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 
112 static int encode_write(AVPacket *enc_pkt, AVFrame *frame)
113 {
114  int ret = 0;
115 
116  av_packet_unref(enc_pkt);
117 
118  if ((ret = avcodec_send_frame(encoder_ctx, frame)) < 0) {
119  fprintf(stderr, "Error during encoding. Error code: %s\n", av_err2str(ret));
120  goto end;
121  }
122  while (1) {
123  ret = avcodec_receive_packet(encoder_ctx, enc_pkt);
124  if (ret)
125  break;
126 
127  enc_pkt->stream_index = 0;
128  av_packet_rescale_ts(enc_pkt, ifmt_ctx->streams[video_stream]->time_base,
129  ofmt_ctx->streams[0]->time_base);
130  ret = av_interleaved_write_frame(ofmt_ctx, enc_pkt);
131  if (ret < 0) {
132  fprintf(stderr, "Error during writing data to output file. "
133  "Error code: %s\n", av_err2str(ret));
134  return -1;
135  }
136  }
137 
138 end:
139  if (ret == AVERROR_EOF)
140  return 0;
141  ret = ((ret == AVERROR(EAGAIN)) ? 0:-1);
142  return ret;
143 }
144 
145 static int dec_enc(AVPacket *pkt, AVCodec *enc_codec)
146 {
147  AVFrame *frame;
148  int ret = 0;
149 
150  ret = avcodec_send_packet(decoder_ctx, pkt);
151  if (ret < 0) {
152  fprintf(stderr, "Error during decoding. Error code: %s\n", av_err2str(ret));
153  return ret;
154  }
155 
156  while (ret >= 0) {
157  if (!(frame = av_frame_alloc()))
158  return AVERROR(ENOMEM);
159 
160  ret = avcodec_receive_frame(decoder_ctx, frame);
161  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
162  av_frame_free(&frame);
163  return 0;
164  } else if (ret < 0) {
165  fprintf(stderr, "Error while decoding. Error code: %s\n", av_err2str(ret));
166  goto fail;
167  }
168 
169  if (!initialized) {
170  /* we need to ref hw_frames_ctx of decoder to initialize encoder's codec.
171  Only after we get a decoded frame, can we obtain its hw_frames_ctx */
173  if (!encoder_ctx->hw_frames_ctx) {
174  ret = AVERROR(ENOMEM);
175  goto fail;
176  }
177  /* set AVCodecContext Parameters for encoder, here we keep them stay
178  * the same as decoder.
179  * xxx: now the sample can't handle resolution change case.
180  */
181  encoder_ctx->time_base = av_inv_q(decoder_ctx->framerate);
183  encoder_ctx->width = decoder_ctx->width;
184  encoder_ctx->height = decoder_ctx->height;
185 
186  if ((ret = avcodec_open2(encoder_ctx, enc_codec, NULL)) < 0) {
187  fprintf(stderr, "Failed to open encode codec. Error code: %s\n",
188  av_err2str(ret));
189  goto fail;
190  }
191 
192  if (!(ost = avformat_new_stream(ofmt_ctx, enc_codec))) {
193  fprintf(stderr, "Failed to allocate stream for output format.\n");
194  ret = AVERROR(ENOMEM);
195  goto fail;
196  }
197 
200  if (ret < 0) {
201  fprintf(stderr, "Failed to copy the stream parameters. "
202  "Error code: %s\n", av_err2str(ret));
203  goto fail;
204  }
205 
206  /* write the stream header */
207  if ((ret = avformat_write_header(ofmt_ctx, NULL)) < 0) {
208  fprintf(stderr, "Error while writing stream header. "
209  "Error code: %s\n", av_err2str(ret));
210  goto fail;
211  }
212 
213  initialized = 1;
214  }
215 
216  if ((ret = encode_write(pkt, frame)) < 0)
217  fprintf(stderr, "Error during encoding and writing.\n");
218 
219 fail:
220  av_frame_free(&frame);
221  if (ret < 0)
222  return ret;
223  }
224  return 0;
225 }
226 
227 int main(int argc, char **argv)
228 {
229  int ret = 0;
230  AVPacket *dec_pkt;
231  AVCodec *enc_codec;
232 
233  if (argc != 4) {
234  fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"
235  "The output format is guessed according to the file extension.\n"
236  "\n", argv[0]);
237  return -1;
238  }
239 
240  ret = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI, NULL, NULL, 0);
241  if (ret < 0) {
242  fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));
243  return -1;
244  }
245 
246  dec_pkt = av_packet_alloc();
247  if (!dec_pkt) {
248  fprintf(stderr, "Failed to allocate decode packet\n");
249  goto end;
250  }
251 
252  if ((ret = open_input_file(argv[1])) < 0)
253  goto end;
254 
255  if (!(enc_codec = avcodec_find_encoder_by_name(argv[2]))) {
256  fprintf(stderr, "Could not find encoder '%s'\n", argv[2]);
257  ret = -1;
258  goto end;
259  }
260 
261  if ((ret = (avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, argv[3]))) < 0) {
262  fprintf(stderr, "Failed to deduce output format from file extension. Error code: "
263  "%s\n", av_err2str(ret));
264  goto end;
265  }
