FFmpeg
vf_edgedetect.c
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1 /*
2  * Copyright (c) 2012-2014 Clément Bœsch <u pkh me>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (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 GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * Edge detection filter
24  *
25  * @see https://en.wikipedia.org/wiki/Canny_edge_detector
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/opt.h"
31 #include "avfilter.h"
32 #include "formats.h"
33 #include "internal.h"
34 #include "video.h"
35 
36 #define PLANE_R 0x4
37 #define PLANE_G 0x1
38 #define PLANE_B 0x2
39 #define PLANE_Y 0x1
40 #define PLANE_U 0x2
41 #define PLANE_V 0x4
42 #define PLANE_A 0x8
43 
44 enum FilterMode {
49 };
50 
51 struct plane_info {
53  uint16_t *gradients;
54  char *directions;
55  int width, height;
56 };
57 
58 typedef struct EdgeDetectContext {
59  const AVClass *class;
60  struct plane_info planes[3];
62  int nb_planes;
63  double low, high;
64  uint8_t low_u8, high_u8;
65  int mode;
67 
68 #define OFFSET(x) offsetof(EdgeDetectContext, x)
69 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
70 static const AVOption edgedetect_options[] = {
71  { "high", "set high threshold", OFFSET(high), AV_OPT_TYPE_DOUBLE, {.dbl=50/255.}, 0, 1, FLAGS },
72  { "low", "set low threshold", OFFSET(low), AV_OPT_TYPE_DOUBLE, {.dbl=20/255.}, 0, 1, FLAGS },
73  { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_WIRES}, 0, NB_MODE-1, FLAGS, "mode" },
74  { "wires", "white/gray wires on black", 0, AV_OPT_TYPE_CONST, {.i64=MODE_WIRES}, INT_MIN, INT_MAX, FLAGS, "mode" },
75  { "colormix", "mix colors", 0, AV_OPT_TYPE_CONST, {.i64=MODE_COLORMIX}, INT_MIN, INT_MAX, FLAGS, "mode" },
76  { "canny", "detect edges on planes", 0, AV_OPT_TYPE_CONST, {.i64=MODE_CANNY}, INT_MIN, INT_MAX, FLAGS, "mode" },
77  { "planes", "set planes to filter", OFFSET(filter_planes), AV_OPT_TYPE_FLAGS, {.i64=7}, 1, 0x7, FLAGS, "flags" },
78  { "y", "filter luma plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_Y}, 0, 0, FLAGS, "flags" },
79  { "u", "filter u plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_U}, 0, 0, FLAGS, "flags" },
80  { "v", "filter v plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_V}, 0, 0, FLAGS, "flags" },
81  { "r", "filter red plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_R}, 0, 0, FLAGS, "flags" },
82  { "g", "filter green plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_G}, 0, 0, FLAGS, "flags" },
83  { "b", "filter blue plane", 0, AV_OPT_TYPE_CONST, {.i64=PLANE_B}, 0, 0, FLAGS, "flags" },
84  { NULL }
85 };
86 
88 
90 {
92 
93  edgedetect->low_u8 = edgedetect->low * 255. + .5;
94  edgedetect->high_u8 = edgedetect->high * 255. + .5;
95  return 0;
96 }
97 
99 {
100  const EdgeDetectContext *edgedetect = ctx->priv;
101  static const enum AVPixelFormat wires_pix_fmts[] = {AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE};
102  static const enum AVPixelFormat canny_pix_fmts[] = {AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_GBRP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE};
103  static const enum AVPixelFormat colormix_pix_fmts[] = {AV_PIX_FMT_GBRP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE};
104  AVFilterFormats *fmts_list;
105  const enum AVPixelFormat *pix_fmts = NULL;
