FFmpeg
vaapi_transcode.c
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1 /*
2  * Permission is hereby granted, free of charge, to any person obtaining a copy
3  * of this software and associated documentation files (the "Software"), to deal
4  * in the Software without restriction, including without limitation the rights
5  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
6  * copies of the Software, and to permit persons to whom the Software is
7  * furnished to do so, subject to the following conditions:
8  *
9  * The above copyright notice and this permission notice shall be included in
10  * all copies or substantial portions of the Software.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
15  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
16  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
17  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
18  * THE SOFTWARE.
19  */
20 
21 /**
22  * @file Intel VAAPI-accelerated transcoding API usage example
23  * @example vaapi_transcode.c
24  *
25  * Perform VAAPI-accelerated transcoding.
26  * Usage: vaapi_transcode input_stream codec output_stream
27  * e.g: - vaapi_transcode input.mp4 h264_vaapi output_h264.mp4
28  * - vaapi_transcode input.mp4 vp9_vaapi output_vp9.ivf
29  */
30 
31 #include <stdio.h>
32 #include <errno.h>
33 
34 #include <libavutil/hwcontext.h>
35 #include <libavcodec/avcodec.h>
36 #include <libavformat/avformat.h>
37 
41 static int video_stream = -1;
42 static AVStream *ost;
43 static int initialized = 0;
44 
46  const enum AVPixelFormat *pix_fmts)
47 {
48  const enum AVPixelFormat *p;
49 
50  for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
51  if (*p == AV_PIX_FMT_VAAPI)
52  return *p;
53  }
54 
55  fprintf(stderr, "Unable to decode this file using VA-API.\n");
56  return AV_PIX_FMT_NONE;
57 }
58 
59 static int open_input_file(const char *filename)
60 {
61  int ret;
62  const AVCodec *decoder = NULL;
63  AVStream *video = NULL;
64 
65  if ((ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL)) < 0) {
66  fprintf(stderr, "Cannot open input file '%s', Error code: %s\n",
67  filename, av_err2str(ret));
68  return ret;
69  }
70 
72  fprintf(stderr, "Cannot find input stream information. Error code: %s\n",
73  av_err2str(ret));
74  return ret;
75  }
76 
78  if (ret < 0) {
79  fprintf(stderr, "Cannot find a video stream in the input file. "
80  "Error code: %s\n", av_err2str(ret));
81  return ret;
82  }
83  video_stream = ret;
84 
86  return AVERROR(ENOMEM);
87 
89  if ((ret = avcodec_parameters_to_context(decoder_ctx, video->codecpar)) < 0) {
90  fprintf(stderr, "avcodec_parameters_to_context error. Error code: %s\n",
91  av_err2str(ret));
92  return ret;
93  }
94 
96  if (!decoder_ctx->hw_device_ctx) {
97  fprintf(stderr, "A hardware device reference create failed.\n");
98  return AVERROR(ENOMEM);
99  }
101 
102  if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0)
103  fprintf(stderr, "Failed to open codec for decoding. Error code: %s\n",
104  av_err2str(ret));
105 
106  return ret;
107 }
108 
109 static int encode_write(AVPacket *enc_pkt, AVFrame *frame)
110 {
111  int ret = 0;
112 
113  av_packet_unref(enc_pkt);
114 
115  if ((ret = avcodec_send_frame(encoder_ctx, frame)) < 0) {
116  fprintf(stderr, "Error during encoding. Error code: %s\n", av_err2str(ret));
117  goto end;
118  }
119  while (1) {
121  if (ret)
122  break;
123 
124  enc_pkt->stream_index = 0;
126  ofmt_ctx->streams[0]->time_base);
128  if (ret < 0) {
129  fprintf(stderr, "Error during writing data to output file. "
130  "Error code: %s\n", av_err2str(ret));
131  return -1;
132  }
133  }
134 
135 end:
136  if (ret == AVERROR_EOF)
137  return 0;
138  ret = ((ret == AVERROR(EAGAIN)) ? 0:-1);
139  return ret;
140 }
141 
142 static int dec_enc(AVPacket *pkt, const AVCodec *enc_codec)
143 {
144  AVFrame *frame;
145  int ret = 0;
146 
148  if (ret < 0) {
149  fprintf(stderr, "Error during decoding. Error code: %s\n", av_err2str(ret));
150  return ret;
151  }
152 
153  while (ret >= 0) {
154  if (!(frame = av_frame_alloc()))
155  return AVERROR(ENOMEM);
156 
158  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
160  return 0;
161  } else if (ret < 0) {
162  fprintf(stderr, "Error while decoding. Error code: %s\n", av_err2str(ret));
163  goto fail;
164  }
165 
166  if (!initialized) {
167  /* we need to ref hw_frames_ctx of decoder to initialize encoder's codec.
168  Only after we get a decoded frame, can we obtain its hw_frames_ctx */
170  if (!encoder_ctx->hw_frames_ctx) {
171  ret = AVERROR(ENOMEM);
172  goto fail;
173  }
174  /* set AVCodecContext Parameters for encoder, here we keep them stay
175  * the same as decoder.
176  * xxx: now the sample can't handle resolution change case.
