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vf_deshake.c
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1 /*
2  * Copyright (C) 2010 Georg Martius <georg.martius@web.de>
3  * Copyright (C) 2010 Daniel G. Taylor <dan@programmer-art.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * fast deshake / depan video filter
25  *
26  * SAD block-matching motion compensation to fix small changes in
27  * horizontal and/or vertical shift. This filter helps remove camera shake
28  * from hand-holding a camera, bumping a tripod, moving on a vehicle, etc.
29  *
30  * Algorithm:
31  * - For each frame with one previous reference frame
32  * - For each block in the frame
33  * - If contrast > threshold then find likely motion vector
34  * - For all found motion vectors
35  * - Find most common, store as global motion vector
36  * - Find most likely rotation angle
37  * - Transform image along global motion
38  *
39  * TODO:
40  * - Fill frame edges based on previous/next reference frames
41  * - Fill frame edges by stretching image near the edges?
42  * - Can this be done quickly and look decent?
43  *
44  * Dark Shikari links to http://wiki.videolan.org/SoC_x264_2010#GPU_Motion_Estimation_2
45  * for an algorithm similar to what could be used here to get the gmv
46  * It requires only a couple diamond searches + fast downscaling
47  *
48  * Special thanks to Jason Kotenko for his help with the algorithm and my
49  * inability to see simple errors in C code.
50  */
51 
52 #include "avfilter.h"
53 #include "formats.h"
54 #include "internal.h"
55 #include "video.h"
56 #include "libavutil/common.h"
57 #include "libavutil/mem.h"
58 #include "libavutil/opt.h"
59 #include "libavutil/pixdesc.h"
60 
61 #include "deshake.h"
62 #include "deshake_opencl.h"
63 
64 #define CHROMA_WIDTH(link) (-((-(link)->w) >> av_pix_fmt_desc_get((link)->format)->log2_chroma_w))
65 #define CHROMA_HEIGHT(link) (-((-(link)->h) >> av_pix_fmt_desc_get((link)->format)->log2_chroma_h))
66 
67 #define OFFSET(x) offsetof(DeshakeContext, x)
68 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
69 
70 static const AVOption deshake_options[] = {
71  { "x", "set x for the rectangular search area", OFFSET(cx), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
72  { "y", "set y for the rectangular search area", OFFSET(cy), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
73  { "w", "set width for the rectangular search area", OFFSET(cw), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
74  { "h", "set height for the rectangular search area", OFFSET(ch), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, .flags = FLAGS },
75  { "rx", "set x for the rectangular search area", OFFSET(rx), AV_OPT_TYPE_INT, {.i64=16}, 0, MAX_R, .flags = FLAGS },
76  { "ry", "set y for the rectangular search area", OFFSET(ry), AV_OPT_TYPE_INT, {.i64=16}, 0, MAX_R, .flags = FLAGS },
77  { "edge", "set edge mode", OFFSET(edge), AV_OPT_TYPE_INT, {.i64=FILL_MIRROR}, FILL_BLANK, FILL_COUNT-1, FLAGS, "edge"},
78  { "blank", "fill zeroes at blank locations", 0, AV_OPT_TYPE_CONST, {.i64=FILL_BLANK}, INT_MIN, INT_MAX, FLAGS, "edge" },
79  { "original", "original image at blank locations", 0, AV_OPT_TYPE_CONST, {.i64=FILL_ORIGINAL}, INT_MIN, INT_MAX, FLAGS, "edge" },
80  { "clamp", "extruded edge value at blank locations", 0, AV_OPT_TYPE_CONST, {.i64=FILL_CLAMP}, INT_MIN, INT_MAX, FLAGS, "edge" },
81  { "mirror", "mirrored edge at blank locations", 0, AV_OPT_TYPE_CONST, {.i64=FILL_MIRROR}, INT_MIN, INT_MAX, FLAGS, "edge" },
82  { "blocksize", "set motion search blocksize", OFFSET(blocksize), AV_OPT_TYPE_INT, {.i64=8}, 4, 128, .flags = FLAGS },
