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  memcpy(dst, src, w); dst += dst_linesize; src += src_linesize;
154  for (j = 2; j < h - 2; j++) {
155  dst[0] = src[0];
156  dst[1] = src[1];
157  for (i = 2; i < w - 2; i++) {
158  /* Gaussian mask of size 5x5 with sigma = 1.4 */
159  dst[i] = ((src[-2*src_linesize + i-2] + src[2*src_linesize + i-2]) * 2
160  + (src[-2*src_linesize + i-1] + src[2*src_linesize + i-1]) * 4
161  + (src[-2*src_linesize + i ] + src[2*src_linesize + i ]) * 5
162  + (src[-2*src_linesize + i+1] + src[2*src_linesize + i+1]) * 4
163  + (src[-2*src_linesize + i+2] + src[2*src_linesize + i+2]) * 2
164 
165  + (src[ -src_linesize + i-2] + src[ src_linesize + i-2]) * 4
166  + (src[ -src_linesize + i-1] + src[ src_linesize + i-1]) * 9
167  + (src[ -src_linesize + i ] + src[ src_linesize + i ]) * 12
168  + (src[ -src_linesize + i+1] + src[ src_linesize + i+1]) * 9
169  + (src[ -src_linesize + i+2] + src[ src_linesize + i+2]) * 4
170 
171  + src[i-2] * 5
172  + src[i-1] * 12
173  + src[i ] * 15
174  + src[i+1] * 12
175  + src[i+2] * 5) / 159;
176  }
177  dst[i ] = src[i ];
178  dst[i + 1] = src[i + 1];
179 
180  dst += dst_linesize;
181  src += src_linesize;
182  }
183  memcpy(dst, src, w); dst += dst_linesize; src += src_linesize;
184  memcpy(dst, src, w);
185 }
186 
187 enum {
192 };
193 
194 static int get_rounded_direction(int gx, int gy)
195 {
196  /* reference angles:
197  * tan( pi/8) = sqrt(2)-1
198  * tan(3pi/8) = sqrt(2)+1
199  * Gy/Gx is the tangent of the angle (theta), so Gy/Gx is compared against
200  * <ref-angle>, or more simply Gy against <ref-angle>*Gx
201  *
202  * Gx and Gy bounds = [-1020;1020], using 16-bit arithmetic:
203  * round((sqrt(2)-1) * (1<<16)) = 27146
204  * round((sqrt(2)+1) * (1<<16)) = 158218
205  */
206  if (gx) {
207  int tanpi8gx, tan3pi8gx;
208 
209  if (gx < 0)
210  gx = -gx, gy = -gy;
211  gy <<= 16;
212  tanpi8gx = 27146 * gx;
213  tan3pi8gx = 158218 * gx;
214  if (gy > -tan3pi8gx && gy < -tanpi8gx) return DIRECTION_45UP;
215  if (gy > -tanpi8gx && gy < tanpi8gx) return DIRECTION_HORIZONTAL;
216  if (gy > tanpi8gx && gy < tan3pi8gx) return DIRECTION_45DOWN;
217  }
218  return DIRECTION_VERTICAL;
219 }
220 
221 static void sobel(int w, int h,
222  uint16_t *dst, int dst_linesize,
223  int8_t *dir, int dir_linesize,
224  const uint8_t *src, int src_linesize)
225 {
226  int i, j;
227 
228  for (j = 1; j < h - 1; j++) {
229  dst += dst_linesize;
230  dir += dir_linesize;
231  src += src_linesize;
232  for (i = 1; i < w - 1; i++) {
233  const int gx =
234  -1*src[-src_linesize + i-1] + 1*src[-src_linesize + i+1]
235  -2*src[ i-1] + 2*src[ i+1]
236  -1*src[ src_linesize + i-1] + 1*src[ src_linesize + i+1];
237  const int gy =
238  -1*src[-src_linesize + i-1] + 1*src[ src_linesize + i-1]
239  -2*src[-src_linesize + i ] + 2*src[ src_linesize + i ]
240  -1*src[-src_linesize + i+1] + 1*src[ src_linesize + i+1];
241 
242  dst[i] = FFABS(gx) + FFABS(gy);
243  dir[i] = get_rounded_direction(gx, gy);
244  }
245  }
246 }
247 
248 static void non_maximum_suppression(int w, int h,
249  uint8_t *dst, int dst_linesize,
250  const int8_t *dir, int dir_linesize,
251  const uint16_t *src, int src_linesize)
252 {
253  int i, j;
254 
255 #define COPY_MAXIMA(ay, ax, by, bx) do { \
256  if (src[i] > src[(ay)*src_linesize + i+(ax)] && \
257  src[i] > src[(by)*src_linesize + i+(bx)]) \
258  dst[i] = av_clip_uint8(src[i]); \
259 } while (0)
260 
261  for (j = 1; j < h - 1; j++) {
262  dst += dst_linesize;
263  dir += dir_linesize;
264  src += src_linesize;
265  for (i = 1; i < w - 1; i++) {
266  switch (dir[i]) {
267  case DIRECTION_45UP: COPY_MAXIMA( 1, -1, -1, 1); break;
268  case DIRECTION_45DOWN: COPY_MAXIMA(-1, -1, 1, 1); break;
269  case DIRECTION_HORIZONTAL: COPY_MAXIMA( 0, -1, 0, 1); break;
270  case DIRECTION_VERTICAL: COPY_MAXIMA(-1, 0, 1, 0); break;
271  }
272  }
273  }
274 }
275 
276 static void double_threshold(int low, int high, int w, int h,
277  uint8_t *dst, int dst_linesize,
278  const uint8_t *src, int src_linesize)
279 {
280  int i, j;
281 
282  for (j = 0; j < h; j++) {
283  for (i = 0; i < w; i++) {
284  if (src[i] > high) {
285  dst[i] = src[i];
