[FFmpeg-devel] [PATCH V3] example/vaapi_transcode: Add a VA-API transcode example.
Jun Zhao
mypopydev at gmail.com
Mon Jan 29 04:59:58 EET 2018
V3: - Add error check when av_buffer_ref fail
- Fix exec encode/write but output file hasn't been open lead to crash issue
- Add build check
V2: - deduce output format from file extension, because VP8/VP9 encoder
need to a muxer (e,g ivf or/and mp4).
-------------- next part --------------
From 1f9dcc65093e05a0a7a931352aaa9c1e67be5d2f Mon Sep 17 00:00:00 2001
From: Jun Zhao <jun.zhao at intel.com>
Date: Thu, 11 Jan 2018 15:00:30 +0800
Subject: [PATCH V3] example/vaapi_transcode: Add a VA-API transcode example.
Add VA-API transcoding example, useage like:
./vaapi_transcode input_stream h264_vaapi output_stream,
and the example can't handle resolution change case.
test case like:
- ./vaapi_transcode input.mp4 h264_vaapi output_h264.mp4
- ./vaapi_transcode input.mp4 vp8_vaapi output_vp8.ivf
Signed-off-by: Jun Zhao <jun.zhao at intel.com>
Signed-off-by: Liu, Kaixuan <kaixuan.liu at intel.com>
---
configure | 2 +
doc/examples/Makefile | 1 +
doc/examples/vaapi_transcode.c | 305 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 308 insertions(+)
create mode 100644 doc/examples/vaapi_transcode.c
diff --git a/configure b/configure
index fcfa7aa442..c4cf32e731 100755
--- a/configure
+++ b/configure
@@ -1526,6 +1526,7 @@ EXAMPLE_LIST="
transcode_aac_example
transcoding_example
vaapi_encode_example
+ vaapi_transcode_example
"
EXTERNAL_AUTODETECT_LIBRARY_LIST="
@@ -3320,6 +3321,7 @@ scaling_video_example_deps="avutil swscale"
transcode_aac_example_deps="avcodec avformat swresample"
transcoding_example_deps="avfilter avcodec avformat avutil"
vaapi_encode_example_deps="avcodec avutil h264_vaapi_encoder"
+vaapi_transcode_example_deps="avcodec avformat avutil h264_vaapi_encoder"
# EXTRALIBS_LIST
cpu_init_extralibs="pthreads_extralibs"
diff --git a/doc/examples/Makefile b/doc/examples/Makefile
index da5af36532..928ff306b3 100644
--- a/doc/examples/Makefile
+++ b/doc/examples/Makefile
@@ -20,6 +20,7 @@ EXAMPLES-$(CONFIG_SCALING_VIDEO_EXAMPLE) += scaling_video
EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE) += transcode_aac
EXAMPLES-$(CONFIG_TRANSCODING_EXAMPLE) += transcoding
EXAMPLES-$(CONFIG_VAAPI_ENCODE_EXAMPLE) += vaapi_encode
+EXAMPLES-$(CONFIG_VAAPI_TRANSCODE_EXAMPLE) += vaapi_transcode
EXAMPLES := $(EXAMPLES-yes:%=doc/examples/%$(PROGSSUF)$(EXESUF))
EXAMPLES_G := $(EXAMPLES-yes:%=doc/examples/%$(PROGSSUF)_g$(EXESUF))
diff --git a/doc/examples/vaapi_transcode.c b/doc/examples/vaapi_transcode.c
new file mode 100644
index 0000000000..45eeef0a96
--- /dev/null
+++ b/doc/examples/vaapi_transcode.c
@@ -0,0 +1,305 @@
+/*
+ * Video Acceleration API (video transcoding) transcode sample
+ *
+ * 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
+ * Intel VAAPI-accelerated transcoding example.
+ *
+ * @example vaapi_transcode.c
+ * This example shows how to do VAAPI-accelerated transcoding.
