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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  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 /**
27  * @file
28  * HW-Accelerated decoding example.
29  *
30  * @example hw_decode.c
31  * This example shows how to do HW-accelerated decoding with output
32  * frames from the HW video surfaces.
33  */
34 
35 #include <stdio.h>
36 
37 #include <libavcodec/avcodec.h>
38 #include <libavformat/avformat.h>
39 #include <libavutil/pixdesc.h>
40 #include <libavutil/hwcontext.h>
41 #include <libavutil/opt.h>
42 #include <libavutil/avassert.h>
43 #include <libavutil/imgutils.h>
44 
47 static FILE *output_file = NULL;
48 
50 {
51  int err = 0;
52 
53  if ((err = av_hwdevice_ctx_create(&hw_device_ctx, type,
54  NULL, NULL, 0)) < 0) {
55  fprintf(stderr, "Failed to create specified HW device.\n");
56  return err;
57  }
58  ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
59 
60  return err;
61 }
62 
64  const enum AVPixelFormat *pix_fmts)
65 {
66  const enum AVPixelFormat *p;
67 
68  for (p = pix_fmts; *p != -1; p++) {
69  if (*p == hw_pix_fmt)
70  return *p;
71  }
72 
73  fprintf(stderr, "Failed to get HW surface format.\n");
74  return AV_PIX_FMT_NONE;
75 }
76 
77 static int decode_write(AVCodecContext *avctx, AVPacket *packet)
78 {
79  AVFrame *frame = NULL, *sw_frame = NULL;
80  AVFrame *tmp_frame = NULL;
81  uint8_t *buffer = NULL;
82  int size;
83  int ret = 0;
84 
85  ret = avcodec_send_packet(avctx, packet);
86  if (ret < 0) {
87  fprintf(stderr, "Error during decoding\n");
88  return ret;
89  }
90 
91  while (1) {
92  if (!(frame = av_frame_alloc()) || !(sw_frame = av_frame_alloc())) {
93  fprintf(stderr, "Can not alloc frame\n");
94  ret = AVERROR(ENOMEM);
95  goto fail;
96  }
97 
98  ret = avcodec_receive_frame(avctx, frame);
99  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
100  av_frame_free(&frame);
101  av_frame_free(&sw_frame);
102  return 0;
103  } else if (ret < 0) {
104  fprintf(stderr, "Error while decoding\n");
105  goto fail;
106  }
107 
108  if (frame->format == hw_pix_fmt) {
109  /* retrieve data from GPU to CPU */
110  if ((ret = av_hwframe_transfer_data(sw_frame, frame, 0)) < 0) {
111  fprintf(stderr, "Error transferring the data to system memory\n");
112  goto fail;
113  }
114  tmp_frame = sw_frame;
115  } else
116  tmp_frame = frame;
117 
118  size = av_image_get_buffer_size(tmp_frame->format, tmp_frame->width,
119  tmp_frame->height, 1);
120  buffer = av_malloc(size);
121  if (!buffer) {
122  fprintf(stderr, "Can not alloc buffer\n");
123  ret = AVERROR(ENOMEM);
124  goto fail;
125  }
126  ret = av_image_copy_to_buffer(buffer, size,
127  (const uint8_t * const *)tmp_frame->data,
128  (const int *)tmp_frame->linesize, tmp_frame->format,
129  tmp_frame->width, tmp_frame->height, 1);
130  if (ret < 0) {
131  fprintf(stderr, "Can not copy image to buffer\n");
132  goto fail;
133  }
134 
135  if ((ret = fwrite(buffer, 1, size, output_file)) < 0) {
136  fprintf(stderr, "Failed to dump raw data.\n");
137  goto fail;
138  }
139 
140  fail:
141  av_frame_free(&frame);
142  av_frame_free(&sw_frame);
143  av_freep(&buffer);
144  if (ret < 0)
145  return ret;
146  }
147 }
148 
149 int main(int argc, char *argv[])
150 {
151  AVFormatContext *input_ctx = NULL;
152  int video_stream, ret;
153  AVStream *video = NULL;
155  AVCodec *decoder = NULL;
156  AVPacket packet;
157  enum AVHWDeviceType type;
158  int i;
159 
160  if (argc < 4) {
161  fprintf(stderr, "Usage: %s <device type> <input file> <output file>\n", argv[0]);
162  return -1;
163  }
164 
165  type = av_hwdevice_find_type_by_name(argv[1]);
166  if (type == AV_HWDEVICE_TYPE_NONE) {
167  fprintf(stderr, "Device type %s is not supported.\n", argv[1]);
168  fprintf(stderr, "Available device types:");
169  while((type = av_hwdevice_iterate_types(type)) != AV_HWDEVICE_TYPE_NONE)
170  fprintf(stderr, " %s", av_hwdevice_get_type_name(type));
171  fprintf(stderr, "\n");
172  return -1;
173  }
174 
175  /* open the input file */
176  if (avformat_open_input(&input_ctx, argv[2], NULL, NULL) != 0) {
177  fprintf(stderr, "Cannot open input file '%s'\n", argv[2]);
178  return -1;
179  }
180 
181  if (avformat_find_stream_info(input_ctx, NULL) < 0) {
182  fprintf(stderr, "Cannot find input stream information.\n");
183  return -1;
184  }
185 
186  /* find the video stream information */
187  ret = av_find_best_stream(input_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
188  if (ret < 0) {
189  fprintf(stderr, "Cannot find a video stream in the input file\n");
190  return -1;
191  }
192  video_stream = ret;
193 
194  for (i = 0;; i++) {
195  const AVCodecHWConfig *config = avcodec_get_hw_config(decoder, i);
196  if (!config) {
197  fprintf(stderr, "Decoder %s does not support device type %s.\n",
198  decoder->name, av_hwdevice_get_type_name(type));
199  return -1;
200  }
202  config->device_type == type) {
203  hw_pix_fmt = config->pix_fmt;
