1 /*
2 * Copyright (c) 2015 Himangi Saraogi <himangi774@gmail.com>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file detelecine filter.
23 */
24
25
26 #include "libavutil/avstring.h"
27 #include "libavutil/imgutils.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/pixdesc.h"
30 #include "avfilter.h"
31 #include "formats.h"
32 #include "internal.h"
33 #include "video.h"
34
35 typedef struct DetelecineContext {
36 const AVClass *class;
37 int first_field;
38 char *pattern;
39 int start_frame;
40 int init_len;
41 unsigned int pattern_pos;
42 unsigned int nskip_fields;
43 int64_t start_time;
44
45 AVRational pts;
46 AVRational ts_unit;
47 int occupied;
48
49 int nb_planes;
50 int planeheight[4];
51 int stride[4];
52
53 AVFrame *frame[2];
54 AVFrame *temp;
55 } DetelecineContext;
56
57 #define OFFSET(x) offsetof(DetelecineContext, x)
58 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
59
60 static const AVOption detelecine_options[] = {
61 {"first_field", "select first field", OFFSET(first_field), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, "field"},
62 {"top", "select top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
63 {"t", "select top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
64 {"bottom", "select bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
65 {"b", "select bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
66 {"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},
67 {"start_frame", "position of first frame with respect to the pattern if stream is cut", OFFSET(start_frame), AV_OPT_TYPE_INT, {.i64=0}, 0, 13, FLAGS},
68 {NULL}
69 };
70
71 AVFILTER_DEFINE_CLASS(detelecine);
72
init(AVFilterContext * ctx)73 static av_cold int init(AVFilterContext *ctx)
74 {
75 DetelecineContext *s = ctx->priv;
76 const char *p;
77 int max = 0;
78 int sum = 0;
79
80 if (!strlen(s->pattern)) {
81 av_log(ctx, AV_LOG_ERROR, "No pattern provided.\n");
82 return AVERROR_INVALIDDATA;
83 }
84
85 for (p = s->pattern; *p; p++) {
86 if (!av_isdigit(*p)) {
87 av_log(ctx, AV_LOG_ERROR, "Provided pattern includes non-numeric characters.\n");
88 return AVERROR_INVALIDDATA;
89 }
90
91 sum += *p - '0';
92 max = FFMAX(*p - '0', max);
93 s->pts.num += *p - '0';
94 s->pts.den += 2;
95 }
96
97 if (s->start_frame >= sum) {
98 av_log(ctx, AV_LOG_ERROR, "Provided start_frame is too big.\n");
99 return AVERROR_INVALIDDATA;
100 }
101
102 s->nskip_fields = 0;
103 s->pattern_pos = 0;
104 s->start_time = AV_NOPTS_VALUE;
105 s->init_len = 0;
106
107 if (s->start_frame != 0) {
108 int nfields = 0;
109 for (p = s->pattern; *p; p++) {
110 nfields += *p - '0';
111 s->pattern_pos++;
112 if (nfields >= 2*s->start_frame) {
113 s->init_len = nfields - 2*s->start_frame;
114 break;
115 }
116 }
117 }
118
119 av_log(ctx, AV_LOG_INFO, "Detelecine pattern %s removes up to %d frames per frame, pts advance factor: %d/%d\n",
120 s->pattern, (max + 1) / 2, s->pts.num, s->pts.den);
121
122 return 0;
123 }
124
query_formats(AVFilterContext * ctx)125 static int query_formats(AVFilterContext *ctx)
126 {
127 AVFilterFormats *formats = NULL;
128 int ret;
129
130 ret = ff_formats_pixdesc_filter(&formats, 0,
131 AV_PIX_FMT_FLAG_BITSTREAM |
132 AV_PIX_FMT_FLAG_PAL |
133 AV_PIX_FMT_FLAG_HWACCEL);
134 if (ret < 0)
135 return ret;
136 return ff_set_common_formats(ctx, formats);
137 }
138
config_input(AVFilterLink * inlink)139 static int config_input(AVFilterLink *inlink)
140 {
141 DetelecineContext *s = inlink->dst->priv;
