FFmpeg
vf_find_rect.c
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1 /*
2  * Copyright (c) 2014-2015 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20 
21 /**
22  * @todo switch to dualinput
23  */
24 
25 #include "libavutil/avassert.h"
26 #include "libavutil/imgutils.h"
27 #include "libavutil/opt.h"
28 #include "internal.h"
29 
30 #include "lavfutils.h"
31 
32 #define MAX_MIPMAPS 5
33 
34 typedef struct FOCContext {
35  AVClass *class;
36  float threshold;
37  int mipmaps;
38  int xmin, ymin, xmax, ymax;
39  char *obj_filename;
40  int last_x, last_y;
44 } FOCContext;
45 
46 #define OFFSET(x) offsetof(FOCContext, x)
47 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
48 static const AVOption find_rect_options[] = {
49  { "object", "object bitmap filename", OFFSET(obj_filename), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
50  { "threshold", "set threshold", OFFSET(threshold), AV_OPT_TYPE_FLOAT, {.dbl = 0.5}, 0, 1.0, FLAGS },
51  { "mipmaps", "set mipmaps", OFFSET(mipmaps), AV_OPT_TYPE_INT, {.i64 = 3}, 1, MAX_MIPMAPS, FLAGS },
52  { "xmin", "", OFFSET(xmin), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
53  { "ymin", "", OFFSET(ymin), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
54  { "xmax", "", OFFSET(xmax), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
55  { "ymax", "", OFFSET(ymax), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
56  { NULL }
57 };
58 
59 AVFILTER_DEFINE_CLASS(find_rect);
60 
62 {
63  static const enum AVPixelFormat pix_fmts[] = {
67  };
68 
69  return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
70 }
71 
73 {
74  int x, y;
76  uint8_t *src, *dst;
77  if (!frame)
78  return NULL;
79 
80  frame->format = in->format;
81  frame->width = (in->width + 1) / 2;
82  frame->height = (in->height+ 1) / 2;
83 
84  if (av_frame_get_buffer(frame, 32) < 0) {
85  av_frame_free(&frame);
86  return NULL;
87  }
88  src = in ->data[0];
89  dst = frame->data[0];
90 
91  for(y = 0; y < frame->height; y++) {
92  for(x = 0; x < frame->width; x++) {
93  dst[x] = ( src[2*x+0]
94  + src[2*x+1]
95  + src[2*x+0 + in->linesize[0]]
96  + src[2*x+1 + in->linesize[0]]
97  + 2) >> 2;
98  }
99  src += 2*in->linesize[0];
100  dst += frame->linesize[0];
101  }
102  return frame;
103 }
104 
105 static float compare(const AVFrame *haystack, const AVFrame *obj, int offx, int offy)
106 {
107  int x,y;
108  int o_sum_v = 0;
109  int h_sum_v = 0;
110  int64_t oo_sum_v = 0;
111  int64_t hh_sum_v = 0;
112  int64_t oh_sum_v = 0;
113  float c;
114  int n = obj->height * obj->width;
115  const uint8_t *odat = obj ->data[0];
116  const uint8_t *hdat = haystack->data[0] + offx + offy * haystack->linesize[0];
117  int64_t o_sigma, h_sigma;
118 
119  for(y = 0; y < obj->height; y++) {
120  for(x = 0; x < obj->width; x++) {
121  int o_v = odat[x];
122  int h_v = hdat[x];
123  o_sum_v += o_v;
124  h_sum_v += h_v;
125  oo_sum_v += o_v * o_v;
126  hh_sum_v += h_v * h_v;
127  oh_sum_v += o_v * h_v;
128  }
129  odat += obj->linesize[0];
130  hdat += haystack->linesize[0];
131  }
132  o_sigma = n*oo_sum_v - o_sum_v*(int64_t)o_sum_v;
133  h_sigma = n*hh_sum_v - h_sum_v*(int64_t)h_sum_v;
134 
135  if (o_sigma == 0 || h_sigma == 0)
136  return 1.0;
137 
138  c = (n*oh_sum_v - o_sum_v*(int64_t)h_sum_v) / (sqrt(o_sigma)*sqrt(h_sigma));
139 
140  return 1 - fabs(c);
141 }
142 
144 {
145  AVFilterContext *ctx = inlink->dst;
146  FOCContext *foc = ctx->priv;
147 
148  if (foc->xmax <= 0)
149  foc->xmax = inlink->w - foc->obj_frame->width;
150  if (foc->ymax <= 0)
151  foc->ymax = inlink->h - foc->obj_frame->height;
152 
153  return 0;
154 }
155 
156 static float search(FOCContext *foc, int pass, int maxpass, int xmin, int xmax, int ymin, int ymax, int *best_x, int *best_y, float best_score)
157 {
158  int x, y;
159 
160  if (pass + 1 <= maxpass) {
161  int sub_x, sub_y;
162  search(foc, pass+1, maxpass, xmin>>1, (xmax+1)>>1, ymin>>1, (ymax+1)>>1, &sub_x, &sub_y, 1.0);
163  xmin = FFMAX(xmin, 2*sub_x - 4);
164  xmax = FFMIN(xmax, 2*sub_x + 4);