83  { "contrast", "set contrast threshold for blocks", OFFSET(contrast), AV_OPT_TYPE_INT, {.i64=125}, 1, 255, .flags = FLAGS },
84  { "search", "set search strategy", OFFSET(search), AV_OPT_TYPE_INT, {.i64=EXHAUSTIVE}, EXHAUSTIVE, SEARCH_COUNT-1, FLAGS, "smode" },
85  { "exhaustive", "exhaustive search", 0, AV_OPT_TYPE_CONST, {.i64=EXHAUSTIVE}, INT_MIN, INT_MAX, FLAGS, "smode" },
86  { "less", "less exhaustive search", 0, AV_OPT_TYPE_CONST, {.i64=SMART_EXHAUSTIVE}, INT_MIN, INT_MAX, FLAGS, "smode" },
87  { "filename", "set motion search detailed log file name", OFFSET(filename), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
88  { "opencl", "use OpenCL filtering capabilities", OFFSET(opencl), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, .flags = FLAGS },
89  { NULL }
90 };
91 
92 AVFILTER_DEFINE_CLASS(deshake);
93 
94 static int cmp(const double *a, const double *b)
95 {
96  return *a < *b ? -1 : ( *a > *b ? 1 : 0 );
97 }
98 
99 /**
100  * Cleaned mean (cuts off 20% of values to remove outliers and then averages)
101  */
102 static double clean_mean(double *values, int count)
103 {
104  double mean = 0;
105  int cut = count / 5;
106  int x;
107 
108  qsort(values, count, sizeof(double), (void*)cmp);
109 
110  for (x = cut; x < count - cut; x++) {
111  mean += values[x];
112  }
113 
114  return mean / (count - cut * 2);
115 }
116 
117 /**
118  * Find the most likely shift in motion between two frames for a given
119  * macroblock. Test each block against several shifts given by the rx
120  * and ry attributes. Searches using a simple matrix of those shifts and
121  * chooses the most likely shift by the smallest difference in blocks.
122  */
123 static void find_block_motion(DeshakeContext *deshake, uint8_t *src1,
124  uint8_t *src2, int cx, int cy, int stride,
126 {
127  int x, y;
128  int diff;
129  int smallest = INT_MAX;
130  int tmp, tmp2;
131 
132  #define CMP(i, j) deshake->sad(src1 + cy * stride + cx, stride,\
133  src2 + (j) * stride + (i), stride)
134 
135  if (deshake->search == EXHAUSTIVE) {
136  // Compare every possible position - this is sloooow!
137  for (y = -deshake->ry; y <= deshake->ry; y++) {
138  for (x = -deshake->rx; x <= deshake->rx; x++) {
139  diff = CMP(cx - x, cy - y);
140  if (diff < smallest) {
141  smallest = diff;
142  mv->x = x;
143  mv->y = y;
144  }
145  }
146  }
147  } else if (deshake->search == SMART_EXHAUSTIVE) {
148  // Compare every other possible position and find the best match
149  for (y = -deshake->ry + 1; y < deshake->ry; y += 2) {
150  for (x = -deshake->rx + 1; x < deshake->rx; x += 2) {
151  diff = CMP(cx - x, cy - y);
152  if (diff < smallest) {
153  smallest = diff;
154  mv->x = x;
155  mv->y = y;
156  }
157  }
158  }
159 
160  // Hone in on the specific best match around the match we found above
161  tmp = mv->x;
162  tmp2 = mv->y;
163 
164  for (y = tmp2 - 1; y <= tmp2 + 1; y++) {
165  for (x = tmp - 1; x <= tmp + 1; x++) {
166  if (x == tmp && y == tmp2)
167  continue;
168 
169  diff = CMP(cx - x, cy - y);
170  if (diff < smallest) {
171  smallest = diff;
172  mv->x = x;
173  mv->y = y;
174  }
175  }
176  }
177  }
178 
179  if (smallest > 512) {
180  mv->x = -1;
181  mv->y = -1;
182  }
183  emms_c();
184  //av_log(NULL, AV_LOG_ERROR, "%d\n", smallest);
185  //av_log(NULL, AV_LOG_ERROR, "Final: (%d, %d) = %d x %d\n", cx, cy, mv->x, mv->y);
186 }
187 
188 /**
189  * Find the contrast of a given block. When searching for global motion we
190  * really only care about the high contrast blocks, so using this method we
191  * can actually skip blocks we don't care much about.