142 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
143 int ret;
144
145 s->temp = ff_get_video_buffer(inlink, inlink->w, inlink->h);
146 if (!s->temp)
147 return AVERROR(ENOMEM);
148
149 s->frame[0] = ff_get_video_buffer(inlink, inlink->w, inlink->h);
150 if (!s->frame[0])
151 return AVERROR(ENOMEM);
152
153 s->frame[1] = ff_get_video_buffer(inlink, inlink->w, inlink->h);
154 if (!s->frame[1])
155 return AVERROR(ENOMEM);
156
157 if ((ret = av_image_fill_linesizes(s->stride, inlink->format, inlink->w)) < 0)
158 return ret;
159
160 s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
161 s->planeheight[0] = s->planeheight[3] = inlink->h;
162
163 s->nb_planes = av_pix_fmt_count_planes(inlink->format);
164
165 return 0;
166 }
167
config_output(AVFilterLink * outlink)168 static int config_output(AVFilterLink *outlink)
169 {
170 AVFilterContext *ctx = outlink->src;
171 DetelecineContext *s = ctx->priv;
172 const AVFilterLink *inlink = ctx->inputs[0];
173 AVRational fps = inlink->frame_rate;
174
175 if (!fps.num || !fps.den) {
176 av_log(ctx, AV_LOG_ERROR, "The input needs a constant frame rate; "
177 "current rate of %d/%d is invalid\n", fps.num, fps.den);
178 return AVERROR(EINVAL);
179 }
180 fps = av_mul_q(fps, av_inv_q(s->pts));
181 av_log(ctx, AV_LOG_VERBOSE, "FPS: %d/%d -> %d/%d\n",
182 inlink->frame_rate.num, inlink->frame_rate.den, fps.num, fps.den);
183
184 outlink->frame_rate = fps;
185 outlink->time_base = av_mul_q(inlink->time_base, s->pts);
186 av_log(ctx, AV_LOG_VERBOSE, "TB: %d/%d -> %d/%d\n",
187 inlink->time_base.num, inlink->time_base.den, outlink->time_base.num, outlink->time_base.den);
188
189 s->ts_unit = av_inv_q(av_mul_q(fps, outlink->time_base));
190
191 return 0;
192 }
193
filter_frame(AVFilterLink * inlink,AVFrame * inpicref)194 static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
195 {
196 AVFilterContext *ctx = inlink->dst;
197 AVFilterLink *outlink = ctx->outputs[0];
198 DetelecineContext *s = ctx->priv;
199 int i, len = 0, ret = 0, out = 0;
200
201 if (s->start_time == AV_NOPTS_VALUE)
202 s->start_time = inpicref->pts;
203
204 if (s->nskip_fields >= 2) {
205 s->nskip_fields -= 2;
206 av_frame_free(&inpicref);
207 return 0;
208 } else if (s->nskip_fields >= 1) {
209 for (i = 0; i < s->nb_planes; i++) {
210 av_image_copy_plane(s->temp->data[i], s->temp->linesize[i],
211 inpicref->data[i], inpicref->linesize[i],
212 s->stride[i],
213 s->planeheight[i]);
214 }
215 s->occupied = 1;
216 s->nskip_fields--;
217 av_frame_free(&inpicref);
218 return 0;
219 }
220
221 if (s->nskip_fields == 0) {
222 len = s->init_len;
223 s->init_len = 0;
224 while(!len && s->pattern[s->pattern_pos]) {
225 len = s->pattern[s->pattern_pos] - '0';
226 s->pattern_pos++;
227 }
228
229 if (!s->pattern[s->pattern_pos])
230 s->pattern_pos = 0;
231
232 if(!len) { // do not output any field as the entire pattern is zero
233 av_frame_free(&inpicref);
234 return 0;
235 }
236
237 if (len == 1 && s->occupied) {
238 s->occupied = 0;
239 // output THIS image as-is
240 for (i = 0; i < s->nb_planes; i++)
241 av_image_copy_plane(s->frame[out]->data[i], s->frame[out]->linesize[i],
242 s->temp->data[i], s->temp->linesize[i],
243 s->stride[i],
244 s->planeheight[i]);
245 len = 0;
246 while(!len && s->pattern[s->pattern_pos]) {
247 len = s->pattern[s->pattern_pos] - '0';
248 s->pattern_pos++;
249 }
250
251 if (!s->pattern[s->pattern_pos])
252 s->pattern_pos = 0;
253
254 s->occupied = 0;
255 ++out;
256 }
257
258 if (s->occupied) {