106 
107  if (edgedetect->mode == MODE_WIRES) {
108  pix_fmts = wires_pix_fmts;
109  } else if (edgedetect->mode == MODE_COLORMIX) {
110  pix_fmts = colormix_pix_fmts;
111  } else if (edgedetect->mode == MODE_CANNY) {
112  pix_fmts = canny_pix_fmts;
113  } else {
114  av_assert0(0);
115  }
116  fmts_list = ff_make_format_list(pix_fmts);
117  if (!fmts_list)
118  return AVERROR(ENOMEM);
119  return ff_set_common_formats(ctx, fmts_list);
120 }
121 
123 {
124  int p;
125  AVFilterContext *ctx = inlink->dst;
128 
129  edgedetect->nb_planes = inlink->format == AV_PIX_FMT_GRAY8 ? 1 : 3;
130  for (p = 0; p < edgedetect->nb_planes; p++) {
131  struct plane_info *plane = &edgedetect->planes[p];
132  int vsub = p ? desc->log2_chroma_h : 0;
133  int hsub = p ? desc->log2_chroma_w : 0;
134 
135  plane->width = AV_CEIL_RSHIFT(inlink->w, hsub);
136  plane->height = AV_CEIL_RSHIFT(inlink->h, vsub);
137  plane->tmpbuf = av_malloc(plane->width * plane->height);
138  plane->gradients = av_calloc(plane->width * plane->height, sizeof(*plane->gradients));
139  plane->directions = av_malloc(plane->width * plane->height);
140  if (!plane->tmpbuf || !plane->gradients || !plane->directions)
141  return AVERROR(ENOMEM);
142  }
143  return 0;
144 }
145 
146 static void gaussian_blur(AVFilterContext *ctx, int w, int h,
147  uint8_t *dst, int dst_linesize,
148  const uint8_t *src, int src_linesize)
149 {
150  int i, j;
151 
152  memcpy(dst, src, w); dst += dst_linesize; src += src_linesize;
153  if (h > 1) {
154  memcpy(dst, src, w); dst += dst_linesize; src += src_linesize;
155  }
156  for (j = 2; j < h - 2; j++) {
157  dst[0] = src[0];
158  if (w > 1)
159  dst[1] = src[1];
160  for (i = 2; i < w - 2; i++) {
161  /* Gaussian mask of size 5x5 with sigma = 1.4 */
162  dst[i] = ((src[-2*src_linesize + i-2] + src[2*src_linesize + i-2]) * 2
163  + (src[-2*src_linesize + i-1] + src[2*src_linesize + i-1]) * 4
164  + (src[-2*src_linesize + i ] + src[2*src_linesize + i ]) * 5
165  + (src[-2*src_linesize + i+1] + src[2*src_linesize + i+1]) * 4
166  + (src[-2*src_linesize + i+2] + src[2*src_linesize + i+2]) * 2
167 
168  + (src[ -src_linesize + i-2] + src[ src_linesize + i-2]) * 4
169  + (src[ -src_linesize + i-1] + src[ src_linesize + i-1]) * 9
170  + (src[ -src_linesize + i ] + src[ src_linesize + i ]) * 12
171  + (src[ -src_linesize + i+1] + src[ src_linesize + i+1]) * 9
172  + (src[ -src_linesize + i+2] + src[ src_linesize + i+2]) * 4
173 
174  + src[i-2] * 5
175  + src[i-1] * 12
176  + src[i ] * 15
177  + src[i+1] * 12
178  + src[i+2] * 5) / 159;
179  }
180  if (w > 2)
181  dst[i ] = src[i ];
182  if (w > 3)
183  dst[i + 1] = src[i + 1];
184 
185  dst += dst_linesize;
186  src += src_linesize;
187  }
188  if (h > 2) {
189  memcpy(dst, src, w); dst += dst_linesize; src += src_linesize;
190  }
191  if (h > 3)
192  memcpy(dst, src, w);
193 }
194 
195 enum {
200 };
201 
202 static int get_rounded_direction(int gx, int gy)
203 {
204  /* reference angles:
205  * tan( pi/8) = sqrt(2)-1
206  * tan(3pi/8) = sqrt(2)+1
207  * Gy/Gx is the tangent of the angle (theta), so Gy/Gx is compared against
208  * <ref-angle>, or more simply Gy against <ref-angle>*Gx
209  *
210  * Gx and Gy bounds = [-1020;1020], using 16-bit arithmetic:
211  * round((sqrt(2)-1) * (1<<16)) = 27146
