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hw_decode.c
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1 /*
2  * Copyright (c) 2017 Jun Zhao
3  * Copyright (c) 2017 Kaixuan Liu
4  *
5  * HW Acceleration API (video decoding) decode sample
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * HW-Accelerated decoding example.
27  *
28  * @example hw_decode.c
29  * This example shows how to do HW-accelerated decoding with output
30  * frames from the HW video surfaces.
31  */
32 
33 #include <stdio.h>
34 
35 #include <libavcodec/avcodec.h>
36 #include <libavformat/avformat.h>
37 #include <libavutil/pixdesc.h>
38 #include <libavutil/hwcontext.h>
39 #include <libavutil/opt.h>
40 #include <libavutil/avassert.h>
41 #include <libavutil/imgutils.h>
42 
45 static FILE *output_file = NULL;
46 
48 {
49  enum AVPixelFormat fmt;
50 
51  switch (type) {
53  fmt = AV_PIX_FMT_VAAPI;
54  break;
57  break;
59  fmt = AV_PIX_FMT_D3D11;
60  break;
62  fmt = AV_PIX_FMT_VDPAU;
63  break;
66  break;
67  default:
68  fmt = AV_PIX_FMT_NONE;
69  break;
70  }
71 
72  return fmt;
73 }
74 
76 {
77  int err = 0;
78 
79  if ((err = av_hwdevice_ctx_create(&hw_device_ctx, type,
80  NULL, NULL, 0)) < 0) {
81  fprintf(stderr, "Failed to create specified HW device.\n");
82  return err;
83  }
84  ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
85 
86  return err;
87 }
88 
90  const enum AVPixelFormat *pix_fmts)
91 {
92  const enum AVPixelFormat *p;
93 
94  for (p = pix_fmts; *p != -1; p++) {
95  if (*p == hw_pix_fmt)
96  return *p;
97  }
98 
99  fprintf(stderr, "Failed to get HW surface format.\n");
100  return AV_PIX_FMT_NONE;
101 }
102 
103 static int decode_write(AVCodecContext *avctx, AVPacket *packet)
104 {
105  AVFrame *frame = NULL, *sw_frame = NULL;
106  AVFrame *tmp_frame = NULL;
107  uint8_t *buffer = NULL;
108  int size;
109  int ret = 0;
110 
111  ret = avcodec_send_packet(avctx, packet);
112  if (ret < 0) {
113  fprintf(stderr, "Error during decoding\n");
114  return ret;
115  }
116 
117  while (ret >= 0) {
118  if (!(frame = av_frame_alloc()) || !(sw_frame = av_frame_alloc())) {
119  fprintf(stderr, "Can not alloc frame\n");
120  ret = AVERROR(ENOMEM);
121  goto fail;
122  }
123 
124  ret = avcodec_receive_frame(avctx, frame);
125  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
126  av_frame_free(&frame);
127  av_frame_free(&sw_frame);
128  return 0;
129  } else if (ret < 0) {
130  fprintf(stderr, "Error while decoding\n");
131  goto fail;
132  }
133 
134  if (frame->format == hw_pix_fmt) {
135  /* retrieve data from GPU to CPU */
136  if ((ret = av_hwframe_transfer_data(sw_frame, frame, 0)) < 0) {
137  fprintf(stderr, "Error transferring the data to system memory\n");
138  goto fail;
139  }
140  tmp_frame = sw_frame;
141  } else
142  tmp_frame = frame;
143 
144  size = av_image_get_buffer_size(tmp_frame->format, tmp_frame->width,
145  tmp_frame->height, 1);
146  buffer = av_malloc(size);
147  if (!buffer) {
148  fprintf(stderr, "Can not alloc buffer\n");
149  ret = AVERROR(ENOMEM);
150  goto fail;
151  }
152  ret = av_image_copy_to_buffer(buffer, size,
153  (const uint8_t * const *)tmp_frame->data,
154  (const int *)tmp_frame->linesize, tmp_frame->format,
155  tmp_frame->width, tmp_frame->height, 1);
156  if (ret < 0) {
157  fprintf(stderr, "Can not copy image to buffer\n");
158  goto fail;
159  }
160 
161  if ((ret = fwrite(buffer, 1, size, output_file)) < 0) {
162  fprintf(stderr, "Failed to dump raw data.\n");
163  goto fail;
164  }
165 
166  fail:
167  av_frame_free(&frame);
168  av_frame_free(&sw_frame);
169  if (buffer)
170  av_freep(&buffer);
171  if (ret < 0)
172  return ret;
173  }
174 
175  return 0;
176 }
177 
178 int main(int argc, char *argv[])
179 {
180  AVFormatContext *input_ctx = NULL;
181  int video_stream, ret;
182  AVStream *video = NULL;
183  AVCodecContext *decoder_ctx = NULL;
184  AVCodec *decoder = NULL;
185  AVPacket packet;
186  enum AVHWDeviceType type;
187 
188  if (argc < 4) {
189  fprintf(stderr, "Usage: %s <vaapi|vdpau|dxva2|d3d11va> <input file> <output file>\n", argv[0]);
190  return -1;
191  }
192 
193  av_register_all();
194 
195  type = av_hwdevice_find_type_by_name(argv[1]);
197  if (hw_pix_fmt == -1) {
198  fprintf(stderr, "Cannot support '%s' in this example.\n", argv[1]);
199  return -1;
200  }
201 
202  /* open the input file */
203  if (avformat_open_input(&input_ctx, argv[2], NULL, NULL) != 0) {
204  fprintf(stderr, "Cannot open input file '%s'\n", argv[2]);
205  return -1;
206  }
207 
208  if (avformat_find_stream_info(input_ctx, NULL) < 0) {
209  fprintf(stderr, "Cannot find input stream information.\n");
210  return -1;
211  }
212 
213  /* find the video stream information */
214  ret = av_find_best_stream(input_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
215  if (ret < 0) {
216  fprintf(stderr, "Cannot find a video stream in the input file\n");
217  return -1;
218  }
219  video_stream = ret;
220 
221  if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
222  return AVERROR(ENOMEM);
223 
224  video = input_ctx->streams[video_stream];
225  if (avcodec_parameters_to_context(decoder_ctx, video->codecpar) < 0)
226  return -1;
227 