+ * Usage: vaapi_transcode input_stream h264_vaapi output_stream
+ * e.g: - vaapi_transcode input.mp4 h264_vaapi output_h264.mp4
+ * - vaapi_transcode input.mp4 vp9_vaapi output_vp9.ivf
+ */
+
+#include <stdio.h>
+#include <errno.h>
+
+#include <libavutil/hwcontext.h>
+#include <libavcodec/avcodec.h>
+#include <libavformat/avformat.h>
+
+static AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
+static AVBufferRef *hw_device_ctx = NULL;
+static AVCodecContext *decoder_ctx = NULL, *encoder_ctx = NULL;
+static int video_stream = -1;
+static AVStream *ost;
+static int initialized = 0;
+
+static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx,
+ const enum AVPixelFormat *pix_fmts)
+{
+ const enum AVPixelFormat *p;
+
+ for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
+ if (*p == AV_PIX_FMT_VAAPI)
+ return *p;
+ }
+
+ fprintf(stderr, "Unable to decode this file using VA-API.\n");
+ return AV_PIX_FMT_NONE;
+}
+
+static int open_input_file(const char *filename)
+{
+ int ret;
+ AVCodec *decoder = NULL;
+ AVStream *video = NULL;
+
+ if ((ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL)) < 0) {
+ fprintf(stderr, "Cannot open input file '%s', Error code: %s\n",
+ filename, av_err2str(ret));
+ return ret;
+ }
+
+ if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) < 0) {
+ fprintf(stderr, "Cannot find input stream information. Error code: %s\n",
+ av_err2str(ret));
+ return ret;
+ }
+
+ ret = av_find_best_stream(ifmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot find a video stream in the input file. "
+ "Error code: %s\n", av_err2str(ret));
+ return ret;
+ }
+ video_stream = ret;
+
+ if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
+ return AVERROR(ENOMEM);
+
+ video = ifmt_ctx->streams[video_stream];
+ if ((ret = avcodec_parameters_to_context(decoder_ctx, video->codecpar)) < 0) {
+ fprintf(stderr, "avcodec_parameters_to_context error. Error code: %s\n",
+ av_err2str(ret));
+ return ret;
+ }
+
+ decoder_ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
+ if (!decoder_ctx->hw_device_ctx) {
+ fprintf(stderr, "A hardware device reference create failed.\n");
+ return AVERROR(ENOMEM);
+ }
+ decoder_ctx->get_format = get_vaapi_format;
+
+ if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0)
+ fprintf(stderr, "Failed to open codec for decoding. Error code: %s\n",
+ av_err2str(ret));
+
+ return ret;
+}
+
+static int encode_write(AVFrame *frame)
+{
+ int ret = 0;
+ AVPacket enc_pkt;
+
+ av_init_packet(&enc_pkt);
+ enc_pkt.data = NULL;
+ enc_pkt.size = 0;
+
+ if ((ret = avcodec_send_frame(encoder_ctx, frame)) < 0) {
+ fprintf(stderr, "Error during encoding. Error code: %s\n", av_err2str(ret));
+ goto end;
+ }
+ while (1) {
+ ret = avcodec_receive_packet(encoder_ctx, &enc_pkt);
+ if (ret)
+ break;
+
+ enc_pkt.stream_index = 0;
+ av_packet_rescale_ts(&enc_pkt, ifmt_ctx->streams[video_stream]->time_base,
+ ofmt_ctx->streams[0]->time_base);
+ ret = av_interleaved_write_frame(ofmt_ctx, &enc_pkt);
+ if (ret < 0) {
+ fprintf(stderr, "Error during writing data to output file. "
+ "Error code: %s\n", av_err2str(ret));
+ return -1;
+ }
+ }
+
+end:
+ if (ret == AVERROR_EOF)
+ return 0;
+ ret = ((ret == AVERROR(EAGAIN)) ? 0:-1);
+ return ret;
+}
+
+static int dec_enc(AVPacket *pkt, AVCodec *enc_codec)
+{
+ AVFrame *frame;
+ int ret = 0;
+
+ ret = avcodec_send_packet(decoder_ctx, pkt);
+ if (ret < 0) {
+ fprintf(stderr, "Error during decoding. Error code: %s\n", av_err2str(ret));
+ return ret;
+ }
+
+ while (ret >= 0) {
+ if (!(frame = av_frame_alloc()))
+ return AVERROR(ENOMEM);
+
+ ret = avcodec_receive_frame(decoder_ctx, frame);
+ if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
+ av_frame_free(&frame);
+ return 0;
+ } else if (ret < 0) {
+ fprintf(stderr, "Error while decoding. Error code: %s\n", av_err2str(ret));
+ goto fail;
+ }
+
+ if (!initialized) {
+ /* we need to ref hw_frames_ctx of decoder to initialize encoder's codec.
