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vf_telecine.c
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1 /*
2  * Copyright (c) 2012 Rudolf Polzer
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 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 telecine filter, heavily based from mpv-player:TOOLS/vf_dlopen/telecine.c by
24  * Rudolf Polzer.
25  */
26 
27 #include "libavutil/avstring.h"
28 #include "libavutil/imgutils.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/pixdesc.h"
31 #include "avfilter.h"
32 #include "formats.h"
33 #include "internal.h"
34 #include "video.h"
35 
36 typedef struct {
37  const AVClass *class;
39  char *pattern;
40  unsigned int pattern_pos;
41 
43  double ts_unit;
44  int out_cnt;
45  int occupied;
46 
47  int nb_planes;
48  int planeheight[4];
49  int stride[4];
50 
54 
55 #define OFFSET(x) offsetof(TelecineContext, x)
56 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
57 
58 static const AVOption telecine_options[] = {
59  {"first_field", "select first field", OFFSET(first_field), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, "field"},
60  {"top", "select top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
61  {"t", "select top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
62  {"bottom", "select bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
63  {"b", "select bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
64  {"pattern", "pattern that describe for how many fields a frame is to be displayed", OFFSET(pattern), AV_OPT_TYPE_STRING, {.str="23"}, 0, 0, FLAGS},
65  {NULL}
66 };
67 
68 AVFILTER_DEFINE_CLASS(telecine);
69 
70 static av_cold int init(AVFilterContext *ctx)
71 {
72  TelecineContext *tc = ctx->priv;
73  const char *p;
74  int max = 0;
75 
76  if (!strlen(tc->pattern)) {
77  av_log(ctx, AV_LOG_ERROR, "No pattern provided.\n");
78  return AVERROR_INVALIDDATA;
79  }
80 
81  for (p = tc->pattern; *p; p++) {
82  if (!av_isdigit(*p)) {
83  av_log(ctx, AV_LOG_ERROR, "Provided pattern includes non-numeric characters.\n");
84  return AVERROR_INVALIDDATA;
85  }
86 
87  max = FFMAX(*p - '0', max);
88  tc->pts.num += 2;
89  tc->pts.den += *p - '0';
90  }
91 
92  tc->out_cnt = (max + 1) / 2;
93  av_log(ctx, AV_LOG_INFO, "Telecine pattern %s yields up to %d frames per frame, pts advance factor: %d/%d\n",
94  tc->pattern, tc->out_cnt, tc->pts.num, tc->pts.den);
95 
96  return 0;
97 }
98 
100 {
101  AVFilterFormats *pix_fmts = NULL;
102  int fmt;
103 
104  for (fmt = 0; fmt < AV_PIX_FMT_NB; fmt++) {
105  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
106  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
107  ff_add_format(&pix_fmts, fmt);
108  }
109 
110  ff_set_common_formats(ctx, pix_fmts);
111  return 0;
112 }
113 
114 static int config_input(AVFilterLink *inlink)
115 {
116  TelecineContext *tc = inlink->dst->priv;
117  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
118  int i, ret;
119 
120  tc->temp = ff_get_video_buffer(inlink, inlink->w, inlink->h);
121  if (!tc->temp)
122  return AVERROR(ENOMEM);
123  for (i = 0; i < tc->out_cnt; i++) {
124  tc->frame[i] = ff_get_video_buffer(inlink, inlink->w, inlink->h);
125  if (!tc->frame[i])
126  return AVERROR(ENOMEM);
127  }
128 
129  if ((ret = av_image_fill_linesizes(tc->stride, inlink->format, inlink->w)) < 0)
130  return ret;
131 
132  tc->planeheight[1] = tc->planeheight[2] = FF_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
133  tc->planeheight[0] = tc->planeheight[3] = inlink->h;
134 
136 
137  return 0;
138 }
139 
140 static int config_output(AVFilterLink *outlink)
141 {
142  AVFilterContext *ctx = outlink->src;
143  TelecineContext *tc = ctx->priv;
144  const AVFilterLink *inlink = ctx->inputs[0];
145  AVRational fps = inlink->frame_rate;
146 
147  if (!fps.num || !fps.den) {
148  av_log(ctx, AV_LOG_ERROR, "The input needs a constant frame rate; "
149  "current rate of %d/%d is invalid\n", fps.num, fps.den);