228  decoder_ctx->get_format = get_hw_format;
229  av_opt_set_int(decoder_ctx, "refcounted_frames", 1, 0);
230 
231  if (hw_decoder_init(decoder_ctx, type) < 0)
232  return -1;
233 
234  if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0) {
235  fprintf(stderr, "Failed to open codec for stream #%u\n", video_stream);
236  return -1;
237  }
238 
239  /* open the file to dump raw data */
240  output_file = fopen(argv[3], "w+");
241 
242  /* actual decoding and dump the raw data */
243  while (ret >= 0) {
244  if ((ret = av_read_frame(input_ctx, &packet)) < 0)
245  break;
246 
247  if (video_stream == packet.stream_index)
248  ret = decode_write(decoder_ctx, &packet);
249 
250  av_packet_unref(&packet);
251  }
252 
253  /* flush the decoder */
254  packet.data = NULL;
255  packet.size = 0;
256  ret = decode_write(decoder_ctx, &packet);
257  av_packet_unref(&packet);
258 
259  if (output_file)
260  fclose(output_file);
261  avcodec_free_context(&decoder_ctx);
262  avformat_close_input(&input_ctx);
263  av_buffer_unref(&hw_device_ctx);
264 
265  return 0;
266 }
#define NULL
Definition: coverity.c:32
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:201
int av_image_copy_to_buffer(uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
Copy image data from an image into a buffer.
Definition: imgutils.c:451
static enum AVPixelFormat get_hw_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
Definition: hw_decode.c:89
const char * fmt
Definition: avisynth_c.h:769
misc image utilities
enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
Look up an AVHWDeviceType by name.
Definition: hwcontext.c:70
hardware decoding through Videotoolbox
Definition: pixfmt.h:296
int size
Definition: avcodec.h:1680
static AVStream * video_stream
AVCodec.
Definition: avcodec.h:3739
Format I/O context.
Definition: avformat.h:1349
uint8_t
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:150
AVOptions.
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1417
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:2354
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:563
uint8_t * data
Definition: avcodec.h:1679
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:101
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:4104
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters...
Definition: imgutils.c:429
int width
Definition: frame.h:259
static AVBufferRef * hw_device_ctx
Definition: hw_decode.c:43
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:163
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:713
int main(int argc, char *argv[])
Definition: hw_decode.c:178
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:558
simple assert() macros that are a bit more flexible than ISO C assert().
#define fail()
Definition: checkasm.h:109
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
Definition: hwcontext.c:433
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:157
static const chunk_decoder decoder[8]
Definition: dfa.c:328
AVFormatContext * ctx
Definition: movenc.c:48
Stream structure.
Definition: avformat.h:889
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:274
static FILE * output_file
Definition: hw_decode.c:45
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:646
Libavcodec external API header.
static int hw_decoder_init(AVCodecContext *ctx, const enum AVHWDeviceType type)
Definition: hw_decode.c:75
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:172
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:232
main external API structure.
Definition: avcodec.h:1761
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:618
static int decode_write(AVCodecContext *avctx, AVPacket *packet)
Definition: hw_decode.c:103
static enum AVPixelFormat find_fmt_by_hw_type(const enum AVHWDeviceType type)
Definition: hw_decode.c:47
GLint GLenum type
Definition: opengl_enc.c:105
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
callback to negotiate the pixelFormat
Definition: avcodec.h:2039
HW acceleration through VDPAU, Picture.data[3] contains a VdpVideoSurface.
Definition: pixfmt.h:209
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:627
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1713
HW decoding through DXVA2, Picture.data[3] contains a LPDIRECT3DSURFACE9 pointer. ...
Definition: pixfmt.h:148
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:266
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:215
Hardware surfaces for Direct3D11.
Definition: pixfmt.h:327
A reference to a data buffer.
Definition: buffer.h:81
Main libavformat public API header.
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:44
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3498
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:4339
AVHWDeviceType
Definition: hwcontext.h:27
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:510
int height
Definition: frame.h:259
#define av_freep(p)
AVCodecParameters * codecpar
Definition: avformat.h:1252
int stream_index
Definition: avcodec.h:1681
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:3668
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1656
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:390
GLuint buffer
Definition: opengl_enc.c:102