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extract_mvs.c
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1 /*
2  * Copyright (c) 2012 Stefano Sabatini
3  * Copyright (c) 2014 Clément Bœsch
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy
6  * of this software and associated documentation files (the "Software"), to deal
7  * in the Software without restriction, including without limitation the rights
8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9  * copies of the Software, and to permit persons to whom the Software is
10  * furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21  * THE SOFTWARE.
22  */
23 
25 #include <libavformat/avformat.h>
26 
30 static const char *src_filename = NULL;
31 
32 static int video_stream_idx = -1;
33 static AVFrame *frame = NULL;
34 static int video_frame_count = 0;
35 
36 static int decode_packet(const AVPacket *pkt)
37 {
38  int ret = avcodec_send_packet(video_dec_ctx, pkt);
39  if (ret < 0) {
40  fprintf(stderr, "Error while sending a packet to the decoder: %s\n", av_err2str(ret));
41  return ret;
42  }
43 
44  while (ret >= 0) {
45  ret = avcodec_receive_frame(video_dec_ctx, frame);
46  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
47  break;
48  } else if (ret < 0) {
49  fprintf(stderr, "Error while receiving a frame from the decoder: %s\n", av_err2str(ret));
50  return ret;
51  }
52 
53  if (ret >= 0) {
54  int i;
55  AVFrameSideData *sd;
56 
59  if (sd) {
60  const AVMotionVector *mvs = (const AVMotionVector *)sd->data;
61  for (i = 0; i < sd->size / sizeof(*mvs); i++) {
62  const AVMotionVector *mv = &mvs[i];
63  printf("%d,%2d,%2d,%2d,%4d,%4d,%4d,%4d,0x%"PRIx64"\n",
65  mv->w, mv->h, mv->src_x, mv->src_y,
66  mv->dst_x, mv->dst_y, mv->flags);
67  }
68  }
69  av_frame_unref(frame);
70  }
71  }
72 
73  return 0;
74 }
75 
77 {
78  int ret;
79  AVStream *st;
81  AVCodec *dec = NULL;
83 
84  ret = av_find_best_stream(fmt_ctx, type, -1, -1, &dec, 0);
85  if (ret < 0) {
86  fprintf(stderr, "Could not find %s stream in input file '%s'\n",
88  return ret;
89  } else {
90  int stream_idx = ret;
91  st = fmt_ctx->streams[stream_idx];
92 
93  dec_ctx = avcodec_alloc_context3(dec);
94  if (!dec_ctx) {
95  fprintf(stderr, "Failed to allocate codec\n");
96  return AVERROR(EINVAL);
97  }
98 
99  ret = avcodec_parameters_to_context(dec_ctx, st->codecpar);
100  if (ret < 0) {
101  fprintf(stderr, "Failed to copy codec parameters to codec context\n");
102  return ret;
103  }
104 
105  /* Init the video decoder */
106  av_dict_set(&opts, "flags2", "+export_mvs", 0);
107  if ((ret = avcodec_open2(dec_ctx, dec, &opts)) < 0) {
108  fprintf(stderr, "Failed to open %s codec\n",
110  return ret;
111  }
112 
113  video_stream_idx = stream_idx;
114  video_stream = fmt_ctx->streams[video_stream_idx];
115  video_dec_ctx = dec_ctx;
116  }
117 
118  return 0;
119 }
120 
121 int main(int argc, char **argv)
122 {
123  int ret = 0;
124  AVPacket pkt = { 0 };
125 
126  if (argc != 2) {
127  fprintf(stderr, "Usage: %s <video>\n", argv[0]);
128  exit(1);
129  }
130  src_filename = argv[1];
131 
132  if (avformat_open_input(&fmt_ctx, src_filename, NULL, NULL) < 0) {
133  fprintf(stderr, "Could not open source file %s\n", src_filename);
134  exit(1);
135  }
136 
137  if (avformat_find_stream_info(fmt_ctx, NULL) < 0) {
138  fprintf(stderr, "Could not find stream information\n");
139  exit(1);
140  }
141 
143 
144  av_dump_format(fmt_ctx, 0, src_filename, 0);
145 
146  if (!video_stream) {
147  fprintf(stderr, "Could not find video stream in the input, aborting\n");
148  ret = 1;
149  goto end;
150  }
151 
152  frame = av_frame_alloc();
153  if (!frame) {
154  fprintf(stderr, "Could not allocate frame\n");
155  ret = AVERROR(ENOMEM);
156  goto end;
157  }
158 
159  printf("framenum,source,blockw,blockh,srcx,srcy,dstx,dsty,flags\n");
160 
161  /* read frames from the file */