192  */
193 static int block_contrast(uint8_t *src, int x, int y, int stride, int blocksize)
194 {
195  int highest = 0;
196  int lowest = 255;
197  int i, j, pos;
198 
199  for (i = 0; i <= blocksize * 2; i++) {
200  // We use a width of 16 here to match the sad function
201  for (j = 0; j <= 15; j++) {
202  pos = (y - i) * stride + (x - j);
203  if (src[pos] < lowest)
204  lowest = src[pos];
205  else if (src[pos] > highest) {
206  highest = src[pos];
207  }
208  }
209  }
210 
211  return highest - lowest;
212 }
213 
214 /**
215  * Find the rotation for a given block.
216  */
217 static double block_angle(int x, int y, int cx, int cy, IntMotionVector *shift)
218 {
219  double a1, a2, diff;
220 
221  a1 = atan2(y - cy, x - cx);
222  a2 = atan2(y - cy + shift->y, x - cx + shift->x);
223 
224  diff = a2 - a1;
225 
226  return (diff > M_PI) ? diff - 2 * M_PI :
227  (diff < -M_PI) ? diff + 2 * M_PI :
228  diff;
229 }
230 
231 /**
232  * Find the estimated global motion for a scene given the most likely shift
233  * for each block in the frame. The global motion is estimated to be the
234  * same as the motion from most blocks in the frame, so if most blocks
235  * move one pixel to the right and two pixels down, this would yield a
236  * motion vector (1, -2).
237  */
238 static void find_motion(DeshakeContext *deshake, uint8_t *src1, uint8_t *src2,
239  int width, int height, int stride, Transform *t)
240 {
241  int x, y;
242  IntMotionVector mv = {0, 0};
243  int count_max_value = 0;
244  int contrast;
245 
246  int pos;
247  int center_x = 0, center_y = 0;
248  double p_x, p_y;
249 
250  av_fast_malloc(&deshake->angles, &deshake->angles_size, width * height / (16 * deshake->blocksize) * sizeof(*deshake->angles));
251 
252  // Reset counts to zero
253  for (x = 0; x < deshake->rx * 2 + 1; x++) {
254  for (y = 0; y < deshake->ry * 2 + 1; y++) {
255  deshake->counts[x][y] = 0;
256  }
257  }
258 
259  pos = 0;
260  // Find motion for every block and store the motion vector in the counts
261  for (y = deshake->ry; y < height - deshake->ry - (deshake->blocksize * 2); y += deshake->blocksize * 2) {
262  // We use a width of 16 here to match the sad function
263  for (x = deshake->rx; x < width - deshake->rx - 16; x += 16) {
264  // If the contrast is too low, just skip this block as it probably
265  // won't be very useful to us.
266  contrast = block_contrast(src2, x, y, stride, deshake->blocksize);
267  if (contrast > deshake->contrast) {
268  //av_log(NULL, AV_LOG_ERROR, "%d\n", contrast);
269  find_block_motion(deshake, src1, src2, x, y, stride, &mv);
270  if (mv.x != -1 && mv.y != -1) {
271  deshake->counts[mv.x + deshake->rx][mv.y + deshake->ry] += 1;
272  if (x > deshake->rx && y > deshake->ry)
273  deshake->angles[pos++] = block_angle(x, y, 0, 0, &mv);
274 
275  center_x += mv.x;
276  center_y += mv.y;
277  }
278  }
279  }
280  }
281 
282  if (pos) {
283  center_x /= pos;
284  center_y /= pos;
285  t->angle = clean_mean(deshake->angles, pos);
286  if (t->angle < 0.001)
287  t->angle = 0;
288  } else {
289  t->angle = 0;
290  }
291 
292  // Find the most common motion vector in the frame and use it as the gmv
293  for (y = deshake->ry * 2; y >= 0; y--) {
294  for (x = 0; x < deshake->rx * 2 + 1; x++) {
295  //av_log(NULL, AV_LOG_ERROR, "%5d ", deshake->counts[x][y]);
296  if (deshake->counts[x][y] > count_max_value) {
297  t->vec.x = x - deshake->rx;
298  t->vec.y = y - deshake->ry;
299  count_max_value = deshake->counts[x][y];
300  }
301  }
302  //av_log(NULL, AV_LOG_ERROR, "\n");
303  }
304 
305  p_x = (center_x - width / 2.0);
306  p_y = (center_y - height / 2.0);
307  t->vec.x += (cos(t->angle)-1)*p_x - sin(t->angle)*p_y;
308  t->vec.y += sin(t->angle)*p_x + (cos(t->angle)-1)*p_y;
309 
310  // Clamp max shift & rotation?
