FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/vf_perspective.c
Date: 2024-09-07 18:49:03
Exec Total Coverage
Lines: 0 258 0.0%
Functions: 0 8 0.0%
Branches: 0 96 0.0%

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1 /*
2 * Copyright (c) 2002 Michael Niedermayer <michaelni@gmx.at>
3 * Copyright (c) 2013 Paul B Mahol
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 General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 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
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * 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 #include "libavutil/avassert.h"
23 #include "libavutil/eval.h"
24 #include "libavutil/imgutils.h"
25 #include "libavutil/mem.h"
26 #include "libavutil/pixdesc.h"
27 #include "libavutil/opt.h"
28 #include "avfilter.h"
29 #include "filters.h"
30 #include "video.h"
31
32 #define SUB_PIXEL_BITS 8
33 #define SUB_PIXELS (1 << SUB_PIXEL_BITS)
34 #define COEFF_BITS 11
35
36 #define LINEAR 0
37 #define CUBIC 1
38
39 typedef struct PerspectiveContext {
40 const AVClass *class;
41 char *expr_str[4][2];
42 double ref[4][2];
43 int32_t (*pv)[2];
44 int32_t coeff[SUB_PIXELS][4];
45 int interpolation;
46 int linesize[4];
47 int height[4];
48 int hsub, vsub;
49 int nb_planes;
50 int sense;
51 int eval_mode;
52
53 int (*perspective)(AVFilterContext *ctx,
54 void *arg, int job, int nb_jobs);
55 } PerspectiveContext;
56
57 #define OFFSET(x) offsetof(PerspectiveContext, x)
58 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
59
60 enum PERSPECTIVESense {
61 PERSPECTIVE_SENSE_SOURCE = 0, ///< coordinates give locations in source of corners of destination.
62 PERSPECTIVE_SENSE_DESTINATION = 1, ///< coordinates give locations in destination of corners of source.
63 };
64
65 enum EvalMode {
66 EVAL_MODE_INIT,
67 EVAL_MODE_FRAME,
68 EVAL_MODE_NB
69 };
70
71 static const AVOption perspective_options[] = {
72 { "x0", "set top left x coordinate", OFFSET(expr_str[0][0]), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS },
73 { "y0", "set top left y coordinate", OFFSET(expr_str[0][1]), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS },
74 { "x1", "set top right x coordinate", OFFSET(expr_str[1][0]), AV_OPT_TYPE_STRING, {.str="W"}, 0, 0, FLAGS },
75 { "y1", "set top right y coordinate", OFFSET(expr_str[1][1]), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS },
76 { "x2", "set bottom left x coordinate", OFFSET(expr_str[2][0]), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS },
77 { "y2", "set bottom left y coordinate", OFFSET(expr_str[2][1]), AV_OPT_TYPE_STRING, {.str="H"}, 0, 0, FLAGS },
78 { "x3", "set bottom right x coordinate", OFFSET(expr_str[3][0]), AV_OPT_TYPE_STRING, {.str="W"}, 0, 0, FLAGS },
79 { "y3", "set bottom right y coordinate", OFFSET(expr_str[3][1]), AV_OPT_TYPE_STRING, {.str="H"}, 0, 0, FLAGS },
80 { "interpolation", "set interpolation", OFFSET(interpolation), AV_OPT_TYPE_INT, {.i64=LINEAR}, 0, 1, FLAGS, .unit = "interpolation" },
81 { "linear", "", 0, AV_OPT_TYPE_CONST, {.i64=LINEAR}, 0, 0, FLAGS, .unit = "interpolation" },
82 { "cubic", "", 0, AV_OPT_TYPE_CONST, {.i64=CUBIC}, 0, 0, FLAGS, .unit = "interpolation" },
