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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/avstring.h"
29 #include "libavutil/common.h"
30 #include "libavutil/eval.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/pixdesc.h"
33 #include "avfilter.h"
34 #include "drawutils.h"
35 #include "internal.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  unsigned int frame_index;
58  int hsub, vsub, bpp;
59  unsigned int black_level, black_level_scaled;
61  uint8_t rgba_map[4];
62  int alpha;
63  uint64_t start_time, duration;
64  enum {VF_FADE_WAITING=0, VF_FADE_FADING, VF_FADE_DONE} fade_state;
65 } FadeContext;
66 
67 static av_cold int init(AVFilterContext *ctx)
68 {
69  FadeContext *s = ctx->priv;
70 
71  s->fade_per_frame = (1 << 16) / s->nb_frames;
72  s->fade_state = VF_FADE_WAITING;
73 
74  if (s->duration != 0) {
75  // If duration (seconds) is non-zero, assume that we are not fading based on frames
76  s->nb_frames = 0; // Mostly to clean up logging
77  }
78 
79  // Choose what to log. If both time-based and frame-based options, both lines will be in the log
80  if (s->start_frame || s->nb_frames) {
82  "type:%s start_frame:%d nb_frames:%d alpha:%d\n",
83  s->type == FADE_IN ? "in" : "out", s->start_frame,
84  s->nb_frames,s->alpha);
85  }
86  if (s->start_time || s->duration) {
88  "type:%s start_time:%f duration:%f alpha:%d\n",
89  s->type == FADE_IN ? "in" : "out", (s->start_time / (double)AV_TIME_BASE),
90  (s->duration / (double)AV_TIME_BASE),s->alpha);
91  }
92 
93  return 0;
94 }
95 
97 {
98  static const enum AVPixelFormat pix_fmts[] = {
108  };
109 
111  return 0;
112 }
113 
114 const static enum AVPixelFormat studio_level_pix_fmts[] = {
119 };
120 
121 static int config_props(AVFilterLink *inlink)
122 {
123  FadeContext *s = inlink->dst->priv;
124  const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
125 
126  s->hsub = pixdesc->log2_chroma_w;
127  s->vsub = pixdesc->log2_chroma_h;
128 
129  s->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
130  s->alpha &= !!(pixdesc->flags & AV_PIX_FMT_FLAG_ALPHA);
131  s->is_packed_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
132 
133  /* use CCIR601/709 black level for studio-level pixel non-alpha components */
134  s->black_level =
135  ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !s->alpha ? 16 : 0;
136  /* 32768 = 1 << 15, it is an integer representation
137  * of 0.5 and is for rounding. */
138  s->black_level_scaled = (s->black_level << 16) + 32768;
139  return 0;
140 }
141 
142 static int filter_slice_luma(AVFilterContext *ctx, void *arg, int jobnr,
143  int nb_jobs)
144 {
145  FadeContext *s = ctx->priv;
146  AVFrame *frame = arg;
147  int slice_start = (frame->height * jobnr ) / nb_jobs;
148  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
149  int i, j;
150 
151  for (i = slice_start; i < slice_end; i++) {
152  uint8_t *p = frame->data[0] + i * frame->linesize[0];
153  for (j = 0; j < frame->width * s->bpp; j++) {
154  /* s->factor is using 16 lower-order bits for decimal
155  * places. 32768 = 1 << 15, it is an integer representation
156  * of 0.5 and is for rounding. */
157  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
158  p++;
159  }
160  }
161 
162  return 0;
163 }
164 
165 static int filter_slice_chroma(AVFilterContext *ctx, void *arg, int jobnr,
166  int nb_jobs)
167 {
168  FadeContext *s = ctx->priv;
169  AVFrame *frame = arg;
170  int i, j, plane;
171  const int width = FF_CEIL_RSHIFT(frame->width, s->hsub);
172  const int height= FF_CEIL_RSHIFT(frame->height, s->vsub);
173  int slice_start = (height * jobnr ) / nb_jobs;
174  int slice_end = (height * (jobnr+1)) / nb_jobs;
175 
176  for (plane = 1; plane < 3; plane++) {
177  for (i = slice_start; i < slice_end; i++) {
178  uint8_t *p = frame->data[plane] + i * frame->linesize[plane];
179  for (j = 0; j < width; j++) {
180  /* 8421367 = ((128 << 1) + 1) << 15. It is an integer
181  * representation of 128.5. The .5 is for rounding
182  * purposes. */
183  *p = ((*p - 128) * s->factor + 8421367) >> 16;
184  p++;
185  }
186  }
187  }
188 
189  return 0;
190 }
191 
192 static int filter_slice_alpha(AVFilterContext *ctx, void *arg, int jobnr,
193  int nb_jobs)
194 {
195  FadeContext *s = ctx->priv;
196  AVFrame *frame = arg;
197  int plane = s->is_packed_rgb ? 0 : A;
198  int slice_start = (frame->height * jobnr ) / nb_jobs;
199  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
200  int i, j;
201 
202  for (i = slice_start; i < slice_end; i++) {
203  uint8_t *p = frame->data[plane] + i * frame->linesize[plane] + s->is_packed_rgb*s->rgba_map[A];
204  int step = s->is_packed_rgb ? 4 : 1;
205  for (j = 0; j < frame->width; j++) {
206  /* s->factor is using 16 lower-order bits for decimal
207  * places. 32768 = 1 << 15, it is an integer representation
208  * of 0.5 and is for rounding. */
209  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