311  t->vec.x = av_clipf(t->vec.x, -deshake->rx * 2, deshake->rx * 2);
312  t->vec.y = av_clipf(t->vec.y, -deshake->ry * 2, deshake->ry * 2);
313  t->angle = av_clipf(t->angle, -0.1, 0.1);
314 
315  //av_log(NULL, AV_LOG_ERROR, "%d x %d\n", avg->x, avg->y);
316 }
317 
319  int width, int height, int cw, int ch,
320  const float *matrix_y, const float *matrix_uv,
322  enum FillMethod fill, AVFrame *in, AVFrame *out)
323 {
324  int i = 0, ret = 0;
325  const float *matrixs[3];
326  int plane_w[3], plane_h[3];
327  matrixs[0] = matrix_y;
328  matrixs[1] = matrixs[2] = matrix_uv;
329  plane_w[0] = width;
330  plane_w[1] = plane_w[2] = cw;
331  plane_h[0] = height;
332  plane_h[1] = plane_h[2] = ch;
333 
334  for (i = 0; i < 3; i++) {
335  // Transform the luma and chroma planes
336  ret = avfilter_transform(in->data[i], out->data[i], in->linesize[i], out->linesize[i],
337  plane_w[i], plane_h[i], matrixs[i], interpolate, fill);
338  if (ret < 0)
339  return ret;
340  }
341  return ret;
342 }
343 
344 static av_cold int init(AVFilterContext *ctx)
345 {
346  int ret;
347  DeshakeContext *deshake = ctx->priv;
348 
349  deshake->sad = av_pixelutils_get_sad_fn(4, 4, 1, deshake); // 16x16, 2nd source unaligned
350  if (!deshake->sad)
351  return AVERROR(EINVAL);
352 
353  deshake->refcount = 20; // XXX: add to options?
354  deshake->blocksize /= 2;
355  deshake->blocksize = av_clip(deshake->blocksize, 4, 128);
356 
357  if (deshake->rx % 16) {
358  av_log(ctx, AV_LOG_ERROR, "rx must be a multiple of 16\n");
359  return AVERROR_PATCHWELCOME;
360  }
361 
362  if (deshake->filename)
363  deshake->fp = fopen(deshake->filename, "w");
364  if (deshake->fp)
365  fwrite("Ori x, Avg x, Fin x, Ori y, Avg y, Fin y, Ori angle, Avg angle, Fin angle, Ori zoom, Avg zoom, Fin zoom\n", sizeof(char), 104, deshake->fp);
366 
367  // Quadword align left edge of box for MMX code, adjust width if necessary
368  // to keep right margin
369  if (deshake->cx > 0) {
370  deshake->cw += deshake->cx - (deshake->cx & ~15);
371  deshake->cx &= ~15;
372  }
373  deshake->transform = deshake_transform_c;
374  if (!CONFIG_OPENCL && deshake->opencl) {
375  av_log(ctx, AV_LOG_ERROR, "OpenCL support was not enabled in this build, cannot be selected\n");
376  return AVERROR(EINVAL);
377  }
378 
379  if (CONFIG_OPENCL && deshake->opencl) {
380  deshake->transform = ff_opencl_transform;
381  ret = ff_opencl_deshake_init(ctx);
382  if (ret < 0)
383  return ret;
384  }
385  av_log(ctx, AV_LOG_VERBOSE, "cx: %d, cy: %d, cw: %d, ch: %d, rx: %d, ry: %d, edge: %d blocksize: %d contrast: %d search: %d\n",
386  deshake->cx, deshake->cy, deshake->cw, deshake->ch,
387  deshake->rx, deshake->ry, deshake->edge, deshake->blocksize * 2, deshake->contrast, deshake->search);
388 
389  return 0;
390 }
391 
393 {
394  static const enum AVPixelFormat pix_fmts[] = {
398  };
399  AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
400  if (!fmts_list)
