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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 */

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 */

31 #include <stdio.h>

32 #include <errno.h>

34 #include <libavutil/hwcontext.h>

35 #include <libavcodec/avcodec.h>

36 #include <libavformat/avformat.h>

38 static AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;

39 static AVBufferRef *hw_device_ctx = NULL;

40 static AVCodecContext *decoder_ctx = NULL, *encoder_ctx = NULL;

41 static int video_stream = -1;

42 static AVStream *ost;

43 static int initialized = 0;

45 static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx,

46 const enum AVPixelFormat *pix_fmts)

47 {

48 const enum AVPixelFormat *p;

50 for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {

51 if (*p == AV_PIX_FMT_VAAPI)

52 return *p;

53 }

55 fprintf(stderr, "Unable to decode this file using VA-API.\n");

56 return AV_PIX_FMT_NONE;

57 }

59 static int open_input_file(const char *filename)

60 {

61 int ret;

62 const AVCodec *decoder = NULL;

63 AVStream *video = NULL;

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 }

71 if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) < 0) {

72 fprintf(stderr, "Cannot find input stream information. Error code: %s\n",

73 av_err2str(ret));

74 return ret;

75 }

77 ret = av_find_best_stream(ifmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);

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;

85 if (!(decoder_ctx = avcodec_alloc_context3(decoder)))

86 return AVERROR(ENOMEM);

88 video = ifmt_ctx->streams[video_stream];

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 }

95 decoder_ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);

96 if (!decoder_ctx->hw_device_ctx) {

97 fprintf(stderr, "A hardware device reference create failed.\n");

98 return AVERROR(ENOMEM);

99 }

100 decoder_ctx->get_format = get_vaapi_format;

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) {

120 ret = avcodec_receive_packet(encoder_ctx, enc_pkt);

121 if (ret)

122 break;

123

124 enc_pkt->stream_index = 0;

125 av_packet_rescale_ts(enc_pkt, ifmt_ctx->streams[video_stream]->time_base,

126 ofmt_ctx->streams[0]->time_base);

127 ret = av_interleaved_write_frame(ofmt_ctx, enc_pkt);

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

147 ret = avcodec_send_packet(decoder_ctx, pkt);

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

157 ret = avcodec_receive_frame(decoder_ctx, frame);

158 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {

159 av_frame_free(&frame);

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 */

169 encoder_ctx->hw_frames_ctx = av_buffer_ref(decoder_ctx->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 */

178 encoder_ctx->time_base = av_inv_q(decoder_ctx->framerate);

179 encoder_ctx->pix_fmt = AV_PIX_FMT_VAAPI;

180 encoder_ctx->width = decoder_ctx->width;

181 encoder_ctx->height = decoder_ctx->height;

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

195 ost->time_base = encoder_ctx->time_base;

196 ret = avcodec_parameters_from_context(ost->codecpar, encoder_ctx);

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:

217 av_frame_free(&frame);

218 }

219 return ret;

220 }

221

222 int main(int argc, char **argv)

223 {

224 const AVCodec *enc_codec;

225 int ret = 0;

226 AVPacket *dec_pkt;

227

228 if (argc != 4) {

229 fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"

230 "The output format is guessed according to the file extension.\n"

231 "\n", argv[0]);

232 return -1;

233 }

234

235 ret = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI, NULL, NULL, 0);

236 if (ret < 0) {

237 fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));

238 return -1;

239 }

240

241 dec_pkt = av_packet_alloc();

242 if (!dec_pkt) {

243 fprintf(stderr, "Failed to allocate decode packet\n");

244 goto end;

245 }

246

247 if ((ret = open_input_file(argv[1])) < 0)

248 goto end;

249

250 if (!(enc_codec = avcodec_find_encoder_by_name(argv[2]))) {

251 fprintf(stderr, "Could not find encoder '%s'\n", argv[2]);

252 ret = -1;

253 goto end;

254 }

255

256 if ((ret = (avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, argv[3]))) < 0) {

257 fprintf(stderr, "Failed to deduce output format from file extension. Error code: "

258 "%s\n", av_err2str(ret));

259 goto end;