259 for (i = 0; i < s->nb_planes; i++) {
260 // fill in the EARLIER field from the new pic
261 av_image_copy_plane(s->frame[out]->data[i] + s->frame[out]->linesize[i] * s->first_field,
262 s->frame[out]->linesize[i] * 2,
263 inpicref->data[i] + inpicref->linesize[i] * s->first_field,
264 inpicref->linesize[i] * 2,
265 s->stride[i],
266 (s->planeheight[i] - s->first_field + 1) / 2);
267 // fill in the LATER field from the buffered pic
268 av_image_copy_plane(s->frame[out]->data[i] + s->frame[out]->linesize[i] * !s->first_field,
269 s->frame[out]->linesize[i] * 2,
270 s->temp->data[i] + s->temp->linesize[i] * !s->first_field,
271 s->temp->linesize[i] * 2,
272 s->stride[i],
273 (s->planeheight[i] - !s->first_field + 1) / 2);
274 }
275
276 s->occupied = 0;
277 if (len <= 2) {
278 for (i = 0; i < s->nb_planes; i++) {
279 av_image_copy_plane(s->temp->data[i], s->temp->linesize[i],
280 inpicref->data[i], inpicref->linesize[i],
281 s->stride[i],
282 s->planeheight[i]);
283 }
284 s->occupied = 1;
285 }
286 ++out;
287 len = (len >= 3) ? len - 3 : 0;
288 } else {
289 if (len >= 2) {
290 // output THIS image as-is
291 for (i = 0; i < s->nb_planes; i++)
292 av_image_copy_plane(s->frame[out]->data[i], s->frame[out]->linesize[i],
293 inpicref->data[i], inpicref->linesize[i],
294 s->stride[i],
295 s->planeheight[i]);
296 len -= 2;
297 ++out;
298 } else if (len == 1) {
299 // output THIS image as-is
300 for (i = 0; i < s->nb_planes; i++)
301 av_image_copy_plane(s->frame[out]->data[i], s->frame[out]->linesize[i],
302 inpicref->data[i], inpicref->linesize[i],
303 s->stride[i],
304 s->planeheight[i]);
305
306 for (i = 0; i < s->nb_planes; i++) {
307 av_image_copy_plane(s->temp->data[i], s->temp->linesize[i],
308 inpicref->data[i], inpicref->linesize[i],
309 s->stride[i],
310 s->planeheight[i]);
311 }
312 s->occupied = 1;
313
314 len--;
315 ++out;
316 }
317 }
318
319 if (len == 1 && s->occupied)
320 {
321 len--;
322 s->occupied = 0;
323 }
324 }
325 s->nskip_fields = len;
326
327 for (i = 0; i < out; ++i) {
328 AVFrame *frame = av_frame_clone(s->frame[i]);
329
330 if (!frame) {
331 av_frame_free(&inpicref);
332 return AVERROR(ENOMEM);
333 }
334
335 av_frame_copy_props(frame, inpicref);
336 frame->pts = ((s->start_time == AV_NOPTS_VALUE) ? 0 : s->start_time) +
337 av_rescale(outlink->frame_count_in, s->ts_unit.num,
338 s->ts_unit.den);
339 ret = ff_filter_frame(outlink, frame);
340 }
341
342 av_frame_free(&inpicref);
343
344 return ret;
345 }
346
uninit(AVFilterContext * ctx)347 static av_cold void uninit(AVFilterContext *ctx)
348 {
349 DetelecineContext *s = ctx->priv;
350
351 av_frame_free(&s->temp);
352 av_frame_free(&s->frame[0]);
353 av_frame_free(&s->frame[1]);
354 }
355
356 static const AVFilterPad detelecine_inputs[] = {
357 {
358 .name = "default",
359 .type = AVMEDIA_TYPE_VIDEO,
360 .filter_frame = filter_frame,
361 .config_props = config_input,
362 },
363 { NULL }
364 };
365
366 static const AVFilterPad detelecine_outputs[] = {
367 {
368 .name = "default",
369 .type = AVMEDIA_TYPE_VIDEO,
370 .config_props = config_output,
371 },
372 { NULL }
373 };
374
375 AVFilter ff_vf_detelecine = {
376 .name = "detelecine",
377 .description = NULL_IF_CONFIG_SMALL("Apply an inverse telecine pattern."),
378 .priv_size = sizeof(DetelecineContext),
379 .priv_class = &detelecine_class,
380 .init = init,
381 .uninit = uninit,
382 .query_formats = query_formats,
383 .inputs = detelecine_inputs,
384 .outputs = detelecine_outputs,
385 };
386