286  continue;
287  }
288 
289  if ((!i || i == w - 1 || !j || j == h - 1) &&
290  src[i] > low &&
291  (src[-src_linesize + i-1] > high ||
292  src[-src_linesize + i ] > high ||
293  src[-src_linesize + i+1] > high ||
294  src[ i-1] > high ||
295  src[ i+1] > high ||
296  src[ src_linesize + i-1] > high ||
297  src[ src_linesize + i ] > high ||
298  src[ src_linesize + i+1] > high))
299  dst[i] = src[i];
300  else
301  dst[i] = 0;
302  }
303  dst += dst_linesize;
304  src += src_linesize;
305  }
306 }
307 
308 static void color_mix(int w, int h,
309  uint8_t *dst, int dst_linesize,
310  const uint8_t *src, int src_linesize)
311 {
312  int i, j;
313 
314  for (j = 0; j < h; j++) {
315  for (i = 0; i < w; i++)
316  dst[i] = (dst[i] + src[i]) >> 1;
317  dst += dst_linesize;
318  src += src_linesize;
319  }
320 }
321 
323 {
324  AVFilterContext *ctx = inlink->dst;
326  AVFilterLink *outlink = ctx->outputs[0];
327  int p, direct = 0;
328  AVFrame *out;
329 
330  if (edgedetect->mode != MODE_COLORMIX && av_frame_is_writable(in)) {
331  direct = 1;
332  out = in;
333  } else {
334  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
335  if (!out) {
336  av_frame_free(&in);
337  return AVERROR(ENOMEM);
338  }
339  av_frame_copy_props(out, in);
340  }
341 
342  for (p = 0; p < edgedetect->nb_planes; p++) {
343  struct plane_info *plane = &edgedetect->planes[p];
344  uint8_t *tmpbuf = plane->tmpbuf;
345  uint16_t *gradients = plane->gradients;
346  int8_t *directions = plane->directions;
347  const int width = plane->width;
348  const int height = plane->height;
349 
350  if (!((1 << p) & edgedetect->filter_planes)) {
351  if (!direct)
352  av_image_copy_plane(out->data[p], out->linesize[p],
353  in->data[p], in->linesize[p],
354  width, height);
355  continue;
356  }
357 
358  /* gaussian filter to reduce noise */
359  gaussian_blur(ctx, width, height,
360  tmpbuf, width,
361  in->data[p], in->linesize[p]);
362 
363  /* compute the 16-bits gradients and directions for the next step */
364  sobel(width, height,
365  gradients, width,
366  directions,width,
367  tmpbuf, width);
368 
369  /* non_maximum_suppression() will actually keep & clip what's necessary and
370  * ignore the rest, so we need a clean output buffer */
371  memset(tmpbuf, 0, width * height);
372  non_maximum_suppression(width, height,
373  tmpbuf, width,
374  directions,width,
375  gradients, width);
376 
377  /* keep high values, or low values surrounded by high values */
378  double_threshold(edgedetect->low_u8, edgedetect->high_u8,
379  width, height,
380  out->data[p], out->linesize[p],
381  tmpbuf, width);
382 
383  if (edgedetect->mode == MODE_COLORMIX) {
384  color_mix(width, height,
385  out->data[p], out->linesize[p],
386  in->data[p], in->linesize[p]);
387  }
388  }
389 
390  if (!direct)
391  av_frame_free(&in);
392  return ff_filter_frame(outlink, out);
393 }
394 
396 {
397  int p;
399 
400  for (p = 0; p < edgedetect->nb_planes; p++) {
401  struct plane_info *plane = &edgedetect->planes[p];
402  av_freep(&plane->tmpbuf);
403  av_freep(&plane->gradients);
404  av_freep(&plane->directions);
405  }
406 }
407 
408 static const AVFilterPad edgedetect_inputs[] = {
409  {
410  .name = "default",
411  .type = AVMEDIA_TYPE_VIDEO,
412  .config_props = config_props,
413  .filter_frame = filter_frame,
414  },
415  { NULL }
416 };
417 
418 static const AVFilterPad edgedetect_outputs[] = {
419  {
420  .name = "default",
421  .type = AVMEDIA_TYPE_VIDEO,
422  },
423  { NULL }
424 };
425 
427  .name = "edgedetect",
428  .description = NULL_IF_CONFIG_SMALL("Detect and draw edge."),
429  .priv_size = sizeof(EdgeDetectContext),
430  .init = init,
431  .uninit = uninit,
433  .inputs = edgedetect_inputs,
434  .outputs = edgedetect_outputs,
435  .priv_class = &edgedetect_class,
437 };
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:1080
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:568
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 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 struct @316 planes[]
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
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