83 { "sense", "specify the sense of the coordinates", OFFSET(sense), AV_OPT_TYPE_INT, {.i64=PERSPECTIVE_SENSE_SOURCE}, 0, 1, FLAGS, .unit = "sense"},
84 { "source", "specify locations in source to send to corners in destination",
85 0, AV_OPT_TYPE_CONST, {.i64=PERSPECTIVE_SENSE_SOURCE}, 0, 0, FLAGS, .unit = "sense"},
86 { "destination", "specify locations in destination to send corners of source",
87 0, AV_OPT_TYPE_CONST, {.i64=PERSPECTIVE_SENSE_DESTINATION}, 0, 0, FLAGS, .unit = "sense"},
88 { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, .unit = "eval" },
89 { "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
90 { "frame", "eval expressions per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
91
92 { NULL }
93 };
94
95 AVFILTER_DEFINE_CLASS(perspective);
96
97 static const enum AVPixelFormat pix_fmts[] = {
98 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
99 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ422P,AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ411P,
100 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
101 AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
102 };
103
104 static inline double get_coeff(double d)
105 {
106 double coeff, A = -0.60;
107
108 d = fabs(d);
109
110 if (d < 1.0)
111 coeff = (1.0 - (A + 3.0) * d * d + (A + 2.0) * d * d * d);
112 else if (d < 2.0)
113 coeff = (-4.0 * A + 8.0 * A * d - 5.0 * A * d * d + A * d * d * d);
114 else
115 coeff = 0.0;
116
117 return coeff;
118 }
119
120 static const char *const var_names[] = { "W", "H", "in", "on", NULL };
121 enum { VAR_W, VAR_H, VAR_IN, VAR_ON, VAR_VARS_NB };
122
123 static int calc_persp_luts(AVFilterContext *ctx, AVFilterLink *inlink)
124 {
125 FilterLink *inl = ff_filter_link(inlink);
126 PerspectiveContext *s = ctx->priv;
127 AVFilterLink *outlink = ctx->outputs[0];
128 FilterLink *outl = ff_filter_link(outlink);
129 double (*ref)[2] = s->ref;
130
131 double values[VAR_VARS_NB] = { [VAR_W] = inlink->w, [VAR_H] = inlink->h,
132 [VAR_IN] = inl->frame_count_out + 1,
133 [VAR_ON] = outl->frame_count_in + 1 };
134 const int h = values[VAR_H];
135 const int w = values[VAR_W];
136 double x0, x1, x2, x3, x4, x5, x6, x7, x8, q;
137 double t0, t1, t2, t3;
138 int x, y, i, j, ret;
139
140 for (i = 0; i < 4; i++) {
141 for (j = 0; j < 2; j++) {
142 if (!s->expr_str[i][j])
143 return AVERROR(EINVAL);
144 ret = av_expr_parse_and_eval(&s->ref[i][j], s->expr_str[i][j],
145 var_names, &values[0],
146 NULL, NULL, NULL, NULL,
147 0, 0, ctx);
148 if (ret < 0)
149 return ret;
150 }
151 }
152
153 switch (s->sense) {
154 case PERSPECTIVE_SENSE_SOURCE:
155 x6 = ((ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
156 (ref[2][1] - ref[3][1]) -
157 ( ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
158 (ref[2][0] - ref[3][0])) * h;
159 x7 = ((ref[0][1] - ref[1][1] - ref[2][1] + ref[3][1]) *
160 (ref[1][0] - ref[3][0]) -
161 ( ref[0][0] - ref[1][0] - ref[2][0] + ref[3][0]) *
162 (ref[1][1] - ref[3][1])) * w;
163 q = ( ref[1][0] - ref[3][0]) * (ref[2][1] - ref[3][1]) -
164 ( ref[2][0] - ref[3][0]) * (ref[1][1] - ref[3][1]);
165
166 x0 = q * (ref[1][0] - ref[0][0]) * h + x6 * ref[1][0];
167 x1 = q * (ref[2][0] - ref[0][0]) * w + x7 * ref[2][0];
168 x2 = q * ref[0][0] * w * h;
169 x3 = q * (ref[1][1] - ref[0][1]) * h + x6 * ref[1][1];
