git.sesse.net Git - ffmpeg/blob - libavfilter/vf_estdif.c

   1 /*
   2  * Copyright (c) 2021 Paul B Mahol
   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 #include "libavutil/common.h"
  22 #include "libavutil/imgutils.h"
  23 #include "libavutil/opt.h"
  24 #include "libavutil/pixdesc.h"
  25 #include "avfilter.h"
  26 #include "formats.h"
  27 #include "internal.h"
  28 #include "video.h"
  29
  30 typedef struct ESTDIFContext {
  31     const AVClass *class;
  32
  33     int mode;             ///< 0 is frame, 1 is field
  34     int parity;           ///< frame field parity
  35     int deint;            ///< which frames to deinterlace
  36     int rslope;           ///< best edge slope search radius
  37     int redge;            ///< best edge match search radius
  38     int interp;           ///< type of interpolation
  39     int linesize[4];      ///< bytes of pixel data per line for each plane
  40     int planewidth[4];    ///< width of each plane
  41     int planeheight[4];   ///< height of each plane
  42     int field;            ///< which field are we on, 0 or 1
  43     int eof;
  44     int depth;
  45     int half;
  46     int nb_planes;
  47     int nb_threads;
  48     int64_t pts;
  49     AVFrame *prev;
  50
  51     void (*interpolate)(struct ESTDIFContext *s, uint8_t *dst,
  52                         const uint8_t *prev_line,  const uint8_t *next_line,
  53                         const uint8_t *prev2_line, const uint8_t *next2_line,
  54                         const uint8_t *prev3_line, const uint8_t *next3_line,
  55                         int x, int width, int rslope, int redge, unsigned half,
  56                         int depth, int *K);
  57
  58     unsigned (*mid_8[3])(const uint8_t *const prev,
  59                          const uint8_t *const next,
  60                          const uint8_t *const prev2,
  61                          const uint8_t *const next2,
  62                          const uint8_t *const prev3,
  63                          const uint8_t *const next3,
  64                          int end, int x, int k, int depth);
  65
  66     unsigned (*mid_16[3])(const uint16_t *const prev,
  67                           const uint16_t *const next,
  68                           const uint16_t *const prev2,
  69                           const uint16_t *const next2,
  70                           const uint16_t *const prev3,
  71                           const uint16_t *const next3,
  72                           int end, int x, int k, int depth);
  73 } ESTDIFContext;
  74
  75 #define MAX_R 15
  76 #define S     (MAX_R * 2 + 1)
  77
  78 #define OFFSET(x) offsetof(ESTDIFContext, x)
  79 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
  80 #define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, 0, 0, FLAGS, unit }
  81
  82 static const AVOption estdif_options[] = {
  83     { "mode", "specify the mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS, "mode" },
  84     CONST("frame", "send one frame for each frame", 0, "mode"),
  85     CONST("field", "send one frame for each field", 1, "mode"),
  86     { "parity", "specify the assumed picture field parity", OFFSET(parity), AV_OPT_TYPE_INT, {.i64=-1}, -1, 1, FLAGS, "parity" },
  87     CONST("tff",  "assume top field first",    0, "parity"),
  88     CONST("bff",  "assume bottom field first", 1, "parity"),
  89     CONST("auto", "auto detect parity",       -1, "parity"),
  90     { "deint",  "specify which frames to deinterlace", OFFSET(deint), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, "deint" },
  91     CONST("all",        "deinterlace all frames",                       0, "deint"),
  92     CONST("interlaced", "only deinterlace frames marked as interlaced", 1, "deint"),
  93     { "rslope", "specify the search radius for edge slope tracing", OFFSET(rslope), AV_OPT_TYPE_INT, {.i64=1}, 1, MAX_R, FLAGS, },
  94     { "redge",  "specify the search radius for best edge matching", OFFSET(redge),  AV_OPT_TYPE_INT, {.i64=2}, 0, MAX_R, FLAGS, },
  95     { "interp", "specify the type of interpolation",                OFFSET(interp), AV_OPT_TYPE_INT, {.i64=1}, 0, 2,     FLAGS, "interp" },
  96     CONST("2p", "two-point interpolation",  0, "interp"),
  97     CONST("4p", "four-point interpolation", 1, "interp"),
  98     CONST("6p", "six-point interpolation",  2, "interp"),
  99     { NULL }
 100 };
 101
 102 AVFILTER_DEFINE_CLASS(estdif);
 103
 104 static int query_formats(AVFilterContext *ctx)
 105 {
 106     static const enum AVPixelFormat pix_fmts[] = {
 107         AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
 108         AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
 109         AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
 110         AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
 111         AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
 112         AV_PIX_FMT_YUVJ411P,
 113         AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
 114         AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP,
 115         AV_PIX_FMT_GRAY8,
 116         AV_PIX_FMT_GRAY9, AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16,
 117         AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
 118         AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
 119         AV_PIX_FMT_YUV440P10,
 120         AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12,
 121         AV_PIX_FMT_YUV440P12,
 122         AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
 123         AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
 124         AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