212  * round((sqrt(2)+1) * (1<<16)) = 158218
213  */
214  if (gx) {
215  int tanpi8gx, tan3pi8gx;
216 
217  if (gx < 0)
218  gx = -gx, gy = -gy;
219  gy *= (1 << 16);
220  tanpi8gx = 27146 * gx;
221  tan3pi8gx = 158218 * gx;
222  if (gy > -tan3pi8gx && gy < -tanpi8gx) return DIRECTION_45UP;
223  if (gy > -tanpi8gx && gy < tanpi8gx) return DIRECTION_HORIZONTAL;
224  if (gy > tanpi8gx && gy < tan3pi8gx) return DIRECTION_45DOWN;
225  }
226  return DIRECTION_VERTICAL;
227 }
228 
229 static void sobel(int w, int h,
230  uint16_t *dst, int dst_linesize,
231  int8_t *dir, int dir_linesize,
232  const uint8_t *src, int src_linesize)
233 {
234  int i, j;
235 
236  for (j = 1; j < h - 1; j++) {
237  dst += dst_linesize;
238  dir += dir_linesize;
239  src += src_linesize;
240  for (i = 1; i < w - 1; i++) {
241  const int gx =
242  -1*src[-src_linesize + i-1] + 1*src[-src_linesize + i+1]
243  -2*src[ i-1] + 2*src[ i+1]
244  -1*src[ src_linesize + i-1] + 1*src[ src_linesize + i+1];
245  const int gy =
246  -1*src[-src_linesize + i-1] + 1*src[ src_linesize + i-1]
247  -2*src[-src_linesize + i ] + 2*src[ src_linesize + i ]
248  -1*src[-src_linesize + i+1] + 1*src[ src_linesize + i+1];
249 
250  dst[i] = FFABS(gx) + FFABS(gy);
251  dir[i] = get_rounded_direction(gx, gy);
252  }
253  }
254 }
255 
256 static void non_maximum_suppression(int w, int h,
257  uint8_t *dst, int dst_linesize,
258  const int8_t *dir, int dir_linesize,
259  const uint16_t *src, int src_linesize)
260 {
261  int i, j;
262 
263 #define COPY_MAXIMA(ay, ax, by, bx) do { \
264  if (src[i] > src[(ay)*src_linesize + i+(ax)] && \
265  src[i] > src[(by)*src_linesize + i+(bx)]) \
266  dst[i] = av_clip_uint8(src[i]); \
267 } while (0)
268 
269  for (j = 1; j < h - 1; j++) {
270  dst += dst_linesize;
271  dir += dir_linesize;
272  src += src_linesize;
273  for (i = 1; i < w - 1; i++) {
274  switch (dir[i]) {
275  case DIRECTION_45UP: COPY_MAXIMA( 1, -1, -1, 1); break;
276  case DIRECTION_45DOWN: COPY_MAXIMA(-1, -1, 1, 1); break;
277  case DIRECTION_HORIZONTAL: COPY_MAXIMA( 0, -1, 0, 1); break;
278  case DIRECTION_VERTICAL: COPY_MAXIMA(-1, 0, 1, 0); break;
279  }
280  }
281  }
282 }
283 
284 static void double_threshold(int low, int high, int w, int h,
285  uint8_t *dst, int dst_linesize,
286  const uint8_t *src, int src_linesize)
287 {
288  int i, j;
289 
290  for (j = 0; j < h; j++) {
291  for (i = 0; i < w; i++) {
292  if (src[i] > high) {
293  dst[i] = src[i];
294  continue;
295  }
296 
297  if ((!i || i == w - 1 || !j || j == h - 1) &&
298  src[i] > low &&
299  (src[-src_linesize + i-1] > high ||
300  src[-src_linesize + i ] > high ||
301  src[-src_linesize + i+1] > high ||
302  src[ i-1] > high ||
303  src[ i+1] > high ||
304  src[ src_linesize + i-1] > high ||
305  src[ src_linesize + i ] > high ||
306  src[ src_linesize + i+1] > high))
307  dst[i] = src[i];
308  else
309  dst[i] = 0;
310  }
311  dst += dst_linesize;
312  src += src_linesize;
313  }
314 }
315 
316 static void color_mix(int w, int h,
317  uint8_t *dst, int dst_linesize,
318  const uint8_t *src, int src_linesize)
319 {
320  int i, j;
321 
322  for (j = 0; j < h; j++) {
323  for (i = 0; i < w; i++)
324  dst[i] = (dst[i] + src[i]) >> 1;
325  dst += dst_linesize;
326  src += src_linesize;
327  }
328 }
329 
331 {