165  ymin = FFMAX(ymin, 2*sub_y - 4);
166  ymax = FFMIN(ymax, 2*sub_y + 4);
167  }
168 
169  for (y = ymin; y <= ymax; y++) {
170  for (x = xmin; x <= xmax; x++) {
171  float score = compare(foc->haystack_frame[pass], foc->needle_frame[pass], x, y);
172  av_assert0(score != 0);
173  if (score < best_score) {
174  best_score = score;
175  *best_x = x;
176  *best_y = y;
177  }
178  }
179  }
180  return best_score;
181 }
182 
184 {
185  AVFilterContext *ctx = inlink->dst;
186  FOCContext *foc = ctx->priv;
187  float best_score;
188  int best_x, best_y;
189  int i;
190 
191  foc->haystack_frame[0] = av_frame_clone(in);
192  for (i=1; i<foc->mipmaps; i++) {
193  foc->haystack_frame[i] = downscale(foc->haystack_frame[i-1]);
194  }
195 
196  best_score = search(foc, 0, 0,
197  FFMAX(foc->xmin, foc->last_x - 8),
198  FFMIN(foc->xmax, foc->last_x + 8),
199  FFMAX(foc->ymin, foc->last_y - 8),
200  FFMIN(foc->ymax, foc->last_y + 8),
201  &best_x, &best_y, 1.0);
202 
203  best_score = search(foc, 0, foc->mipmaps - 1, foc->xmin, foc->xmax, foc->ymin, foc->ymax,
204  &best_x, &best_y, best_score);
205 
206  for (i=0; i<MAX_MIPMAPS; i++) {
207  av_frame_free(&foc->haystack_frame[i]);
208  }
209 
210  if (best_score > foc->threshold) {
211  return ff_filter_frame(ctx->outputs[0], in);
212  }
213 
214  av_log(ctx, AV_LOG_DEBUG, "Found at %d %d score %f\n", best_x, best_y, best_score);
215  foc->last_x = best_x;
216  foc->last_y = best_y;
217 
219 
220  av_dict_set_int(&in->metadata, "lavfi.rect.w", foc->obj_frame->width, 0);
221  av_dict_set_int(&in->metadata, "lavfi.rect.h", foc->obj_frame->height, 0);
222  av_dict_set_int(&in->metadata, "lavfi.rect.x", best_x, 0);
223  av_dict_set_int(&in->metadata, "lavfi.rect.y", best_y, 0);
224 
225  return ff_filter_frame(ctx->outputs[0], in);
226 }
227 
229 {
230  FOCContext *foc = ctx->priv;
231  int i;
232 
233  for (i = 0; i < MAX_MIPMAPS; i++) {
234  av_frame_free(&foc->needle_frame[i]);
235  av_frame_free(&foc->haystack_frame[i]);
236  }
237 
238  if (foc->obj_frame)
239  av_freep(&foc->obj_frame->data[0]);
240  av_frame_free(&foc->obj_frame);
241 }
242 
244 {
245  FOCContext *foc = ctx->priv;
246  int ret, i;
247 
248  if (!foc->obj_filename) {
249  av_log(ctx, AV_LOG_ERROR, "object filename not set\n");
250  return AVERROR(EINVAL);
251  }
252 
253  foc->obj_frame = av_frame_alloc();
254  if (!foc->obj_frame)
255  return AVERROR(ENOMEM);
256 
257  if ((ret = ff_load_image(foc->obj_frame->data, foc->obj_frame->linesize,
258  &foc->obj_frame->width, &foc->obj_frame->height,
259  &foc->obj_frame->format, foc->obj_filename, ctx)) < 0)
260  return ret;
261 
262  if (foc->obj_frame->format != AV_PIX_FMT_GRAY8) {
263  av_log(ctx, AV_LOG_ERROR, "object image is not a grayscale image\n");
264  return AVERROR(EINVAL);
265  }
266 
267  foc->needle_frame[0] = av_frame_clone(foc->obj_frame);
268  for (i = 1; i < foc->mipmaps; i++) {
269  foc->needle_frame[i] = downscale(foc->needle_frame[i-1]);
270  if (!foc->needle_frame[i])
271  return AVERROR(ENOMEM);
272  }
273 
274  return 0;
275 }
276 
277 static const AVFilterPad foc_inputs[] = {
278  {
279  .name = "default",
280  .type = AVMEDIA_TYPE_VIDEO,
281  .config_props = config_input,
282  .filter_frame = filter_frame,
283  },
284  { NULL }
285 };
286 
287 static const AVFilterPad foc_outputs[] = {
288  {
289  .name = "default",
290  .type = AVMEDIA_TYPE_VIDEO,
291  },
292  { NULL }
293 };
294 
296  .name = "find_rect",
297  .description = NULL_IF_CONFIG_SMALL("Find a user specified object."),
298  .priv_size = sizeof(FOCContext),
299  .init = init,
300  .uninit = uninit,
302  .inputs = foc_inputs,
303  .outputs = foc_outputs,
304  .priv_class = &find_rect_class,
305 };
static float compare(const AVFrame *haystack, const AVFrame *obj, int offx, int offy)
Definition: vf_find_rect.c:105
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
misc image utilities
AVFilter ff_vf_find_rect
Definition: vf_find_rect.c:295
#define OFFSET(x)
Definition: vf_find_rect.c:46
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: vf_find_rect.c:183
