FFmpeg
vaapi_transcode.c
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1 /*
2  * Video Acceleration API (video transcoding) transcode sample
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to deal
6  * in the Software without restriction, including without limitation the rights
7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8  * copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20  * THE SOFTWARE.
21  */
22 
23 /**
24  * @file
25  * Intel VAAPI-accelerated transcoding example.
26  *
27  * @example vaapi_transcode.c
28  * This example shows how to do VAAPI-accelerated transcoding.
29  * Usage: vaapi_transcode input_stream codec output_stream
30  * e.g: - vaapi_transcode input.mp4 h264_vaapi output_h264.mp4
31  * - vaapi_transcode input.mp4 vp9_vaapi output_vp9.ivf
32  */
33 
34 #include <stdio.h>
35 #include <errno.h>
36 
37 #include <libavutil/hwcontext.h>
38 #include <libavcodec/avcodec.h>
39 #include <libavformat/avformat.h>
40 
44 static int video_stream = -1;
45 static AVStream *ost;
46 static int initialized = 0;
47 
49  const enum AVPixelFormat *pix_fmts)
50 {
51  const enum AVPixelFormat *p;
52 
53  for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
54  if (*p == AV_PIX_FMT_VAAPI)
55  return *p;
56  }
57 
58  fprintf(stderr, "Unable to decode this file using VA-API.\n");
59  return AV_PIX_FMT_NONE;
60 }
61 
62 static int open_input_file(const char *filename)
63 {
64  int ret;
65  AVCodec *decoder = NULL;
66  AVStream *video = NULL;
67 
68  if ((ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL)) < 0) {
69  fprintf(stderr, "Cannot open input file '%s', Error code: %s\n",
70  filename, av_err2str(ret));
71  return ret;
72  }
73 
75  fprintf(stderr, "Cannot find input stream information. Error code: %s\n",
76  av_err2str(ret));
77  return ret;
78  }
79 
81  if (ret < 0) {
82  fprintf(stderr, "Cannot find a video stream in the input file. "
83  "Error code: %s\n", av_err2str(ret));
84  return ret;
85  }
86  video_stream = ret;
87 
89  return AVERROR(ENOMEM);
90 
92  if ((ret = avcodec_parameters_to_context(decoder_ctx, video->codecpar)) < 0) {
93  fprintf(stderr, "avcodec_parameters_to_context error. Error code: %s\n",
94  av_err2str(ret));
95  return ret;
96  }
97 
99  if (!decoder_ctx->hw_device_ctx) {
100  fprintf(stderr, "A hardware device reference create failed.\n");
101  return AVERROR(ENOMEM);
102  }
104 
105  if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0)
106  fprintf(stderr, "Failed to open codec for decoding. Error code: %s\n",
107  av_err2str(ret));
108 
109  return ret;
110 }
111 
113 {
114  int ret = 0;
115  AVPacket enc_pkt;
116 
117  av_init_packet(&enc_pkt);
118  enc_pkt.data = NULL;
119  enc_pkt.size = 0;
120 
121  if ((ret = avcodec_send_frame(encoder_ctx, frame)) < 0) {
122  fprintf(stderr, "Error during encoding. Error code: %s\n", av_err2str(ret));
123  goto end;
124  }
125  while (1) {
127  if (ret)
128  break;
129 
130  enc_pkt.stream_index = 0;
132  ofmt_ctx->streams[0]->time_base);
134  if (ret < 0) {
135  fprintf(stderr, "Error during writing data to output file. "
136  "Error code: %s\n", av_err2str(ret));
137  return -1;
138  }
139  }
140 
141 end:
142  if (ret == AVERROR_EOF)
143  return 0;
144  ret = ((ret == AVERROR(EAGAIN)) ? 0:-1);
145  return ret;
146 }
147 
148 static int dec_enc(AVPacket *pkt, AVCodec *enc_codec)
149 {
150  AVFrame *frame;
151  int ret = 0;
152 
154  if (ret < 0) {
155  fprintf(stderr, "Error during decoding. Error code: %s\n", av_err2str(ret));
156  return ret;
157  }
158 
159  while (ret >= 0) {
160  if (!(frame = av_frame_alloc()))
161  return AVERROR(ENOMEM);
162 
164  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
166  return 0;
167  } else if (ret < 0) {
168  fprintf(stderr, "Error while decoding. Error code: %s\n", av_err2str(ret));
169  goto fail;
170  }
171 
172  if (!initialized) {
173  /* we need to ref hw_frames_ctx of decoder to initialize encoder's codec.
