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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:1154
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:3073
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:226
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1185
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:1453
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:655
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1750
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3441
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:1663
Format I/O context.
Definition: avformat.h:1351
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:4455
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
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:2092
static AVFrame * frame
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:1452
#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:905
int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:148
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:4183
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:700
#define AVERROR(e)
Definition: error.h:43
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
#define fail()
Definition: checkasm.h:117
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:1713
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:3230
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
static int video_stream
Stream structure.
Definition: avformat.h:874
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:1393
main external API structure.
Definition: avcodec.h:1540
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:598
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:387
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:1792
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:2035
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:266
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:3564
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:4427
int main(int argc, char **argv)
static AVFormatContext * ifmt_ctx
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:537
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1247
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
int stream_index
Definition: avcodec.h:1454
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:903
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:3282
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1429