210  p += step;
211  }
212  }
213 
214  return 0;
215 }
216 
217 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
218 {
219  AVFilterContext *ctx = inlink->dst;
220  FadeContext *s = ctx->priv;
221  double frame_timestamp = frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base);
222 
223  // Calculate Fade assuming this is a Fade In
224  if (s->fade_state == VF_FADE_WAITING) {
225  s->factor=0;
226  if ((frame_timestamp >= (s->start_time/(double)AV_TIME_BASE))
227  && (s->frame_index >= s->start_frame)) {
228  // Time to start fading
229  s->fade_state = VF_FADE_FADING;
230 
231  // Save start time in case we are starting based on frames and fading based on time
232  if ((s->start_time == 0) && (s->start_frame != 0)) {
233  s->start_time = frame_timestamp*(double)AV_TIME_BASE;
234  }
235 
236  // Save start frame in case we are starting based on time and fading based on frames
237  if ((s->start_time != 0) && (s->start_frame == 0)) {
238  s->start_frame = s->frame_index;
239  }
240  }
241  }
242  if (s->fade_state == VF_FADE_FADING) {
243  if (s->duration == 0) {
244  // Fading based on frame count
245  s->factor = (s->frame_index - s->start_frame) * s->fade_per_frame;
246  if (s->frame_index > (s->start_frame + s->nb_frames)) {
247  s->fade_state = VF_FADE_DONE;
248  }
249 
250  } else {
251  // Fading based on duration
252  s->factor = (frame_timestamp - (s->start_time/(double)AV_TIME_BASE))
253  * (float) UINT16_MAX / (s->duration/(double)AV_TIME_BASE);
254  if (frame_timestamp > ((s->start_time/(double)AV_TIME_BASE)
255  + (s->duration/(double)AV_TIME_BASE))) {
256  s->fade_state = VF_FADE_DONE;
257  }
258  }
259  }
260  if (s->fade_state == VF_FADE_DONE) {
261  s->factor=UINT16_MAX;
262  }
263 
264  s->factor = av_clip_uint16(s->factor);
265 
266  // Invert fade_factor if Fading Out
267  if (s->type == 1) {
268  s->factor=UINT16_MAX-s->factor;
269  }
270 
271  if (s->factor < UINT16_MAX) {
272  if (s->alpha) {
273  ctx->internal->execute(ctx, filter_slice_alpha, frame, NULL,
274  FFMIN(frame->height, ctx->graph->nb_threads));
275  } else {
276  /* luma or rgb plane */
277  ctx->internal->execute(ctx, filter_slice_luma, frame, NULL,
278  FFMIN(frame->height, ctx->graph->nb_threads));
279 
280  if (frame->data[1] && frame->data[2]) {
281  /* chroma planes */
282  ctx->internal->execute(ctx, filter_slice_chroma, frame, NULL,
283  FFMIN(frame->height, ctx->graph->nb_threads));
284  }
285  }
286  }
287 
288  s->frame_index++;
289 
290  return ff_filter_frame(inlink->dst->outputs[0], frame);
291 }
292 
293 
294 #define OFFSET(x) offsetof(FadeContext, x)
295 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
296 
297 static const AVOption fade_options[] = {
298  { "type", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
299  { "t", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
300  { "in", "fade-in", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_IN }, .unit = "type" },
301  { "out", "fade-out", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_OUT }, .unit = "type" },
302  { "start_frame", "Number of the first frame to which to apply the effect.",
303  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
304  { "s", "Number of the first frame to which to apply the effect.",
305  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
306  { "nb_frames", "Number of frames to which the effect should be applied.",
307  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
308  { "n", "Number of frames to which the effect should be applied.",
309  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
310  { "alpha", "fade alpha if it is available on the input", OFFSET(alpha), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, FLAGS },
311  { "start_time", "Number of seconds of the beginning of the effect.",
312  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
313  { "st", "Number of seconds of the beginning of the effect.",
314  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
315  { "duration", "Duration of the effect in seconds.",
316  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
317  { "d", "Duration of the effect in seconds.",
318  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
319  { NULL },
320 };
321 
323 
325  {
326  .name = "default",
327  .type = AVMEDIA_TYPE_VIDEO,
328  .config_props = config_props,
329  .get_video_buffer = ff_null_get_video_buffer,
330  .filter_frame = filter_frame,
331  .needs_writable = 1,
332  },
333  { NULL }
334 };
335 
337  {
338  .name = "default",
339  .type = AVMEDIA_TYPE_VIDEO,
340  },
341  { NULL }
342 };
343 
345  .name = "fade",
346  .description = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
347  .init = init,
348  .priv_size = sizeof(FadeContext),
349  .priv_class = &fade_class,
351 
352  .inputs = avfilter_vf_fade_inputs,
353  .outputs = avfilter_vf_fade_outputs,
355 };