401  return AVERROR(ENOMEM);
402  return ff_set_common_formats(ctx, fmts_list);
403 }
404 
405 static int config_props(AVFilterLink *link)
406 {
407  DeshakeContext *deshake = link->dst->priv;
408 
409  deshake->ref = NULL;
410  deshake->last.vec.x = 0;
411  deshake->last.vec.y = 0;
412  deshake->last.angle = 0;
413  deshake->last.zoom = 0;
414 
415  return 0;
416 }
417 
418 static av_cold void uninit(AVFilterContext *ctx)
419 {
420  DeshakeContext *deshake = ctx->priv;
421  if (CONFIG_OPENCL && deshake->opencl) {
423  }
424  av_frame_free(&deshake->ref);
425  av_freep(&deshake->angles);
426  deshake->angles_size = 0;
427  if (deshake->fp)
428  fclose(deshake->fp);
429 }
430 
431 static int filter_frame(AVFilterLink *link, AVFrame *in)
432 {
433  DeshakeContext *deshake = link->dst->priv;
434  AVFilterLink *outlink = link->dst->outputs[0];
435  AVFrame *out;
436  Transform t = {{0},0}, orig = {{0},0};
437  float matrix_y[9], matrix_uv[9];
438  float alpha = 2.0 / deshake->refcount;
439  char tmp[256];
440  int ret = 0;
441 
442  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
443  if (!out) {
444  av_frame_free(&in);
445  return AVERROR(ENOMEM);
446  }
447  av_frame_copy_props(out, in);
448 
449  if (CONFIG_OPENCL && deshake->opencl) {
450  ret = ff_opencl_deshake_process_inout_buf(link->dst,in, out);
451  if (ret < 0)
452  return ret;
453  }
454 
455  if (deshake->cx < 0 || deshake->cy < 0 || deshake->cw < 0 || deshake->ch < 0) {
456  // Find the most likely global motion for the current frame
457  find_motion(deshake, (deshake->ref == NULL) ? in->data[0] : deshake->ref->data[0], in->data[0], link->w, link->h, in->linesize[0], &t);
458  } else {
459  uint8_t *src1 = (deshake->ref == NULL) ? in->data[0] : deshake->ref->data[0];
460  uint8_t *src2 = in->data[0];
461 
462  deshake->cx = FFMIN(deshake->cx, link->w);
463  deshake->cy = FFMIN(deshake->cy, link->h);
464 
465  if ((unsigned)deshake->cx + (unsigned)deshake->cw > link->w) deshake->cw = link->w - deshake->cx;
466  if ((unsigned)deshake->cy + (unsigned)deshake->ch > link->h) deshake->ch = link->h - deshake->cy;
467 
468  // Quadword align right margin
469  deshake->cw &= ~15;
470 
471  src1 += deshake->cy * in->linesize[0] + deshake->cx;
472  src2 += deshake->cy * in->linesize[0] + deshake->cx;
473 
474  find_motion(deshake, src1, src2, deshake->cw, deshake->ch, in->linesize[0], &t);
475  }
476 
477 
478  // Copy transform so we can output it later to compare to the smoothed value
479  orig.vec.x = t.vec.x;
480  orig.vec.y = t.vec.y;
481  orig.angle = t.angle;
482  orig.zoom = t.zoom;
483 
484  // Generate a one-sided moving exponential average
485  deshake->avg.vec.x = alpha * t.vec.x + (1.0 - alpha) * deshake->avg.vec.x;
486  deshake->avg.vec.y = alpha * t.vec.y + (1.0 - alpha) * deshake->avg.vec.y;
487  deshake->avg.angle = alpha * t.angle + (1.0 - alpha) * deshake->avg.angle;