174  Only after we get a decoded frame, can we obtain its hw_frames_ctx */
176  if (!encoder_ctx->hw_frames_ctx) {
177  ret = AVERROR(ENOMEM);
178  goto fail;
179  }
180  /* set AVCodecContext Parameters for encoder, here we keep them stay
181  * the same as decoder.
182  * xxx: now the sample can't handle resolution change case.
183  */
188 
189  if ((ret = avcodec_open2(encoder_ctx, enc_codec, NULL)) < 0) {
190  fprintf(stderr, "Failed to open encode codec. Error code: %s\n",
191  av_err2str(ret));
192  goto fail;
193  }
194 
195  if (!(ost = avformat_new_stream(ofmt_ctx, enc_codec))) {
196  fprintf(stderr, "Failed to allocate stream for output format.\n");
197  ret = AVERROR(ENOMEM);
198  goto fail;
199  }
200 
203  if (ret < 0) {
204  fprintf(stderr, "Failed to copy the stream parameters. "
205  "Error code: %s\n", av_err2str(ret));
206  goto fail;
207  }
208 
209  /* write the stream header */
210  if ((ret = avformat_write_header(ofmt_ctx, NULL)) < 0) {
211  fprintf(stderr, "Error while writing stream header. "
212  "Error code: %s\n", av_err2str(ret));
213  goto fail;
214  }
215 
216  initialized = 1;
217  }
218 
219  if ((ret = encode_write(frame)) < 0)
220  fprintf(stderr, "Error during encoding and writing.\n");
221 
222 fail:
224  if (ret < 0)
225  return ret;
226  }
227  return 0;
228 }
229 
230 int main(int argc, char **argv)
231 {
232  int ret = 0;
233  AVPacket dec_pkt;
234  AVCodec *enc_codec;
235 
236  if (argc != 4) {
237  fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"
238  "The output format is guessed according to the file extension.\n"
239  "\n", argv[0]);
240  return -1;
241  }
242 
244  if (ret < 0) {
245  fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));
246  return -1;
247  }
248 
249  if ((ret = open_input_file(argv[1])) < 0)
250  goto end;
251 
252  if (!(enc_codec = avcodec_find_encoder_by_name(argv[2]))) {
253  fprintf(stderr, "Could not find encoder '%s'\n", argv[2]);
254  ret = -1;
255  goto end;
256  }
257 
258  if ((ret = (avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, argv[3]))) < 0) {
259  fprintf(stderr, "Failed to deduce output format from file extension. Error code: "
260  "%s\n", av_err2str(ret));
261  goto end;
262  }
263 
264  if (!(encoder_ctx = avcodec_alloc_context3(enc_codec))) {
265  ret = AVERROR(ENOMEM);
266  goto end;
267  }
268 
269  ret = avio_open(&ofmt_ctx->pb, argv[3], AVIO_FLAG_WRITE);
270  if (ret < 0) {
271  fprintf(stderr, "Cannot open output file. "
272  "Error code: %s\n", av_err2str(ret));
273  goto end;
274  }
275 
276  /* read all packets and only transcoding video */
277  while (ret >= 0) {
278  if ((ret = av_read_frame(ifmt_ctx, &dec_pkt)) < 0)
279  break;
280 
281  if (video_stream == dec_pkt.stream_index)
282  ret = dec_enc(&dec_pkt, enc_codec);
283 
284  av_packet_unref(&dec_pkt);
285  }
286 
287  /* flush decoder */
288  dec_pkt.data = NULL;
289  dec_pkt.size = 0;
290  ret = dec_enc(&dec_pkt, enc_codec);
291  av_packet_unref(&dec_pkt);
292 
293  /* flush encoder */
294  ret = encode_write(NULL);
295 
296  /* write the trailer for output stream */
298 
299 end:
305  return ret;
306 }
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:605
AVCodec
AVCodec.
