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 
74  if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) < 0) {
75  fprintf(stderr, "Cannot find input stream information. Error code: %s\n",
76  av_err2str(ret));
77  return ret;
78  }
79 
80  ret = av_find_best_stream(ifmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
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 
88  if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
89  return AVERROR(ENOMEM);
90 
91  video = ifmt_ctx->streams[video_stream];
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 
98  decoder_ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
99  if (!decoder_ctx->hw_device_ctx) {
100  fprintf(stderr, "A hardware device reference create failed.\n");
101  return AVERROR(ENOMEM);
102  }
103  decoder_ctx->get_format = get_vaapi_format;
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) {
126  ret = avcodec_receive_packet(encoder_ctx, &enc_pkt);
127  if (ret)
128  break;
129 
130  enc_pkt.stream_index = 0;
131  av_packet_rescale_ts(&enc_pkt, ifmt_ctx->streams[video_stream]->time_base,
132  ofmt_ctx->streams[0]->time_base);
133  ret = av_interleaved_write_frame(ofmt_ctx, &enc_pkt);
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 
153  ret = avcodec_send_packet(decoder_ctx, pkt);
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 
163  ret = avcodec_receive_frame(decoder_ctx, frame);
164  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
165  av_frame_free(&frame);
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  */
184  encoder_ctx->time_base = av_inv_q(decoder_ctx->framerate);
186  encoder_ctx->width = decoder_ctx->width;
187  encoder_ctx->height = decoder_ctx->height;
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:
223  av_frame_free(&frame);
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 
243  ret = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI, NULL, NULL, 0);
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:
300  avformat_close_input(&ifmt_ctx);
302  avcodec_free_context(&decoder_ctx);
304  av_buffer_unref(&hw_device_ctx);
305  return ret;
306 }
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:1153
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:1817
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:3105
static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
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
static int encode_write(AVFrame *frame)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1192
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:417
static AVCodecContext * decoder_ctx
int size
Definition: avcodec.h:1478
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:655
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
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:537
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3481
static int open_input_file(const char *filename)
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1688
Format I/O context.
Definition: avformat.h:1358
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4459
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
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:2095
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:571
uint8_t * data
Definition: avcodec.h:1477
#define AVERROR_EOF
End of file.
Definition: error.h:55
static AVBufferRef * hw_device_ctx
AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
Definition: allcodecs.c:913
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:4186
void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst)
Convert valid timing fields (timestamps / durations) in a packet from one timebase to another...
Definition: avpacket.c:704
static AVFormatContext * ofmt_ctx
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:740
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:148
#define fail()
Definition: checkasm.h:120
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:508
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:156
static const chunk_decoder decoder[8]
Definition: dfa.c:330
int width
picture width / height.
Definition: avcodec.h:1738
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:3262
static int initialized
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
AVFormatContext * ctx
Definition: movenc.c:48
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
static int video_stream
Stream structure.
Definition: avformat.h:881
static AVCodecContext * encoder_ctx
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:677
Libavcodec external API header.
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:171
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
main external API structure.
Definition: avcodec.h:1565
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:387
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:2038
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:542
static int dec_enc(AVPacket *pkt, AVCodec *enc_codec)
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1768
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
A reference to a data buffer.
Definition: buffer.h:81
static AVStream * ost
Main libavformat public API header.
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3567
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:33
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4431
int main(int argc, char **argv)
static AVFormatContext * ifmt_ctx
A Quick Description Of Rate Distortion Theory We want to encode a video
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1254
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1479
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:910
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
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:3314
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1454