266 
267  if (!(encoder_ctx = avcodec_alloc_context3(enc_codec))) {
268  ret = AVERROR(ENOMEM);
269  goto end;
270  }
271 
272  ret = avio_open(&ofmt_ctx->pb, argv[3], AVIO_FLAG_WRITE);
273  if (ret < 0) {
274  fprintf(stderr, "Cannot open output file. "
275  "Error code: %s\n", av_err2str(ret));
276  goto end;
277  }
278 
279  /* read all packets and only transcoding video */
280  while (ret >= 0) {
281  if ((ret = av_read_frame(ifmt_ctx, dec_pkt)) < 0)
282  break;
283 
284  if (video_stream == dec_pkt->stream_index)
285  ret = dec_enc(dec_pkt, enc_codec);
286 
287  av_packet_unref(dec_pkt);
288  }
289 
290  /* flush decoder */
291  av_packet_unref(dec_pkt);
292  ret = dec_enc(dec_pkt, enc_codec);
293 
294  /* flush encoder */
295  ret = encode_write(dec_pkt, NULL);
296 
297  /* write the trailer for output stream */
299 
300 end:
301  avformat_close_input(&ifmt_ctx);
303  avcodec_free_context(&decoder_ctx);
305  av_buffer_unref(&hw_device_ctx);
306  av_packet_free(&dec_pkt);
307  return ret;
308 }
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:1137
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:788
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:2071
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
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1259
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:395
static AVCodecContext * decoder_ctx
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:675
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
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:547
AVPacket * pkt
Definition: movenc.c:59
AVCodec.
Definition: codec.h:197
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:659
Format I/O context.
Definition: avformat.h:1247
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:75
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:191
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4553
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1315
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:147
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
#define AVERROR_EOF
End of file.
Definition: error.h:55
static AVBufferRef * hw_device_ctx
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:4275
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:737
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:204
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:643
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:136
#define fail()
Definition: checkasm.h:133
AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
Definition: allcodecs.c:969
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:506
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:170
static const chunk_decoder decoder[8]
Definition: dfa.c:330
int width
picture width / height.
Definition: avcodec.h:709
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames...
Definition: avcodec.h:2218
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:884
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:580
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:185
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
main external API structure.
Definition: avcodec.h:536
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:634
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:364
static int encode_write(AVPacket *enc_pkt, AVFrame *frame)
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:90
int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:142
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:1772
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:303
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:84
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:3650
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:93
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4525
int main(int argc, char **argv)
static AVFormatContext * ifmt_ctx
A Quick Description Of Rate Distortion Theory We want to encode a video
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:64
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1274
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
int stream_index
Definition: packet.h:371
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:913
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:2270
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: packet.h:346