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vf_fade.c
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1 /*
2  * Copyright (c) 2010 Brandon Mintern
3  * Copyright (c) 2007 Bobby Bingham
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  * video fade filter
25  * based heavily on vf_negate.c by Bobby Bingham
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "libavutil/avstring.h"
30 #include "libavutil/common.h"
31 #include "libavutil/eval.h"
32 #include "libavutil/opt.h"
33 #include "libavutil/pixdesc.h"
34 #include "avfilter.h"
35 #include "drawutils.h"
36 #include "formats.h"
37 #include "internal.h"
38 #include "video.h"
39 
40 #define R 0
41 #define G 1
42 #define B 2
43 #define A 3
44 
45 #define Y 0
46 #define U 1
47 #define V 2
48 
49 #define FADE_IN 0
50 #define FADE_OUT 1
51 
52 typedef struct {
53  const AVClass *class;
54  int type;
56  int start_frame, nb_frames;
57  int hsub, vsub, bpp;
58  unsigned int black_level, black_level_scaled;
60  uint8_t rgba_map[4];
61  int alpha;
62  uint64_t start_time, duration;
63  enum {VF_FADE_WAITING=0, VF_FADE_FADING, VF_FADE_DONE} fade_state;
64  uint8_t color_rgba[4]; ///< fade color
65  int black_fade; ///< if color_rgba is black
66 } FadeContext;
67 
68 static av_cold int init(AVFilterContext *ctx)
69 {
70  FadeContext *s = ctx->priv;
71 
72  s->fade_per_frame = (1 << 16) / s->nb_frames;
73  s->fade_state = VF_FADE_WAITING;
74 
75  if (s->duration != 0) {
76  // If duration (seconds) is non-zero, assume that we are not fading based on frames
77  s->nb_frames = 0; // Mostly to clean up logging
78  }
79 
80  // Choose what to log. If both time-based and frame-based options, both lines will be in the log
81  if (s->start_frame || s->nb_frames) {
83  "type:%s start_frame:%d nb_frames:%d alpha:%d\n",
84  s->type == FADE_IN ? "in" : "out", s->start_frame,
85  s->nb_frames,s->alpha);
86  }
87  if (s->start_time || s->duration) {
89  "type:%s start_time:%f duration:%f alpha:%d\n",
90  s->type == FADE_IN ? "in" : "out", (s->start_time / (double)AV_TIME_BASE),
91  (s->duration / (double)AV_TIME_BASE),s->alpha);
92  }
93 
94  s->black_fade = !memcmp(s->color_rgba, "\x00\x00\x00\xff", 4);
95  return 0;
96 }
97 
99 {
100  const FadeContext *s = ctx->priv;
101  static const enum AVPixelFormat pix_fmts[] = {
111  };
112  static const enum AVPixelFormat pix_fmts_rgb[] = {
117  };
118 
119  if (s->black_fade)
121  else
122  ff_set_common_formats(ctx, ff_make_format_list(pix_fmts_rgb));
123  return 0;
124 }
125 
126 const static enum AVPixelFormat studio_level_pix_fmts[] = {
131 };
132 
133 static int config_props(AVFilterLink *inlink)
134 {
135  FadeContext *s = inlink->dst->priv;
136  const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
137 
138  s->hsub = pixdesc->log2_chroma_w;
139  s->vsub = pixdesc->log2_chroma_h;
140 
141  s->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
142  s->alpha &= !!(pixdesc->flags & AV_PIX_FMT_FLAG_ALPHA);
143  s->is_packed_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
144 
145  /* use CCIR601/709 black level for studio-level pixel non-alpha components */
146  s->black_level =
147  ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !s->alpha ? 16 : 0;
148  /* 32768 = 1 << 15, it is an integer representation
149  * of 0.5 and is for rounding. */
150  s->black_level_scaled = (s->black_level << 16) + 32768;
151  return 0;
152 }
153 
155  int slice_start, int slice_end,
156  int do_alpha, int step)
157 {
158  int i, j;
159  const uint8_t r_idx = s->rgba_map[R];
160  const uint8_t g_idx = s->rgba_map[G];
161  const uint8_t b_idx = s->rgba_map[B];
162  const uint8_t a_idx = s->rgba_map[A];
163  const uint8_t *c = s->color_rgba;
164 
165  for (i = slice_start; i < slice_end; i++) {
166  uint8_t *p = frame->data[0] + i * frame->linesize[0];
167  for (j = 0; j < frame->width; j++) {
168 #define INTERP(c_name, c_idx) av_clip_uint8(((c[c_idx]<<16) + ((int)p[c_name] - (int)c[c_idx]) * s->factor + (1<<15)) >> 16)
169  p[r_idx] = INTERP(r_idx, 0);
170  p[g_idx] = INTERP(g_idx, 1);
171  p[b_idx] = INTERP(b_idx, 2);
172  if (do_alpha)