204  break;
205  }
206  }
207 
208  if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
209  return AVERROR(ENOMEM);
210 
211  video = input_ctx->streams[video_stream];
212  if (avcodec_parameters_to_context(decoder_ctx, video->codecpar) < 0)
213  return -1;
214 
215  decoder_ctx->get_format = get_hw_format;
216 
217  if (hw_decoder_init(decoder_ctx, type) < 0)
218  return -1;
219 
220  if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0) {
221  fprintf(stderr, "Failed to open codec for stream #%u\n", video_stream);
222  return -1;
223  }
224 
225  /* open the file to dump raw data */
226  output_file = fopen(argv[3], "w+");
227 
228  /* actual decoding and dump the raw data */
229  while (ret >= 0) {
230  if ((ret = av_read_frame(input_ctx, &packet)) < 0)
231  break;
232 
233  if (video_stream == packet.stream_index)
234  ret = decode_write(decoder_ctx, &packet);
235 
236  av_packet_unref(&packet);
237  }
238 
239  /* flush the decoder */
240  packet.data = NULL;
241  packet.size = 0;
242  ret = decode_write(decoder_ctx, &packet);
243  av_packet_unref(&packet);
244 
245  if (output_file)
246  fclose(output_file);
247  avcodec_free_context(&decoder_ctx);
248  avformat_close_input(&input_ctx);
249  av_buffer_unref(&hw_device_ctx);
250 
251  return 0;
252 }
#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:226
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:453
static enum AVPixelFormat get_hw_format(AVCodecContext *ctx, const enum AVPixelFormat *pix_fmts)
Definition: hw_decode.c:63
misc image utilities
enum AVHWDeviceType av_hwdevice_find_type_by_name(const char *name)
Look up an AVHWDeviceType by name.
Definition: hwcontext.c:78
static AVCodecContext * decoder_ctx
int size
Definition: avcodec.h:1453
static AVStream * video_stream
AVCodec.
Definition: avcodec.h:3441
Format I/O context.
Definition: avformat.h:1351
uint8_t
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
AVOptions.
enum AVPixelFormat pix_fmt
A hardware pixel format which the codec can use.
Definition: avcodec.h:3419
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
ptrdiff_t size
Definition: opengl_enc.c:101
The codec supports this format via the hw_device_ctx interface.
Definition: avcodec.h:3387
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
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:431
int width
Definition: frame.h:284
static AVBufferRef * hw_device_ctx
Definition: hw_decode.c:45
#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:202
int methods
Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible setup methods which can be used...
Definition: avcodec.h:3424
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:740
int main(int argc, char *argv[])
Definition: hw_decode.c:149
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
Definition: avcodec.h:3448
#define fail()
Definition: checkasm.h:117
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
Definition: hwcontext.c:439
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
AVFormatContext * ctx
Definition: movenc.c:48
Stream structure.
Definition: avformat.h:874
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:299
static FILE * output_file
Definition: hw_decode.c:47
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.
static int hw_decoder_init(AVCodecContext *ctx, const enum AVHWDeviceType type)
Definition: hw_decode.c:49
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
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:257
const AVCodecHWConfig * avcodec_get_hw_config(const AVCodec *codec, int index)
Retrieve supported hardware configurations for a codec.
Definition: utils.c:1761
main external API structure.
Definition: avcodec.h:1540
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:598
static int decode_write(AVCodecContext *avctx, AVPacket *packet)
Definition: hw_decode.c:77
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:1792
const char * av_hwdevice_get_type_name(enum AVHWDeviceType type)
Get the string name of an AVHWDeviceType.
Definition: hwcontext.c:88
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:542
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
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:240
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:46
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 avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4427
enum AVHWDeviceType av_hwdevice_iterate_types(enum AVHWDeviceType prev)
Iterate over supported device types.
Definition: hwcontext.c:97
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:537
int height
Definition: frame.h:284
#define av_freep(p)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
enum AVHWDeviceType device_type
The device type associated with the configuration.
Definition: avcodec.h:3431
int stream_index
Definition: avcodec.h:1454
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
GLuint buffer
Definition: opengl_enc.c:102