332  AVFilterContext *ctx = inlink->dst;
334  AVFilterLink *outlink = ctx->outputs[0];
335  int p, direct = 0;
336  AVFrame *out;
337 
338  if (edgedetect->mode != MODE_COLORMIX && av_frame_is_writable(in)) {
339  direct = 1;
340  out = in;
341  } else {
342  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
343  if (!out) {
344  av_frame_free(&in);
345  return AVERROR(ENOMEM);
346  }
347  av_frame_copy_props(out, in);
348  }
349 
350  for (p = 0; p < edgedetect->nb_planes; p++) {
351  struct plane_info *plane = &edgedetect->planes[p];
352  uint8_t *tmpbuf = plane->tmpbuf;
353  uint16_t *gradients = plane->gradients;
354  int8_t *directions = plane->directions;
355  const int width = plane->width;
356  const int height = plane->height;
357 
358  if (!((1 << p) & edgedetect->filter_planes)) {
359  if (!direct)
360  av_image_copy_plane(out->data[p], out->linesize[p],
361  in->data[p], in->linesize[p],
362  width, height);
363  continue;
364  }
365 
366  /* gaussian filter to reduce noise */
367  gaussian_blur(ctx, width, height,
368  tmpbuf, width,
369  in->data[p], in->linesize[p]);
370 
371  /* compute the 16-bits gradients and directions for the next step */
372  sobel(width, height,
373  gradients, width,
374  directions,width,
375  tmpbuf, width);
376 
377  /* non_maximum_suppression() will actually keep & clip what's necessary and
378  * ignore the rest, so we need a clean output buffer */
379  memset(tmpbuf, 0, width * height);
380  non_maximum_suppression(width, height,
381  tmpbuf, width,
382  directions,width,
383  gradients, width);
384 
385  /* keep high values, or low values surrounded by high values */
386  double_threshold(edgedetect->low_u8, edgedetect->high_u8,
387  width, height,
388  out->data[p], out->linesize[p],
389  tmpbuf, width);
390 
391  if (edgedetect->mode == MODE_COLORMIX) {
392  color_mix(width, height,
393  out->data[p], out->linesize[p],
394  in->data[p], in->linesize[p]);
395  }
396  }
397 
398  if (!direct)
399  av_frame_free(&in);
400  return ff_filter_frame(outlink, out);
401 }
402 
404 {
405  int p;
407 
408  for (p = 0; p < edgedetect->nb_planes; p++) {
409  struct plane_info *plane = &edgedetect->planes[p];
410  av_freep(&plane->tmpbuf);
411  av_freep(&plane->gradients);
412  av_freep(&plane->directions);
413  }
414 }
415 
416 static const AVFilterPad edgedetect_inputs[] = {
417  {
418  .name = "default",
419  .type = AVMEDIA_TYPE_VIDEO,
420  .config_props = config_props,
421  .filter_frame = filter_frame,
422  },
423  { NULL }
424 };
425 
426 static const AVFilterPad edgedetect_outputs[] = {
427  {
428  .name = "default",
429  .type = AVMEDIA_TYPE_VIDEO,
430  },
431  { NULL }
432 };
433 
435  .name = "edgedetect",
436  .description = NULL_IF_CONFIG_SMALL("Detect and draw edge."),
437  .priv_size = sizeof(EdgeDetectContext),
438  .init = init,
439  .uninit = uninit,
441  .inputs = edgedetect_inputs,
442  .outputs = edgedetect_outputs,
443  .priv_class = &edgedetect_class,
445 };
int plane
Definition: avisynth_c.h:384
static const AVFilterPad edgedetect_outputs[]
#define NULL
Definition: coverity.c:32
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2522
static av_cold void uninit(AVFilterContext *ctx)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:71
misc image utilities
Main libavfilter public API header.