162  while (av_read_frame(fmt_ctx, &pkt) >= 0) {
163  if (pkt.stream_index == video_stream_idx)
164  ret = decode_packet(&pkt);
165  av_packet_unref(&pkt);
166  if (ret < 0)
167  break;
168  }
169 
170  /* flush cached frames */
172 
173 end:
174  avcodec_free_context(&video_dec_ctx);
175  avformat_close_input(&fmt_ctx);
176  av_frame_free(&frame);
177  return ret < 0;
178 }
#define NULL
Definition: coverity.c:32
static AVFrame * frame
Definition: extract_mvs.c:33
This structure describes decoded (raw) audio or video data.
Definition: frame.h:226
int16_t src_x
Absolute source position.
Definition: motion_vector.h:38
int main(int argc, char **argv)
Definition: extract_mvs.c:121
static AVPacket pkt
static int video_stream_idx
Definition: extract_mvs.c:32
AVCodec.
Definition: avcodec.h:3441
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:734
Format I/O context.
Definition: avformat.h:1351
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int16_t dst_x
Absolute destination position.
Definition: motion_vector.h:42
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
Structure to hold side data for an AVFrame.
Definition: frame.h:188
int32_t source
Where the current macroblock comes from; negative value when it comes from the past, positive value when it comes from the future.
Definition: motion_vector.h:30
#define AVERROR_EOF
End of file.
Definition: error.h:55
void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output)
Print detailed information about the input or output format, such as duration, bitrate, streams, container, programs, metadata, side data, codec and time base.
Definition: dump.c:563
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
static AVStream * video_stream
Definition: extract_mvs.c:29
#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
uint8_t w
Width and height of the block.
Definition: motion_vector.h:34
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:740
static int video_frame_count
Definition: extract_mvs.c:34
static AVFormatContext * fmt_ctx
Definition: extract_mvs.c:27
static AVCodecContext * video_dec_ctx
Definition: extract_mvs.c:28
AVDictionary * opts
Definition: movenc.c:50
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:156
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
Motion vectors exported by some codecs (on demand through the export_mvs flag set in the libavcodec A...
Definition: frame.h:96
Stream structure.
Definition: avformat.h:874
static const int8_t mv[256][2]
Definition: 4xm.c:77
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:677
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
main external API structure.
Definition: avcodec.h:1540
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:598
uint8_t * data
Definition: frame.h:190
GLint GLenum type
Definition: opengl_enc.c:105
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
AVMediaType
Definition: avutil.h:199
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
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
const char * av_get_media_type_string(enum AVMediaType media_type)
Return a string describing the media_type enum, NULL if media_type is unknown.
Definition: utils.c:76
Main libavformat public API header.
uint64_t flags
Extra flag information.
Definition: motion_vector.h:47
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3564
static AVCodecContext * dec_ctx
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4427
static int open_codec_context(AVFormatContext *fmt_ctx, enum AVMediaType type)
Definition: extract_mvs.c:76
static int decode_packet(const AVPacket *pkt)
Definition: extract_mvs.c:36
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
static const char * src_filename
Definition: extract_mvs.c:30
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
int stream_index
Definition: avcodec.h:1454
This structure stores compressed data.
Definition: avcodec.h:1429
for(j=16;j >0;--j)