488  deshake->avg.zoom = alpha * t.zoom + (1.0 - alpha) * deshake->avg.zoom;
489 
490  // Remove the average from the current motion to detect the motion that
491  // is not on purpose, just as jitter from bumping the camera
492  t.vec.x -= deshake->avg.vec.x;
493  t.vec.y -= deshake->avg.vec.y;
494  t.angle -= deshake->avg.angle;
495  t.zoom -= deshake->avg.zoom;
496 
497  // Invert the motion to undo it
498  t.vec.x *= -1;
499  t.vec.y *= -1;
500  t.angle *= -1;
501 
502  // Write statistics to file
503  if (deshake->fp) {
504  snprintf(tmp, 256, "%f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f\n", orig.vec.x, deshake->avg.vec.x, t.vec.x, orig.vec.y, deshake->avg.vec.y, t.vec.y, orig.angle, deshake->avg.angle, t.angle, orig.zoom, deshake->avg.zoom, t.zoom);
505  fwrite(tmp, sizeof(char), strlen(tmp), deshake->fp);
506  }
507 
508  // Turn relative current frame motion into absolute by adding it to the
509  // last absolute motion
510  t.vec.x += deshake->last.vec.x;
511  t.vec.y += deshake->last.vec.y;
512  t.angle += deshake->last.angle;
513  t.zoom += deshake->last.zoom;
514 
515  // Shrink motion by 10% to keep things centered in the camera frame
516  t.vec.x *= 0.9;
517  t.vec.y *= 0.9;
518  t.angle *= 0.9;
519 
520  // Store the last absolute motion information
521  deshake->last.vec.x = t.vec.x;
522  deshake->last.vec.y = t.vec.y;
523  deshake->last.angle = t.angle;
524  deshake->last.zoom = t.zoom;
525 
526  // Generate a luma transformation matrix
527  avfilter_get_matrix(t.vec.x, t.vec.y, t.angle, 1.0 + t.zoom / 100.0, matrix_y);
528  // Generate a chroma transformation matrix
529  avfilter_get_matrix(t.vec.x / (link->w / CHROMA_WIDTH(link)), t.vec.y / (link->h / CHROMA_HEIGHT(link)), t.angle, 1.0 + t.zoom / 100.0, matrix_uv);
530  // Transform the luma and chroma planes
531  ret = deshake->transform(link->dst, link->w, link->h, CHROMA_WIDTH(link), CHROMA_HEIGHT(link),
532  matrix_y, matrix_uv, INTERPOLATE_BILINEAR, deshake->edge, in, out);
533 
534  // Cleanup the old reference frame
535  av_frame_free(&deshake->ref);
536 
537  if (ret < 0)
538  return ret;
539 
540  // Store the current frame as the reference frame for calculating the
541  // motion of the next frame
542  deshake->ref = in;
543 
544  return ff_filter_frame(outlink, out);
545 }
546 
547 static const AVFilterPad deshake_inputs[] = {
548  {
549  .name = "default",
550  .type = AVMEDIA_TYPE_VIDEO,
551  .filter_frame = filter_frame,
552  .config_props = config_props,
553  },
554  { NULL }
555 };
556 
557 static const AVFilterPad deshake_outputs[] = {
558  {
559  .name = "default",
560  .type = AVMEDIA_TYPE_VIDEO,
561  },
562  { NULL }
563 };
564 
566  .name = "deshake",
567  .description = NULL_IF_CONFIG_SMALL("Stabilize shaky video."),
568  .priv_size = sizeof(DeshakeContext),
569  .init = init,
570  .uninit = uninit,
572  .inputs = deshake_inputs,
573  .outputs = deshake_outputs,
574  .priv_class = &deshake_class,
575 };