170 x4 = q * (ref[2][1] - ref[0][1]) * w + x7 * ref[2][1];
171 x5 = q * ref[0][1] * w * h;
172 x8 = q * w * h;
173 break;
174 case PERSPECTIVE_SENSE_DESTINATION:
175 t0 = ref[0][0] * (ref[3][1] - ref[1][1]) +
176 ref[1][0] * (ref[0][1] - ref[3][1]) +
177 ref[3][0] * (ref[1][1] - ref[0][1]);
178 t1 = ref[1][0] * (ref[2][1] - ref[3][1]) +
179 ref[2][0] * (ref[3][1] - ref[1][1]) +
180 ref[3][0] * (ref[1][1] - ref[2][1]);
181 t2 = ref[0][0] * (ref[3][1] - ref[2][1]) +
182 ref[2][0] * (ref[0][1] - ref[3][1]) +
183 ref[3][0] * (ref[2][1] - ref[0][1]);
184 t3 = ref[0][0] * (ref[1][1] - ref[2][1]) +
185 ref[1][0] * (ref[2][1] - ref[0][1]) +
186 ref[2][0] * (ref[0][1] - ref[1][1]);
187
188 x0 = t0 * t1 * w * (ref[2][1] - ref[0][1]);
189 x1 = t0 * t1 * w * (ref[0][0] - ref[2][0]);
190 x2 = t0 * t1 * w * (ref[0][1] * ref[2][0] - ref[0][0] * ref[2][1]);
191 x3 = t1 * t2 * h * (ref[1][1] - ref[0][1]);
192 x4 = t1 * t2 * h * (ref[0][0] - ref[1][0]);
193 x5 = t1 * t2 * h * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]);
194 x6 = t1 * t2 * (ref[1][1] - ref[0][1]) +
195 t0 * t3 * (ref[2][1] - ref[3][1]);
196 x7 = t1 * t2 * (ref[0][0] - ref[1][0]) +
197 t0 * t3 * (ref[3][0] - ref[2][0]);
198 x8 = t1 * t2 * (ref[0][1] * ref[1][0] - ref[0][0] * ref[1][1]) +
199 t0 * t3 * (ref[2][0] * ref[3][1] - ref[2][1] * ref[3][0]);
200 break;
201 default:
202 av_assert0(0);
203 }
204
205 for (y = 0; y < h; y++){
206 for (x = 0; x < w; x++){
207 int u, v;
208
209 u = lrint(SUB_PIXELS * (x0 * x + x1 * y + x2) /
210 (x6 * x + x7 * y + x8));
211 v = lrint(SUB_PIXELS * (x3 * x + x4 * y + x5) /
212 (x6 * x + x7 * y + x8));
213
214 s->pv[x + y * w][0] = u;
215 s->pv[x + y * w][1] = v;
216 }
217 }
218
219 return 0;
220 }
221
222 static int config_input(AVFilterLink *inlink)
223 {
224 AVFilterContext *ctx = inlink->dst;
225 PerspectiveContext *s = ctx->priv;
226 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
227 int h = inlink->h;
228 int w = inlink->w;
229 int i, j, ret;
230 s->hsub = desc->log2_chroma_w;
231 s->vsub = desc->log2_chroma_h;
232 s->nb_planes = av_pix_fmt_count_planes(inlink->format);
233 if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
234 return ret;
235
236 s->height[1] = s->height[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
237 s->height[0] = s->height[3] = inlink->h;
238
239 s->pv = av_realloc_f(s->pv, w * h, 2 * sizeof(*s->pv));
240 if (!s->pv)
241 return AVERROR(ENOMEM);
242
243 if (s->eval_mode == EVAL_MODE_INIT) {
244 if ((ret = calc_persp_luts(ctx, inlink)) < 0) {
245 return ret;
246 }
247 }
248
249 for (i = 0; i < SUB_PIXELS; i++){
250 double d = i / (double)SUB_PIXELS;
251 double temp[4];
252 double sum = 0;
253
254 for (j = 0; j < 4; j++)
255 temp[j] = get_coeff(j - d - 1);
256
257 for (j = 0; j < 4; j++)
258 sum += temp[j];
259
260 for (j = 0; j < 4; j++)
261 s->coeff[i][j] = lrint((1 << COEFF_BITS) * temp[j] / sum);
262 }
263
264 return 0;
265 }
266
267 typedef struct ThreadData {
268 uint8_t *dst;
269 int dst_linesize;
270 uint8_t *src;
271 int src_linesize;
272 int w, h;
273 int hsub, vsub;
274 } ThreadData;
275
276 static int resample_cubic(AVFilterContext *ctx, void *arg,
277 int job, int nb_jobs)
278 {
279 PerspectiveContext *s = ctx->priv;
280 ThreadData *td = arg;
281 uint8_t *dst = td->dst;