173  p[a_idx] = INTERP(a_idx, 3);
174  p += step;
175  }
176  }
177 }
178 
179 static int filter_slice_rgb(AVFilterContext *ctx, void *arg, int jobnr,
180  int nb_jobs)
181 {
182  FadeContext *s = ctx->priv;
183  AVFrame *frame = arg;
184  int slice_start = (frame->height * jobnr ) / nb_jobs;
185  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
186 
187  if (s->alpha) filter_rgb(s, frame, slice_start, slice_end, 1, 4);
188  else if (s->bpp == 3) filter_rgb(s, frame, slice_start, slice_end, 0, 3);
189  else if (s->bpp == 4) filter_rgb(s, frame, slice_start, slice_end, 0, 4);
190  else av_assert0(0);
191 
192  return 0;
193 }
194 
195 static int filter_slice_luma(AVFilterContext *ctx, void *arg, int jobnr,
196  int nb_jobs)
197 {
198  FadeContext *s = ctx->priv;
199  AVFrame *frame = arg;
200  int slice_start = (frame->height * jobnr ) / nb_jobs;
201  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
202  int i, j;
203 
204  for (i = slice_start; i < slice_end; i++) {
205  uint8_t *p = frame->data[0] + i * frame->linesize[0];
206  for (j = 0; j < frame->width * s->bpp; j++) {
207  /* s->factor is using 16 lower-order bits for decimal
208  * places. 32768 = 1 << 15, it is an integer representation
209  * of 0.5 and is for rounding. */
210  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
211  p++;
212  }
213  }
214 
215  return 0;
216 }
217 
218 static int filter_slice_chroma(AVFilterContext *ctx, void *arg, int jobnr,
219  int nb_jobs)
220 {
221  FadeContext *s = ctx->priv;
222  AVFrame *frame = arg;
223  int i, j, plane;
224  const int width = FF_CEIL_RSHIFT(frame->width, s->hsub);
225  const int height= FF_CEIL_RSHIFT(frame->height, s->vsub);
226  int slice_start = (height * jobnr ) / nb_jobs;
227  int slice_end = (height * (jobnr+1)) / nb_jobs;
228 
229  for (plane = 1; plane < 3; plane++) {
230  for (i = slice_start; i < slice_end; i++) {
231  uint8_t *p = frame->data[plane] + i * frame->linesize[plane];
232  for (j = 0; j < width; j++) {
233  /* 8421367 = ((128 << 1) + 1) << 15. It is an integer
234  * representation of 128.5. The .5 is for rounding
235  * purposes. */
236  *p = ((*p - 128) * s->factor + 8421367) >> 16;
237  p++;
238  }
239  }
240  }
241 
242  return 0;
243 }
244 
245 static int filter_slice_alpha(AVFilterContext *ctx, void *arg, int jobnr,
246  int nb_jobs)
247 {
248  FadeContext *s = ctx->priv;
249  AVFrame *frame = arg;
250  int plane = s->is_packed_rgb ? 0 : A;
251  int slice_start = (frame->height * jobnr ) / nb_jobs;
252  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
253  int i, j;
254 
255  for (i = slice_start; i < slice_end; i++) {
256  uint8_t *p = frame->data[plane] + i * frame->linesize[plane] + s->is_packed_rgb*s->rgba_map[A];
257  int step = s->is_packed_rgb ? 4 : 1;
258  for (j = 0; j < frame->width; j++) {
259  /* s->factor is using 16 lower-order bits for decimal
260  * places. 32768 = 1 << 15, it is an integer representation
261  * of 0.5 and is for rounding. */
262  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
263  p += step;
264  }
265  }
266 
267  return 0;
268 }
269 
270 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
271 {
272  AVFilterContext *ctx = inlink->dst;
273  FadeContext *s = ctx->priv;
274  double frame_timestamp = frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base);
275 
276  // Calculate Fade assuming this is a Fade In
277  if (s->fade_state == VF_FADE_WAITING) {
278  s->factor=0;
279  if (frame_timestamp >= s->start_time/(double)AV_TIME_BASE
280  && inlink->frame_count >= s->start_frame) {
281  // Time to start fading
282  s->fade_state = VF_FADE_FADING;
283 
284  // Save start time in case we are starting based on frames and fading based on time
285  if (s->start_time == 0 && s->start_frame != 0) {
286  s->start_time = frame_timestamp*(double)AV_TIME_BASE;
287  }
288 
289  // Save start frame in case we are starting based on time and fading based on frames
290  if (s->start_time != 0 && s->start_frame == 0) {
291  s->start_frame = inlink->frame_count;
292  }
293  }
294  }
295  if (s->fade_state == VF_FADE_FADING) {
296  if (s->duration == 0) {