260 }

261

262 if (!(encoder_ctx = avcodec_alloc_context3(enc_codec))) {

263 ret = AVERROR(ENOMEM);

264 goto end;

265 }

266

267 ret = avio_open(&ofmt_ctx->pb, argv[3], AVIO_FLAG_WRITE);

268 if (ret < 0) {

269 fprintf(stderr, "Cannot open output file. "

270 "Error code: %s\n", av_err2str(ret));

271 goto end;

272 }

273

274 /* read all packets and only transcoding video */

275 while (ret >= 0) {

276 if ((ret = av_read_frame(ifmt_ctx, dec_pkt)) < 0)

277 break;

278

279 if (video_stream == dec_pkt->stream_index)

280 ret = dec_enc(dec_pkt, enc_codec);

281

282 av_packet_unref(dec_pkt);

283 }

284

285 /* flush decoder */

286 av_packet_unref(dec_pkt);

287 ret = dec_enc(dec_pkt, enc_codec);

288

289 /* flush encoder */

290 ret = encode_write(dec_pkt, NULL);

291

292 /* write the trailer for output stream */

293 av_write_trailer(ofmt_ctx);

294

295 end:

296 avformat_close_input(&ifmt_ctx);

297 avformat_close_input(&ofmt_ctx);

298 avcodec_free_context(&decoder_ctx);

299 avcodec_free_context(&encoder_ctx);

300 av_buffer_unref(&hw_device_ctx);

301 av_packet_free(&dec_pkt);

302 return ret;

303 }

av_packet_unref

void av_packet_unref(AVPacket *pkt)

Wipe the packet.

Definition: packet.c:429

AVCodec

AVCodec.

Definition: codec.h:187

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:541

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:793

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:448

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:162

AVFrame

This structure describes decoded (raw) audio or video data.

Definition: frame.h:389

AVFormatContext::streams

AVStream ** streams

A list of all streams in the file.

Definition: avformat.h:1355

avio_open

int avio_open(AVIOContext **s, const char *filename, int flags)

Create and initialize a AVIOContext for accessing the resource indicated by url.

Definition: avio.c:497

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:1538

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: packet.c:74

ifmt_ctx

static AVFormatContext * ifmt_ctx

Definition: vaapi_transcode.c:38

AVCodecContext::framerate

AVRational framerate

Definition: avcodec.h:566

avformat_close_input

void avformat_close_input(AVFormatContext **s)

Close an opened input AVFormatContext.

Definition: demux.c:363

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:188

av_frame_alloc

AVFrame * av_frame_alloc(void)

Allocate an AVFrame and set its fields to default values.

Definition: frame.c:150

pkt

AVPacket * pkt

Definition: movenc.c:60

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:215

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:149

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:713

pix_fmts

static enum AVPixelFormat pix_fmts[]

Definition: libkvazaar.c:304

AVIO_FLAG_WRITE

#define AVIO_FLAG_WRITE

write-only

Definition: avio.h:618

decoder_ctx

static AVCodecContext * decoder_ctx

Definition: vaapi_transcode.c:40

ctx

AVFormatContext * ctx

Definition: movenc.c:49

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:487

AVFormatContext

Format I/O context.

Definition: avformat.h:1287

AVStream::codecpar

AVCodecParameters * codecpar

Codec parameters associated with this stream.

Definition: avformat.h:771

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:787

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:164

AVFormatContext::pb

AVIOContext * pb

I/O context.

Definition: avformat.h:1329

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:143

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:550

main

int main(int argc, char **argv)

Definition: vaapi_transcode.c:222

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:2516

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:122

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: packet.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: packet.c:533

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:727

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:1295

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:1507

AVCodecContext::height

int height

Definition: avcodec.h:624

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:508

AVCodecContext::pix_fmt

enum AVPixelFormat pix_fmt

Pixel format, see AV_PIX_FMT_xxx.

Definition: avcodec.h:663

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:1485

avcodec.h

ret

Definition: filter_design.txt:187

AVStream

Stream structure.

Definition: avformat.h:748

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:600

avformat.h

AVCodecContext

main external API structure.

Definition: avcodec.h:451

AV_PIX_FMT_NONE

@ AV_PIX_FMT_NONE

Definition: pixfmt.h:72