282 int dst_linesize = td->dst_linesize;
283 uint8_t *src = td->src;
284 int src_linesize = td->src_linesize;
285 int w = td->w;
286 int h = td->h;
287 int hsub = td->hsub;
288 int vsub = td->vsub;
289 int start = (h * job) / nb_jobs;
290 int end = (h * (job+1)) / nb_jobs;
291 const int linesize = s->linesize[0];
292 int x, y;
293
294 for (y = start; y < end; y++) {
295 int sy = y << vsub;
296 for (x = 0; x < w; x++) {
297 int u, v, subU, subV, sum, sx;
298
299 sx = x << hsub;
300 u = s->pv[sx + sy * linesize][0] >> hsub;
301 v = s->pv[sx + sy * linesize][1] >> vsub;
302 subU = u & (SUB_PIXELS - 1);
303 subV = v & (SUB_PIXELS - 1);
304 u >>= SUB_PIXEL_BITS;
305 v >>= SUB_PIXEL_BITS;
306
307 if (u > 0 && v > 0 && u < w - 2 && v < h - 2){
308 const int index = u + v*src_linesize;
309 const int a = s->coeff[subU][0];
310 const int b = s->coeff[subU][1];
311 const int c = s->coeff[subU][2];
312 const int d = s->coeff[subU][3];
313
314 sum = s->coeff[subV][0] * (a * src[index - 1 - src_linesize] + b * src[index - 0 - src_linesize] +
315 c * src[index + 1 - src_linesize] + d * src[index + 2 - src_linesize]) +
316 s->coeff[subV][1] * (a * src[index - 1 ] + b * src[index - 0 ] +
317 c * src[index + 1 ] + d * src[index + 2 ]) +
318 s->coeff[subV][2] * (a * src[index - 1 + src_linesize] + b * src[index - 0 + src_linesize] +
319 c * src[index + 1 + src_linesize] + d * src[index + 2 + src_linesize]) +
320 s->coeff[subV][3] * (a * src[index - 1 + 2 * src_linesize] + b * src[index - 0 + 2 * src_linesize] +
321 c * src[index + 1 + 2 * src_linesize] + d * src[index + 2 + 2 * src_linesize]);
322 } else {
323 int dx, dy;
324
325 sum = 0;
326
327 for (dy = 0; dy < 4; dy++) {
328 int iy = v + dy - 1;
329
330 if (iy < 0)
331 iy = 0;
332 else if (iy >= h)
333 iy = h-1;
334 for (dx = 0; dx < 4; dx++) {
335 int ix = u + dx - 1;
336
337 if (ix < 0)
338 ix = 0;
339 else if (ix >= w)
340 ix = w - 1;
341
342 sum += s->coeff[subU][dx] * s->coeff[subV][dy] * src[ ix + iy * src_linesize];
343 }
344 }
345 }
346
347 sum = (sum + (1<<(COEFF_BITS * 2 - 1))) >> (COEFF_BITS * 2);
348 sum = av_clip_uint8(sum);
349 dst[x + y * dst_linesize] = sum;
350 }
351 }
352 return 0;
353 }
354
355 static int resample_linear(AVFilterContext *ctx, void *arg,
356 int job, int nb_jobs)
357 {
358 PerspectiveContext *s = ctx->priv;
359 ThreadData *td = arg;
360 uint8_t *dst = td->dst;
361 int dst_linesize = td->dst_linesize;
362 uint8_t *src = td->src;
363 int src_linesize = td->src_linesize;
364 int w = td->w;
365 int h = td->h;
366 int hsub = td->hsub;
367 int vsub = td->vsub;
368 int start = (h * job) / nb_jobs;
369 int end = (h * (job+1)) / nb_jobs;
370 const int linesize = s->linesize[0];
371 int x, y;
372
373 for (y = start; y < end; y++){
374 int sy = y << vsub;
375 for (x = 0; x < w; x++){
376 int u, v, subU, subV, sum, sx, index, subUI, subVI;
377
378 sx = x << hsub;
379 u = s->pv[sx + sy * linesize][0] >> hsub;
380 v = s->pv[sx + sy * linesize][1] >> vsub;
381 subU = u & (SUB_PIXELS - 1);
382 subV = v & (SUB_PIXELS - 1);
383 u >>= SUB_PIXEL_BITS;
384 v >>= SUB_PIXEL_BITS;
385
386 index = u + v * src_linesize;
387 subUI = SUB_PIXELS - subU;
388 subVI = SUB_PIXELS - subV;
389
390 if ((unsigned)u < (unsigned)(w - 1)){
