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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 "formats.h"
36 #include "internal.h"
37 #include "video.h"
38 
39 #define R 0
40 #define G 1
41 #define B 2
42 #define A 3
43 
44 #define Y 0
45 #define U 1
46 #define V 2
47 
48 #define FADE_IN 0
49 #define FADE_OUT 1
50 
51 typedef struct {
52  const AVClass *class;
53  int type;
55  int start_frame, nb_frames;
56  unsigned int frame_index;
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 } FadeContext;
65 
66 static av_cold int init(AVFilterContext *ctx)
67 {
68  FadeContext *s = ctx->priv;
69 
70  s->fade_per_frame = (1 << 16) / s->nb_frames;
71  s->fade_state = VF_FADE_WAITING;
72 
73  if (s->duration != 0) {
74  // If duration (seconds) is non-zero, assume that we are not fading based on frames
75  s->nb_frames = 0; // Mostly to clean up logging
76  }
77 
78  // Choose what to log. If both time-based and frame-based options, both lines will be in the log
79  if (s->start_frame || s->nb_frames) {
81  "type:%s start_frame:%d nb_frames:%d alpha:%d\n",
82  s->type == FADE_IN ? "in" : "out", s->start_frame,
83  s->nb_frames,s->alpha);
84  }
85  if (s->start_time || s->duration) {
87  "type:%s start_time:%f duration:%f alpha:%d\n",
88  s->type == FADE_IN ? "in" : "out", (s->start_time / (double)AV_TIME_BASE),
89  (s->duration / (double)AV_TIME_BASE),s->alpha);
90  }
91 
92  return 0;
93 }
94 
96 {
97  static const enum AVPixelFormat pix_fmts[] = {
107  };
108 
110  return 0;
111 }
112 
113 const static enum AVPixelFormat studio_level_pix_fmts[] = {
118 };
119 
120 static int config_props(AVFilterLink *inlink)
121 {
122  FadeContext *s = inlink->dst->priv;
123  const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
124 
125  s->hsub = pixdesc->log2_chroma_w;
126  s->vsub = pixdesc->log2_chroma_h;
127 
128  s->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
129  s->alpha &= !!(pixdesc->flags & AV_PIX_FMT_FLAG_ALPHA);
130  s->is_packed_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
131 
132  /* use CCIR601/709 black level for studio-level pixel non-alpha components */
133  s->black_level =
134  ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !s->alpha ? 16 : 0;
135  /* 32768 = 1 << 15, it is an integer representation
136  * of 0.5 and is for rounding. */
137  s->black_level_scaled = (s->black_level << 16) + 32768;
138  return 0;
139 }
140 
141 static int filter_slice_luma(AVFilterContext *ctx, void *arg, int jobnr,
142  int nb_jobs)
143 {
144  FadeContext *s = ctx->priv;
145  AVFrame *frame = arg;
146  int slice_start = (frame->height * jobnr ) / nb_jobs;
147  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
148  int i, j;
149 
150  for (i = slice_start; i < slice_end; i++) {
151  uint8_t *p = frame->data[0] + i * frame->linesize[0];
152  for (j = 0; j < frame->width * s->bpp; j++) {
153  /* s->factor is using 16 lower-order bits for decimal
154  * places. 32768 = 1 << 15, it is an integer representation
155  * of 0.5 and is for rounding. */
156  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
157  p++;
158  }
159  }
160 
161  return 0;
162 }
163 
164 static int filter_slice_chroma(AVFilterContext *ctx, void *arg, int jobnr,
165  int nb_jobs)
166 {
167  FadeContext *s = ctx->priv;
168  AVFrame *frame = arg;
169  int i, j, plane;
170  const int width = FF_CEIL_RSHIFT(frame->width, s->hsub);
171  const int height= FF_CEIL_RSHIFT(frame->height, s->vsub);
172  int slice_start = (height * jobnr ) / nb_jobs;
173  int slice_end = (height * (jobnr+1)) / nb_jobs;
174 
175  for (plane = 1; plane < 3; plane++) {
176  for (i = slice_start; i < slice_end; i++) {
177  uint8_t *p = frame->data[plane] + i * frame->linesize[plane];
178  for (j = 0; j < width; j++) {
179  /* 8421367 = ((128 << 1) + 1) << 15. It is an integer
180  * representation of 128.5. The .5 is for rounding
181  * purposes. */
182  *p = ((*p - 128) * s->factor + 8421367) >> 16;
183  p++;
184  }
185  }
186  }
187 
188  return 0;
189 }
190 
191 static int filter_slice_alpha(AVFilterContext *ctx, void *arg, int jobnr,
192  int nb_jobs)
193 {
194  FadeContext *s = ctx->priv;
195  AVFrame *frame = arg;
196  int plane = s->is_packed_rgb ? 0 : A;
197  int slice_start = (frame->height * jobnr ) / nb_jobs;
198  int slice_end = (frame->height * (jobnr+1)) / nb_jobs;
199  int i, j;
200 
201  for (i = slice_start; i < slice_end; i++) {
202  uint8_t *p = frame->data[plane] + i * frame->linesize[plane] + s->is_packed_rgb*s->rgba_map[A];
203  int step = s->is_packed_rgb ? 4 : 1;
204  for (j = 0; j < frame->width; j++) {
205  /* s->factor is using 16 lower-order bits for decimal
206  * places. 32768 = 1 << 15, it is an integer representation
207  * of 0.5 and is for rounding. */
208  *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
209  p += step;
210  }