Definition: codec.h:190
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:422
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4526
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:778
ofmt_ctx
static AVFormatContext * ofmt_ctx
Definition: vaapi_transcode.c:41
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
avcodec_parameters_from_context
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: utils.c:2127
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
end
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1403
AVPacket::data
uint8_t * data
Definition: packet.h:355
dec_enc
static int dec_enc(AVPacket *pkt, AVCodec *enc_codec)
Definition: vaapi_transcode.c:148
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1780
ost
static AVStream * ost
Definition: vaapi_transcode.c:45
ifmt_ctx
static AVFormatContext * ifmt_ctx
Definition: vaapi_transcode.c:41
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:2069
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4498
decoder
static const chunk_decoder decoder[8]
Definition: dfa.c:330
encode_write
static int encode_write(AVFrame *frame)
Definition: vaapi_transcode.c:112
get_vaapi_format
static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
Definition: vaapi_transcode.c:48
fail
#define fail()
Definition: checkasm.h:123
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
initialized
static int initialized
Definition: vaapi_transcode.c:46
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:157
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:649
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:675
decoder_ctx
static AVCodecContext * decoder_ctx
Definition: vaapi_transcode.c:43
ctx
AVFormatContext * ctx
Definition: movenc.c:48
open_input_file
static int open_input_file(const char *filename)
Definition: vaapi_transcode.c:62
avformat_write_header
av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and write the stream header to an output media file.
Definition: mux.c:505
AVFormatContext
Format I/O context.
Definition: avformat.h:1335
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1012
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:894
NULL
#define NULL
Definition: coverity.c:32
av_buffer_unref
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it.
Definition: buffer.c:125
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:172
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1377
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:565
AVCodecContext::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avcodec.h:649
main
int main(int argc, char **argv)
Definition: vaapi_transcode.c:230
avformat_find_stream_info
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3622
AVPacket::size
int size
Definition: packet.h:356
av_err2str
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
encoder_ctx
static AVCodecContext * encoder_ctx
Definition: vaapi_transcode.c:43
avformat_alloc_output_context2
int avformat_alloc_output_context2(AVFormatContext **ctx, ff_const59 AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:135
av_packet_rescale_ts
void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)
Convert valid timing fields (timestamps / durations) in a packet from one timebase to another.
Definition: avpacket.c:712
AV_PIX_FMT_VAAPI
@ AV_PIX_FMT_VAAPI
Definition: pixfmt.h:122
hw_device_ctx
static AVBufferRef * hw_device_ctx
Definition: vaapi_transcode.c:42
AV_HWDEVICE_TYPE_VAAPI
@ AV_HWDEVICE_TYPE_VAAPI
Definition: hwcontext.h:31
avcodec_find_encoder_by_name
AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
Definition: allcodecs.c:942
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:586
av_write_trailer
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1251
avformat_open_input
int avformat_open_input(AVFormatContext **ps, const char *url, ff_const59 AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:536
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: utils.c:2184
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
AVCodecContext::hw_device_ctx
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:2278
AVCodecContext::height
int height
Definition: avcodec.h:699
avcodec_send_frame
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:392
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:736
AVCodecContext::hw_frames_ctx
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames.
Definition: avcodec.h:2226
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:865
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
av_hwdevice_ctx_create
int av_hwdevice_ctx_create(AVBufferRef **pdevice_ref, enum AVHWDeviceType type, const char *device, AVDictionary *opts, int flags)
Open a device of the specified type and create an AVHWDeviceContext for it.
Definition: hwcontext.c:610
avformat.h
AVCodecContext
main external API structure.
Definition: avcodec.h:526
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
video
A Quick Description Of Rate Distortion Theory We want to encode a video
Definition: rate_distortion.txt:3
avio_open
int avio_open(AVIOContext **s, const char *url, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: aviobuf.c:1115
AVPacket::stream_index
int stream_index
Definition: packet.h:357
av_buffer_ref
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:81
video_stream
static int video_stream
Definition: vaapi_transcode.c:44
AVPacket
This structure stores compressed data.
Definition: packet.h:332
av_interleaved_write_frame
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1236
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:699
hwcontext.h
av_init_packet
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:35
av_find_best_stream
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
Definition: utils.c:4251