391 if((unsigned)v < (unsigned)(h - 1)){
392 sum = subVI * (subUI * src[index] + subU * src[index + 1]) +
393 subV * (subUI * src[index + src_linesize] + subU * src[index + src_linesize + 1]);
394 sum = (sum + (1 << (SUB_PIXEL_BITS * 2 - 1)))>> (SUB_PIXEL_BITS * 2);
395 } else {
396 if (v < 0)
397 v = 0;
398 else
399 v = h - 1;
400 index = u + v * src_linesize;
401 sum = subUI * src[index] + subU * src[index + 1];
402 sum = (sum + (1 << (SUB_PIXEL_BITS - 1))) >> SUB_PIXEL_BITS;
403 }
404 } else {
405 if (u < 0)
406 u = 0;
407 else
408 u = w - 1;
409 if ((unsigned)v < (unsigned)(h - 1)){
410 index = u + v * src_linesize;
411 sum = subVI * src[index] + subV * src[index + src_linesize];
412 sum = (sum + (1 << (SUB_PIXEL_BITS - 1))) >> SUB_PIXEL_BITS;
413 } else {
414 if (v < 0)
415 v = 0;
416 else
417 v = h - 1;
418 index = u + v * src_linesize;
419 sum = src[index];
420 }
421 }
422
423 sum = av_clip_uint8(sum);
424 dst[x + y * dst_linesize] = sum;
425 }
426 }
427 return 0;
428 }
429
430 static av_cold int init(AVFilterContext *ctx)
431 {
432 PerspectiveContext *s = ctx->priv;
433
434 switch (s->interpolation) {
435 case LINEAR: s->perspective = resample_linear; break;
436 case CUBIC: s->perspective = resample_cubic; break;
437 }
438
439 return 0;
440 }
441
442 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
443 {
444 AVFilterContext *ctx = inlink->dst;
445 AVFilterLink *outlink = ctx->outputs[0];
446 PerspectiveContext *s = ctx->priv;
447 AVFrame *out;
448 int plane;
449 int ret;
450
451 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
452 if (!out) {
453 av_frame_free(&frame);
454 return AVERROR(ENOMEM);
455 }
456 av_frame_copy_props(out, frame);
457
458 if (s->eval_mode == EVAL_MODE_FRAME) {
459 if ((ret = calc_persp_luts(ctx, inlink)) < 0) {
460 av_frame_free(&out);
461 return ret;
462 }
463 }
464
465 for (plane = 0; plane < s->nb_planes; plane++) {
466 int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
467 int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
468 ThreadData td = {.dst = out->data[plane],
469 .dst_linesize = out->linesize[plane],
470 .src = frame->data[plane],
471 .src_linesize = frame->linesize[plane],
472 .w = s->linesize[plane],
473 .h = s->height[plane],
474 .hsub = hsub,
475 .vsub = vsub };
476 ff_filter_execute(ctx, s->perspective, &td, NULL,
477 FFMIN(td.h, ff_filter_get_nb_threads(ctx)));
478 }
479
480 av_frame_free(&frame);
481 return ff_filter_frame(outlink, out);
482 }
483
484 static av_cold void uninit(AVFilterContext *ctx)
485 {
486 PerspectiveContext *s = ctx->priv;
487
488 av_freep(&s->pv);
489 }
490
491 static const AVFilterPad perspective_inputs[] = {
492 {
493 .name = "default",
494 .type = AVMEDIA_TYPE_VIDEO,
495 .filter_frame = filter_frame,
496 .config_props = config_input,
497 },
498 };
499
500 const AVFilter ff_vf_perspective = {
501 .name = "perspective",
502 .description = NULL_IF_CONFIG_SMALL("Correct the perspective of video."),
503 .priv_size = sizeof(PerspectiveContext),
504 .init = init,
505 .uninit = uninit,
506 FILTER_INPUTS(perspective_inputs),
507 FILTER_OUTPUTS(ff_video_default_filterpad),
508 FILTER_PIXFMTS_ARRAY(pix_fmts),
509 .priv_class = &perspective_class,
510 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
511 };
512