"
+
+#define MIN_HEVCC_LENGTH 23
+
+typedef struct HEVCBSFContext {
+ uint8_t length_size;
+ int extradata_parsed;
+
+ int logged_nonmp4_warning;
+} HEVCBSFContext;
+
+static int hevc_extradata_to_annexb(AVCodecContext *avctx)
+{
+ GetByteContext gb;
+ int length_size, num_arrays, i, j;
+ int ret = 0;
+
+ uint8_t *new_extradata = NULL;
+ size_t new_extradata_size = 0;;
+
+ bytestream2_init(&gb, avctx->extradata, avctx->extradata_size);
+
+ bytestream2_skip(&gb, 21);
+ length_size = (bytestream2_get_byte(&gb) & 3) + 1;
+ num_arrays = bytestream2_get_byte(&gb);
+
+ for (i = 0; i < num_arrays; i++) {
+ int type = bytestream2_get_byte(&gb) & 0x3f;
+ int cnt = bytestream2_get_be16(&gb);
+
+ if (!(type == NAL_VPS || type == NAL_SPS || type == NAL_PPS ||
+ type == NAL_SEI_PREFIX || type == NAL_SEI_SUFFIX)) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid NAL unit type in extradata: %d\n",
+ type);
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ for (j = 0; j < cnt; j++) {
+ int nalu_len = bytestream2_get_be16(&gb);
+
+ if (4 + FF_INPUT_BUFFER_PADDING_SIZE + nalu_len > SIZE_MAX - new_extradata_size) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+ ret = av_reallocp(&new_extradata, new_extradata_size + nalu_len + 4 + FF_INPUT_BUFFER_PADDING_SIZE);
+ if (ret < 0)
+ goto fail;
+
+ AV_WB32(new_extradata + new_extradata_size, 1); // add the startcode
+ bytestream2_get_buffer(&gb, new_extradata + new_extradata_size + 4, nalu_len);
+ new_extradata_size += 4 + nalu_len;
+ memset(new_extradata + new_extradata_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+ }
+ }
+
+ av_freep(&avctx->extradata);
+ avctx->extradata = new_extradata;
+ avctx->extradata_size = new_extradata_size;
+
+ if (!new_extradata_size)
+ av_log(avctx, AV_LOG_WARNING, "No parameter sets in the extradata\n");
+
+ return length_size;
+fail:
+ av_freep(&new_extradata);
+ return ret;
+}
+
+static int hevc_mp4toannexb_filter(AVBitStreamFilterContext *bsfc,
+ AVCodecContext *avctx, const char *args,
+ uint8_t **poutbuf, int *poutbuf_size,
+ const uint8_t *buf, int buf_size,
+ int keyframe)
+{
+ HEVCBSFContext *ctx = bsfc->priv_data;
+ GetByteContext gb;
+
+ uint8_t *out = NULL;
+ size_t out_size = 0;
+ int got_irap = 0;
+ int i, ret = 0;
+
+ if (!ctx->extradata_parsed) {
+ if (avctx->extradata_size < MIN_HEVCC_LENGTH ||
+ AV_RB24(avctx->extradata) == 1 ||
+ AV_RB32(avctx->extradata) == 1) {
+ if (!ctx->logged_nonmp4_warning) {
+ av_log(avctx, AV_LOG_VERBOSE,
+ "The input looks like it is Annex B already\n");
+ ctx->logged_nonmp4_warning = 1;
+ }
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
+ return 0;
+ }
+
+ ret = hevc_extradata_to_annexb(avctx);
+ if (ret < 0)
+ return ret;
+ ctx->length_size = ret;
+ ctx->extradata_parsed = 1;
+ }
+
+ *poutbuf_size = 0;
+ *poutbuf = NULL;
+
+ bytestream2_init(&gb, buf, buf_size);
+
+ while (bytestream2_get_bytes_left(&gb)) {
+ uint32_t nalu_size = 0;
+ int nalu_type;
+ int is_irap, add_extradata, extra_size;
+
+ for (i = 0; i < ctx->length_size; i++)
+ nalu_size = (nalu_size << 8) | bytestream2_get_byte(&gb);
+
+ nalu_type = (bytestream2_peek_byte(&gb) >> 1) & 0x3f;
+
+ /* prepend extradata to IRAP frames */
+ is_irap = nalu_type >= 16 && nalu_type <= 23;
+ add_extradata = is_irap && !got_irap;
+ extra_size = add_extradata * avctx->extradata_size;
+ got_irap |= is_irap;
+
+ if (SIZE_MAX - out_size < 4 ||
+ SIZE_MAX - out_size - 4 < nalu_size ||
+ SIZE_MAX - out_size - 4 - nalu_size < extra_size) {
+ ret = AVERROR_INVALIDDATA;
+ goto fail;
+ }
+
+ ret = av_reallocp(&out, out_size + 4 + nalu_size + extra_size);
+ if (ret < 0)
+ goto fail;
+
+ if (add_extradata)
+ memcpy(out + out_size, avctx->extradata, extra_size);
+ AV_WB32(out + out_size + extra_size, 1);
+ bytestream2_get_buffer(&gb, out + out_size + 4 + extra_size, nalu_size);
+ out_size += 4 + nalu_size + extra_size;
+ }
+
+ *poutbuf = out;
+ *poutbuf_size = out_size;
+
+ return 1;
+
+fail:
+ av_freep(&out);
+ return ret;
+}
+
+AVBitStreamFilter ff_hevc_mp4toannexb_bsf = {
+ "hevc_mp4toannexb",
+ sizeof(HEVCBSFContext),
+ hevc_mp4toannexb_filter,
+};
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