177  */
182 
183  if ((ret = avcodec_open2(encoder_ctx, enc_codec, NULL)) < 0) {
184  fprintf(stderr, "Failed to open encode codec. Error code: %s\n",
185  av_err2str(ret));
186  goto fail;
187  }
188 
189  if (!(ost = avformat_new_stream(ofmt_ctx, enc_codec))) {
190  fprintf(stderr, "Failed to allocate stream for output format.\n");
191  ret = AVERROR(ENOMEM);
192  goto fail;
193  }
194 
197  if (ret < 0) {
198  fprintf(stderr, "Failed to copy the stream parameters. "
199  "Error code: %s\n", av_err2str(ret));
200  goto fail;
201  }
202 
203  /* write the stream header */
204  if ((ret = avformat_write_header(ofmt_ctx, NULL)) < 0) {
205  fprintf(stderr, "Error while writing stream header. "
206  "Error code: %s\n", av_err2str(ret));
207  goto fail;
208  }
209 
210  initialized = 1;
211  }
212 
213  if ((ret = encode_write(pkt, frame)) < 0)
214  fprintf(stderr, "Error during encoding and writing.\n");
215 
216 fail:
218  if (ret < 0)
219  return ret;
220  }
221  return 0;
222 }
223 
224 int main(int argc, char **argv)
225 {
226  const AVCodec *enc_codec;
227  int ret = 0;
228  AVPacket *dec_pkt;
229 
230  if (argc != 4) {
231  fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"
232  "The output format is guessed according to the file extension.\n"
233  "\n", argv[0]);
234  return -1;
235  }
236 
238  if (ret < 0) {
239  fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));
240  return -1;
241  }
242 
243  dec_pkt = av_packet_alloc();
244  if (!dec_pkt) {
245  fprintf(stderr, "Failed to allocate decode packet\n");
246  goto end;
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  av_packet_unref(dec_pkt);
289  ret = dec_enc(dec_pkt, enc_codec);
290 
291  /* flush encoder */
292  ret = encode_write(dec_pkt, NULL);
293 
294  /* write the trailer for output stream */
296 
297 end:
303  av_packet_free(&dec_pkt);
304  return ret;
305 }
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:427
AVCodec
AVCodec.
Definition: codec.h:187
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:556
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
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:716
av_find_best_stream
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, const AVCodec **decoder_ret, int flags)
Definition: avformat.c:420
ofmt_ctx
static AVFormatContext * ofmt_ctx
Definition: vaapi_transcode.c:38
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:100
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1270
encode_write
static int encode_write(AVPacket *enc_pkt, AVFrame *frame)
Definition: vaapi_transcode.c:109
av_buffer_ref
AVBufferRef * av_buffer_ref(const AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:103
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: demux.c:1558
ost
static AVStream * ost
Definition: vaapi_transcode.c:42
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:74
ifmt_ctx
static AVFormatContext * ifmt_ctx
Definition: vaapi_transcode.c:38
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1807
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: demux.c:374
decoder
static const chunk_decoder decoder[8]
Definition: dfa.c:331
get_vaapi_format
static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
Definition: vaapi_transcode.c:45
fail
#define fail()
Definition: checkasm.h:179
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:88
pkt
AVPacket * pkt
Definition: movenc.c:59
avformat_open_input
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: demux.c:226
initialized
static int initialized
Definition: vaapi_transcode.c:43
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:154
avcodec_receive_frame
int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder or encoder (when the AV_CODEC_FLAG_RECON_FRAME flag is used...
Definition: avcodec.c:715
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:304
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:637
decoder_ctx
static AVCodecContext * decoder_ctx
Definition: vaapi_transcode.c:40
ctx
AVFormatContext * ctx
Definition: movenc.c:48
open_input_file
static int open_input_file(const char *filename)
Definition: vaapi_transcode.c:59
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:472
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVFormatContext
Format I/O context.
Definition: avformat.h:1202
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const struct AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
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:880
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:139
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:169
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1244
avcodec_open2
int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:128
dec_enc
static int dec_enc(AVPacket *pkt, const AVCodec *enc_codec)
Definition: vaapi_transcode.c:142
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:567
main
int main(int argc, char **argv)
Definition: vaapi_transcode.c:224
avformat_find_stream_info
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: demux.c:2532
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:121
encoder_ctx
static AVCodecContext * encoder_ctx
Definition: vaapi_transcode.c:40
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:63
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:531
AV_PIX_FMT_VAAPI
@ AV_PIX_FMT_VAAPI
Hardware acceleration through VA-API, data[3] contains a VASurfaceID.
Definition: pixfmt.h:126
hw_device_ctx
static AVBufferRef * hw_device_ctx
Definition: vaapi_transcode.c:39
AV_HWDEVICE_TYPE_VAAPI
@ AV_HWDEVICE_TYPE_VAAPI
Definition: hwcontext.h:31
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:709
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:1286
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:1985
AVCodecContext::height
int height
Definition: avcodec.h:625
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:518
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:662
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:1944
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:841
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:618
avformat.h
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
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:1303
AVPacket::stream_index
int stream_index
Definition: packet.h:524
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
avcodec_parameters_from_context
int avcodec_parameters_from_context(struct AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:137
video_stream
static int video_stream
Definition: vaapi_transcode.c:41
AVPacket
This structure stores compressed data.
Definition: packet.h:499
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:1271
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:625
hwcontext.h
avformat_alloc_output_context2
int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:93
avcodec_find_encoder_by_name
const AVCodec * avcodec_find_encoder_by_name(const char *name)
Find a registered encoder with the specified name.
Definition: allcodecs.c:1004