FFmpeg
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:295
int16_t src_x
Absolute source position.
Definition: motion_vector.h:38
int main(int argc, char **argv)
Definition: extract_mvs.c:121
GLint GLenum type
Definition: opengl_enc.c:104
int avformat_open_input(AVFormatContext **ps, const char *url, ff_const59 AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:539
static AVPacket pkt
static int video_stream_idx
Definition: extract_mvs.c:32
AVCodec.
Definition: avcodec.h:3492
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:734
Format I/O context.
Definition: avformat.h:1358
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:1426
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:2110
Structure to hold side data for an AVFrame.
Definition: frame.h:201
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:578
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:4226
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
static AVStream * video_stream
Definition: extract_mvs.c:29
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:739
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:881
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:676
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:1568
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
uint8_t * data
Definition: frame.h:203
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:548
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1777
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:3600
static AVCodecContext * dec_ctx
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4471
static int open_codec_context(AVFormatContext *fmt_ctx, enum AVMediaType type)
Definition: extract_mvs.c:76
printf("static const uint8_t my_array[100] = {\n")
static int decode_packet(const AVPacket *pkt)
Definition: extract_mvs.c:36
static const char * src_filename
Definition: extract_mvs.c:30
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1482
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
This structure stores compressed data.
Definition: avcodec.h:1457
for(j=16;j >0;--j)