static void sobel(int w, int h, uint16_t *dst, int dst_linesize, int8_t *dir, int dir_linesize, const uint8_t *src, int src_linesize)
const char * desc
Definition: nvenc.c:68
planar GBR 4:4:4 24bpp
Definition: pixfmt.h:168
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:99
#define src
Definition: vp8dsp.c:254
uint8_t log2_chroma_w
Amount to shift the luma width right to find the chroma width.
Definition: pixdesc.h:92
#define PLANE_B
Definition: vf_edgedetect.c:38
void * av_calloc(size_t nmemb, size_t size)
Non-inlined equivalent of av_mallocz_array().
Definition: mem.c:244
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
static void double_threshold(int low, int high, int w, int h, uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize)
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:125
const char * name
Pad name.
Definition: internal.h:60
#define PLANE_V
Definition: vf_edgedetect.c:41
#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:1093
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
AVOptions.
This document is a tutorial initiation for writing simple filters in libavfilter libavfilter is which means that it is highly recommended that you submit your filters to the FFmpeg development mailing list and make sure that they are applied your filters are likely to have a very short lifetime due to more or less regular internal API and a limited and testing changes the pixels in whatever fashion you and outputs the modified frame The most simple way of doing this is to take a similar filter We ll pick edgedetect
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
static int query_formats(AVFilterContext *ctx)
Definition: vf_edgedetect.c:98
char * directions
Definition: vf_edgedetect.c:54
#define PLANE_G
Definition: vf_edgedetect.c:37
AVFILTER_DEFINE_CLASS(edgedetect)
A filter pad used for either input or output.
Definition: internal.h:54
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
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:569
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:101
static const AVOption edgedetect_options[]
Definition: vf_edgedetect.c:70
#define FLAGS
Definition: vf_edgedetect.c:69
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define PLANE_R
Definition: vf_edgedetect.c:36
#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
uint16_t * gradients
Definition: vf_edgedetect.c:53
simple assert() macros that are a bit more flexible than ISO C assert().
static int config_props(AVFilterLink *inlink)
AVFilter ff_vf_edgedetect
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:70
static const struct @321 planes[]
static void gaussian_blur(AVFilterContext *ctx, int w, int h, uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize)
uint8_t w
Definition: llviddspenc.c:38
AVFormatContext * ctx
Definition: movenc.c:48
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
static int get_rounded_direction(int gx, int gy)
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
static const AVFilterPad edgedetect_inputs[]
static av_cold int init(AVFilterContext *ctx)
Definition: vf_edgedetect.c:89
FilterMode
Definition: vp9.h:64
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:594
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
struct plane_info planes[3]
Definition: vf_edgedetect.c:60
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
#define OFFSET(x)
Definition: vf_edgedetect.c:68
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
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
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
#define COPY_MAXIMA(ay, ax, by, bx)
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
static void non_maximum_suppression(int w, int h, uint8_t *dst, int dst_linesize, const int8_t *dir, int dir_linesize, const uint16_t *src, int src_linesize)
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
#define PLANE_Y
Definition: vf_edgedetect.c:39
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
Y , 8bpp.
Definition: pixfmt.h:74
#define PLANE_U
Definition: vf_edgedetect.c:40
uint8_t * tmpbuf
Definition: vf_edgedetect.c:52
static void color_mix(int w, int h, uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize)
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
#define av_freep(p)
void av_image_copy_plane(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height)
Copy image plane from src to dst.
Definition: imgutils.c:338
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
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83
static void hsub(htype *dst, const htype *src, int bins)
Definition: vf_median.c:74
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:654
#define AV_CEIL_RSHIFT(a, b)
Definition: common.h:58