150  return AVERROR(EINVAL);
151  }
152  fps = av_mul_q(fps, av_inv_q(tc->pts));
153  av_log(ctx, AV_LOG_VERBOSE, "FPS: %d/%d -> %d/%d\n",
154  inlink->frame_rate.num, inlink->frame_rate.den, fps.num, fps.den);
155 
156  outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
157  outlink->frame_rate = fps;
158  outlink->time_base = av_mul_q(inlink->time_base, tc->pts);
159  av_log(ctx, AV_LOG_VERBOSE, "TB: %d/%d -> %d/%d\n",
160  inlink->time_base.num, inlink->time_base.den, outlink->time_base.num, outlink->time_base.den);
161 
162  tc->ts_unit = av_q2d(av_inv_q(av_mul_q(fps, outlink->time_base)));
163 
164  return 0;
165 }
166 
167 static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
168 {
169  AVFilterContext *ctx = inlink->dst;
170  AVFilterLink *outlink = ctx->outputs[0];
171  TelecineContext *tc = ctx->priv;
172  int i, len, ret = 0, nout = 0;
173 
174  len = tc->pattern[tc->pattern_pos] - '0';
175 
176  tc->pattern_pos++;
177  if (!tc->pattern[tc->pattern_pos])
178  tc->pattern_pos = 0;
179 
180  if (!len) { // do not output any field from this frame
181  av_frame_free(&inpicref);
182  return 0;
183  }
184 
185  if (tc->occupied) {
186  for (i = 0; i < tc->nb_planes; i++) {
187  // fill in the EARLIER field from the buffered pic
188  av_image_copy_plane(tc->frame[nout]->data[i] + tc->frame[nout]->linesize[i] * tc->first_field,
189  tc->frame[nout]->linesize[i] * 2,
190  tc->temp->data[i] + tc->temp->linesize[i] * tc->first_field,
191  tc->temp->linesize[i] * 2,
192  tc->stride[i],
193  (tc->planeheight[i] - tc->first_field + 1) / 2);
194  // fill in the LATER field from the new pic
195  av_image_copy_plane(tc->frame[nout]->data[i] + tc->frame[nout]->linesize[i] * !tc->first_field,
196  tc->frame[nout]->linesize[i] * 2,
197  inpicref->data[i] + inpicref->linesize[i] * !tc->first_field,
198  inpicref->linesize[i] * 2,
199  tc->stride[i],
200  (tc->planeheight[i] - !tc->first_field + 1) / 2);
201  }
202  nout++;
203  len--;
204  tc->occupied = 0;
205  }
206 
207  while (len >= 2) {
208  // output THIS image as-is
209  for (i = 0; i < tc->nb_planes; i++)
210  av_image_copy_plane(tc->frame[nout]->data[i], tc->frame[nout]->linesize[i],
211  inpicref->data[i], inpicref->linesize[i],
212  tc->stride[i],
213  tc->planeheight[i]);
214  nout++;
215  len -= 2;
216  }
217 
218  if (len >= 1) {
219  // copy THIS image to the buffer, we need it later
220  for (i = 0; i < tc->nb_planes; i++)
221  av_image_copy_plane(tc->temp->data[i], tc->temp->linesize[i],
222  inpicref->data[i], inpicref->linesize[i],
223  tc->stride[i],
224  tc->planeheight[i]);
225  tc->occupied = 1;
226  }
227 
228  for (i = 0; i < nout; i++) {
229  AVFrame *frame = av_frame_clone(tc->frame[i]);
230 
231  if (!frame) {
232  av_frame_free(&inpicref);
233  return AVERROR(ENOMEM);
234  }
235 
236  av_frame_copy_props(frame, inpicref);
237  frame->pts = outlink->frame_count * tc->ts_unit;
238  ret = ff_filter_frame(outlink, frame);
239  }
240  av_frame_free(&inpicref);
241 
242  return ret;
243 }
244 
245 static av_cold void uninit(AVFilterContext *ctx)
246 {
247  TelecineContext *tc = ctx->priv;
248  int i;
249 
250  av_frame_free(&tc->temp);
251  for (i = 0; i < tc->out_cnt; i++)
252  av_frame_free(&tc->frame[i]);
253 }
254 
255 static const AVFilterPad telecine_inputs[] = {
256  {
257  .name = "default",
258  .type = AVMEDIA_TYPE_VIDEO,
259  .filter_frame = filter_frame,
260  .config_props = config_input,
261  },
262  { NULL }
263 };
264 
265 static const AVFilterPad telecine_outputs[] = {
266  {
267  .name = "default",
268  .type = AVMEDIA_TYPE_VIDEO,
269  .config_props = config_output,
270  },
271  { NULL }
272 };
273 
275  .name = "telecine",
276  .description = NULL_IF_CONFIG_SMALL("Apply a telecine pattern."),
277  .priv_size = sizeof(TelecineContext),
278  .priv_class = &telecine_class,
279  .init = init,
280  .uninit = uninit,
282  .inputs = telecine_inputs,
283  .outputs = telecine_outputs,
284 };