211  }
212 
213  return 0;
214 }
215 
216 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
217 {
218  AVFilterContext *ctx = inlink->dst;
219  FadeContext *s = ctx->priv;
220  double frame_timestamp = frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base);
221 
222  // Calculate Fade assuming this is a Fade In
223  if (s->fade_state == VF_FADE_WAITING) {
224  s->factor=0;
225  if ((frame_timestamp >= (s->start_time/(double)AV_TIME_BASE))
226  && (s->frame_index >= s->start_frame)) {
227  // Time to start fading
228  s->fade_state = VF_FADE_FADING;
229 
230  // Save start time in case we are starting based on frames and fading based on time
231  if ((s->start_time == 0) && (s->start_frame != 0)) {
232  s->start_time = frame_timestamp*(double)AV_TIME_BASE;
233  }
234 
235  // Save start frame in case we are starting based on time and fading based on frames
236  if ((s->start_time != 0) && (s->start_frame == 0)) {
237  s->start_frame = s->frame_index;
238  }
239  }
240  }
241  if (s->fade_state == VF_FADE_FADING) {
242  if (s->duration == 0) {
243  // Fading based on frame count
244  s->factor = (s->frame_index - s->start_frame) * s->fade_per_frame;
245  if (s->frame_index > (s->start_frame + s->nb_frames)) {
246  s->fade_state = VF_FADE_DONE;
247  }
248 
249  } else {
250  // Fading based on duration
251  s->factor = (frame_timestamp - (s->start_time/(double)AV_TIME_BASE))
252  * (float) UINT16_MAX / (s->duration/(double)AV_TIME_BASE);
253  if (frame_timestamp > ((s->start_time/(double)AV_TIME_BASE)
254  + (s->duration/(double)AV_TIME_BASE))) {
255  s->fade_state = VF_FADE_DONE;
256  }
257  }
258  }
259  if (s->fade_state == VF_FADE_DONE) {
260  s->factor=UINT16_MAX;
261  }
262 
263  s->factor = av_clip_uint16(s->factor);
264 
265  // Invert fade_factor if Fading Out
266  if (s->type == 1) {
267  s->factor=UINT16_MAX-s->factor;
268  }
269 
270  if (s->factor < UINT16_MAX) {
271  if (s->alpha) {
272  ctx->internal->execute(ctx, filter_slice_alpha, frame, NULL,
273  FFMIN(frame->height, ctx->graph->nb_threads));
274  } else {
275  /* luma or rgb plane */
276  ctx->internal->execute(ctx, filter_slice_luma, frame, NULL,
277  FFMIN(frame->height, ctx->graph->nb_threads));
278 
279  if (frame->data[1] && frame->data[2]) {
280  /* chroma planes */
281  ctx->internal->execute(ctx, filter_slice_chroma, frame, NULL,
282  FFMIN(frame->height, ctx->graph->nb_threads));
283  }
284  }
285  }
286 
287  s->frame_index++;
288 
289  return ff_filter_frame(inlink->dst->outputs[0], frame);
290 }
291 
292 
293 #define OFFSET(x) offsetof(FadeContext, x)
294 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
295 
296 static const AVOption fade_options[] = {
297  { "type", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
298  { "t", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
299  { "in", "fade-in", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_IN }, .unit = "type" },
300  { "out", "fade-out", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_OUT }, .unit = "type" },
301  { "start_frame", "Number of the first frame to which to apply the effect.",
302  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
303  { "s", "Number of the first frame to which to apply the effect.",
304  OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
305  { "nb_frames", "Number of frames to which the effect should be applied.",
306  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
307  { "n", "Number of frames to which the effect should be applied.",
308  OFFSET(nb_frames), AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
309  { "alpha", "fade alpha if it is available on the input", OFFSET(alpha), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, FLAGS },
310  { "start_time", "Number of seconds of the beginning of the effect.",
311  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
312  { "st", "Number of seconds of the beginning of the effect.",
313  OFFSET(start_time), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
314  { "duration", "Duration of the effect in seconds.",
315  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
316  { "d", "Duration of the effect in seconds.",
317  OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
318  { NULL }
319 };
320 
322 
324  {
325  .name = "default",
326  .type = AVMEDIA_TYPE_VIDEO,
327  .config_props = config_props,
328  .filter_frame = filter_frame,
329  .needs_writable = 1,
330  },
331  { NULL }
332 };
333 
335  {
336  .name = "default",
337  .type = AVMEDIA_TYPE_VIDEO,
338  },
339  { NULL }
340 };
341 
343  .name = "fade",
344  .description = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
345  .init = init,
346  .priv_size = sizeof(FadeContext),
347  .priv_class = &fade_class,
349  .inputs = avfilter_vf_fade_inputs,
350  .outputs = avfilter_vf_fade_outputs,
352 };