#define src
Definition: vp8dsp.c:254
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
const char * name
Pad name.
Definition: internal.h:60
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
static float search(FOCContext *foc, int pass, int maxpass, int xmin, int xmax, int ymin, int ymax, int *best_x, int *best_y, float best_score)
Definition: vf_find_rect.c:156
AVOptions.
#define FLAGS
Definition: vf_find_rect.c:47
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVFrame * obj_frame
Definition: vf_find_rect.c:41
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_find_rect.c:228
AVDictionary * metadata
metadata.
Definition: frame.h:581
static const AVFilterPad foc_outputs[]
Definition: vf_find_rect.c:287
static AVFrame * downscale(AVFrame *in)
Definition: vf_find_rect.c:72
#define MAX_MIPMAPS
Definition: vf_find_rect.c:32
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
static const AVFilterPad foc_inputs[]
Definition: vf_find_rect.c:277
static const AVOption find_rect_options[]
Definition: vf_find_rect.c:48
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
int width
Definition: frame.h:353
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:568
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
simple assert() macros that are a bit more flexible than ISO C assert().
#define FFMAX(a, b)
Definition: common.h:94
#define pass
Definition: fft_template.c:619
#define FFMIN(a, b)
Definition: common.h:96
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:78
AVFormatContext * ctx
Definition: movenc.c:48
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
int ff_load_image(uint8_t *data[4], int linesize[4], int *w, int *h, enum AVPixelFormat *pix_fmt, const char *filename, void *log_ctx)
Load image from filename and put the resulting image in data.
Definition: lavfutils.c:24
int n
Definition: avisynth_c.h:760
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:540
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:368
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
AVFrame * haystack_frame[MAX_MIPMAPS]
Definition: vf_find_rect.c:43
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 inputs
static av_cold int init(AVFilterContext *ctx)
Definition: vf_find_rect.c:243
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31))))#define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac){}void ff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map){AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);return NULL;}return ac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;}int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){int use_generic=1;int len=in->nb_samples;int p;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%d samples - audio_convert: %s to %s (dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
Describe the class of an AVClass context structure.
Definition: log.h:67
AVFILTER_DEFINE_CLASS(find_rect)
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
int av_frame_get_buffer(AVFrame *frame, int align)
Allocate new buffer(s) for audio or video data.
Definition: frame.c:324
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:611
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
Y , 8bpp.
Definition: pixfmt.h:74
float threshold
Definition: vf_find_rect.c:36
int av_dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags)
Convenience wrapper for av_dict_set that converts the value to a string and stores it...
Definition: dict.c:147
static int config_input(AVFilterLink *inlink)
Definition: vf_find_rect.c:143
static int query_formats(AVFilterContext *ctx)
Definition: vf_find_rect.c:61
An instance of a filter.
Definition: avfilter.h:338
int height
Definition: frame.h:353
#define av_freep(p)
char * obj_filename
Definition: vf_find_rect.c:39
internal API functions
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
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
Miscellaneous utilities which make use of the libavformat library.
AVFrame * needle_frame[MAX_MIPMAPS]
Definition: vf_find_rect.c:42