+ Only after we get a decoded frame, can we obtain its hw_frames_ctx */
+ encoder_ctx->hw_frames_ctx = av_buffer_ref(decoder_ctx->hw_frames_ctx);
+ if (!encoder_ctx->hw_frames_ctx) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ /* set AVCodecContext Parameters for encoder, here we keep them stay
+ * the same as decoder.
+ * xxx: now the the sample can't handle resolution change case.
+ */
+ encoder_ctx->time_base = av_inv_q(decoder_ctx->framerate);
+ encoder_ctx->pix_fmt = AV_PIX_FMT_VAAPI;
+ encoder_ctx->width = decoder_ctx->width;
+ encoder_ctx->height = decoder_ctx->height;
+
+ if ((ret = avcodec_open2(encoder_ctx, enc_codec, NULL)) < 0) {
+ fprintf(stderr, "Failed to open encode codec. Error code: %s\n",
+ av_err2str(ret));
+ goto fail;
+ }
+
+ if (!(ost = avformat_new_stream(ofmt_ctx, enc_codec))) {
+ fprintf(stderr, "Failed to allocate stream for output format.\n");
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+
+ ost->time_base = encoder_ctx->time_base;
+ ret = avcodec_parameters_from_context(ost->codecpar, encoder_ctx);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to copy the stream parameters. "
+ "Error code: %s\n", av_err2str(ret));
+ goto fail;
+ }
+
+ /* write the stream header */
+ if ((ret = avformat_write_header(ofmt_ctx, NULL)) < 0) {
+ fprintf(stderr, "Error while writing stream header. "
+ "Error code: %s\n", av_err2str(ret));
+ goto fail;
+ }
+
+ initialized = 1;
+ }
+
+ if ((ret = encode_write(frame)) < 0)
+ fprintf(stderr, "Error during encoding and writing.\n");
+
+fail:
+ av_frame_free(&frame);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+int main(int argc, char **argv) {
+ int ret = 0;
+ AVPacket dec_pkt;
+ AVCodec *enc_codec;
+
+ if (argc != 4) {
+ fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"
+ "The output format is guessed according to the file extension.\n"
+ "\n", argv[0]);
+ return -1;
+ }
+
+ av_register_all();
+
+ ret = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI, NULL, NULL, 0);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));
+ return -1;
+ }
+
+ if ((ret = open_input_file(argv[1])) < 0)
+ goto end;
+
+ if (!(enc_codec = avcodec_find_encoder_by_name(argv[2]))) {
+ fprintf(stderr, "Could not find encoder '%s'\n", argv[2]);
+ ret = -1;
+ goto end;
+ }
+
+ if ((ret = (avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, argv[3]))) < 0) {
+ fprintf(stderr, "Failed to deduce output format from file extension. Error code: "
+ "%s\n", av_err2str(ret));
+ goto end;
+ }
+
+ if (!(encoder_ctx = avcodec_alloc_context3(enc_codec))) {
+ ret = AVERROR(ENOMEM);
+ goto end;
+ }
+
+ ret = avio_open(&ofmt_ctx->pb, argv[3], AVIO_FLAG_WRITE);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot open output file. "
+ "Error code: %s\n", av_err2str(ret));
+ goto end;
+ }
+
+ /* read all packets and only transcoding video */
+ while (ret >= 0) {
+ if ((ret = av_read_frame(ifmt_ctx, &dec_pkt)) < 0)
+ break;
+
+ if (video_stream == dec_pkt.stream_index)
+ ret = dec_enc(&dec_pkt, enc_codec);
+
+ av_packet_unref(&dec_pkt);
+ }
+
+ /* flush decoder */
+ dec_pkt.data = NULL;
+ dec_pkt.size = 0;
+ ret = dec_enc(&dec_pkt, enc_codec);
+ av_packet_unref(&dec_pkt);
+
+ /* flush encoder */
+ ret = encode_write(NULL);
+
+ /* write the trailer for output stream */
+ av_write_trailer(ofmt_ctx);
+
+end:
+ avformat_close_input(&ifmt_ctx);
+ avformat_close_input(&ofmt_ctx);
+ avcodec_free_context(&decoder_ctx);
+ avcodec_free_context(&encoder_ctx);
+ av_buffer_unref(&hw_device_ctx);
+ return ret;
+}
--
2.14.1
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