297  // Fading based on frame count
298  s->factor = (inlink->frame_count - s->start_frame) * s->fade_per_frame;
299  if (inlink->frame_count > s->start_frame + s->nb_frames) {
300  s->fade_state = VF_FADE_DONE;
301  }
302 
303  } else {
304  // Fading based on duration
305  s->factor = (frame_timestamp - s->start_time/(double)AV_TIME_BASE)
306  * (float) UINT16_MAX / (s->duration/(double)AV_TIME_BASE);
307  if (frame_timestamp > s->start_time/(double)AV_TIME_BASE
308  + s->duration/(double)AV_TIME_BASE) {
309  s->fade_state = VF_FADE_DONE;
310  }
311  }
312  }
313  if (s->fade_state == VF_FADE_DONE) {
314  s->factor=UINT16_MAX;
315  }
316 
317  s->factor = av_clip_uint16(s->factor);
318 
319  // Invert fade_factor if Fading Out
320  if (s->type == FADE_OUT) {
321  s->factor=UINT16_MAX-s->factor;
322  }
323 
324  if (s->factor < UINT16_MAX) {
325  if (s->alpha) {
326  ctx->internal->execute(ctx, filter_slice_alpha, frame, NULL,
327  FFMIN(frame->height, ctx->graph->nb_threads));
328  } else if (s->is_packed_rgb && !s->black_fade) {
329  ctx->internal->execute(ctx, filter_slice_rgb, frame, NULL,
330  FFMIN(frame->height, ctx->graph->nb_threads));
331  } else {
332  /* luma, or rgb plane in case of black */
333  ctx->internal->execute(ctx, filter_slice_luma, frame, NULL,
334  FFMIN(frame->height, ctx->graph->nb_threads));
335 
336  if (frame->data[1] && frame->data[2]) {
337  /* chroma planes */
338  ctx->internal->execute(ctx, filter_slice_chroma, frame, NULL,
339  FFMIN(frame->height, ctx->graph->nb_threads));
340  }
341  }
342  }
343 
344  return ff_filter_frame(inlink->dst->outputs[0], frame);
345 }
346 
347 
348 #define OFFSET(x) offsetof(FadeContext, x)
349 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
350 
351 static const AVOption fade_options[] = {
352  { "type", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
353  { "t", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
354  { "in", "fade-in", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_IN }, .unit = "type" },
355  { "out", "fade-out", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_OUT }, .unit = "type" },
356  { "start_frame", "Number of the first frame to which to apply the effect.",
357  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
358  { "s", "Number of the first frame to which to apply the effect.",
359  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
360  { "nb_frames", "Number of frames to which the effect should be applied.",
361  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
362  { "n", "Number of frames to which the effect should be applied.",
363  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
364  { "alpha", "fade alpha if it is available on the input", OFFSET(alpha), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, FLAGS },
365  { "start_time", "Number of seconds of the beginning of the effect.",
366  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
367  { "st", "Number of seconds of the beginning of the effect.",
368  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
369  { "duration", "Duration of the effect in seconds.",
370  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
371  { "d", "Duration of the effect in seconds.",
372  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
373  { "color", "set color", OFFSET(color_rgba), AV_OPT_TYPE_COLOR, {.str = "black"}, CHAR_MIN, CHAR_MAX, FLAGS },
374  { "c", "set color", OFFSET(color_rgba), AV_OPT_TYPE_COLOR, {.str = "black"}, CHAR_MIN, CHAR_MAX, FLAGS },
375  { NULL }
376 };
377 
379 
381  {
382  .name = "default",
383  .type = AVMEDIA_TYPE_VIDEO,
384  .config_props = config_props,
385  .filter_frame = filter_frame,
386  .needs_writable = 1,
387  },
388  { NULL }
389 };
390 
392  {
393  .name = "default",
394  .type = AVMEDIA_TYPE_VIDEO,
395  },
396  { NULL }
397 };
398 
400  .name = "fade",
401  .description = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
402  .init = init,
403  .priv_size = sizeof(FadeContext),
404  .priv_class = &fade_class,
406  .inputs = avfilter_vf_fade_inputs,
407  .outputs = avfilter_vf_fade_outputs,
409 };