 125         AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12, AV_PIX_FMT_YUVA444P16,
 126         AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA422P16,
 127         AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA420P16,
 128         AV_PIX_FMT_GBRAP10,   AV_PIX_FMT_GBRAP12,    AV_PIX_FMT_GBRAP16,
 129         AV_PIX_FMT_NONE
 130     };
 131
 132     AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
 133     if (!fmts_list)
 134         return AVERROR(ENOMEM);
 135     return ff_set_common_formats(ctx, fmts_list);
 136 }
 137
 138 static int config_output(AVFilterLink *outlink)
 139 {
 140     AVFilterContext *ctx = outlink->src;
 141     AVFilterLink *inlink = ctx->inputs[0];
 142
 143     outlink->time_base.num = inlink->time_base.num;
 144     outlink->time_base.den = inlink->time_base.den * 2;
 145     outlink->frame_rate.num = inlink->frame_rate.num * 2;
 146     outlink->frame_rate.den = inlink->frame_rate.den;
 147
 148     return 0;
 149 }
 150
 151 typedef struct ThreadData {
 152     AVFrame *out, *in;
 153 } ThreadData;
 154
 155 #define MIDL(type, ss)                                         \
 156 static unsigned midl_##ss(const type *const prev,              \
 157                           const type *const next,              \
 158                           int end, int x, int k)               \
 159 {                                                              \
 160     return (prev[av_clip(x + k, 0, end)] +                     \
 161             next[av_clip(x - k, 0, end)] + 1) >> 1;            \
 162 }
 163
 164 MIDL(uint8_t, 8)
 165 MIDL(uint16_t, 16)
 166
 167 #define MID2(type, ss)                                         \
 168 static unsigned mid2_##ss(const type *const prev,              \
 169                           const type *const next,              \
 170                           const type *const prev2,             \
 171                           const type *const next2,             \
 172                           const type *const prev3,             \
 173                           const type *const next3,             \
 174                           int end, int x, int k, int depth)    \
 175 {                                                              \
 176     return (prev[av_clip(x + k, 0, end)] +                     \
 177             next[av_clip(x - k, 0, end)] + 1) >> 1;            \
 178 }
 179
 180 MID2(uint8_t, 8)
 181 MID2(uint16_t, 16)
 182
 183 #define MID4(type, ss)                                         \
 184 static unsigned mid4_##ss(const type *const prev,              \
 185                           const type *const next,              \
 186                           const type *const prev2,             \
 187                           const type *const next2,             \
 188                           const type *const prev3,             \
 189                           const type *const next3,             \
 190                           int end, int x, int k, int depth)    \
 191 {                                                              \
 192     return av_clip_uintp2_c((                                  \
 193             9 * (prev[av_clip(x + k, 0, end)] +                \
 194                  next[av_clip(x - k, 0, end)]) -               \
 195             1 * (prev2[av_clip(x + k*3, 0, end)] +             \
 196                  next2[av_clip(x - k*3, 0, end)]) + 8) >> 4,   \
 197                  depth);                                       \
 198 }
 199
 200 MID4(uint8_t, 8)
 201 MID4(uint16_t, 16)
 202
 203 #define MID6(type, ss)                                         \
 204 static unsigned mid6_##ss(const type *const prev,              \
 205                           const type *const next,              \
 206                           const type *const prev2,             \
 207                           const type *const next2,             \
 208                           const type *const prev3,             \
 209                           const type *const next3,             \
 210                           int end, int x, int k, int depth)    \
 211 {                                                              \
 212     return av_clip_uintp2_c((                                  \
 213            20 * (prev[av_clip(x + k, 0, end)] +                \
 214                  next[av_clip(x - k, 0, end)]) -               \
 215             5 * (prev2[av_clip(x + k*3, 0, end)] +             \
 216                  next2[av_clip(x - k*3, 0, end)]) +            \
 217             1 * (prev3[av_clip(x + k*5, 0, end)] +             \
 218                  next3[av_clip(x - k*5, 0, end)]) + 16) >> 5,  \
 219                  depth);                                       \
 220 }
 221
 222 MID6(uint8_t, 8)
 223 MID6(uint16_t, 16)
 224
 225 #define DIFF(type, ss)                                         \
 226 static unsigned diff_##ss(const type *const prev,              \
 227                           const type *const next,              \
 228                           int end, int x, int k, int j)        \
 229 {                                                              \
 230     return FFABS(prev[av_clip(x + k + j, 0, end)] -            \
 231                  next[av_clip(x - k + j, 0, end)]);            \
 232 }
 233
 234 DIFF(uint8_t, 8)
 235 DIFF(uint16_t, 16)
 236
 237 #define COST(type, ss)                                         \
 238 static unsigned cost_##ss(const type *const prev,              \
 239                           const type *const next,              \
 240                           int end, int x, int k)               \
 241 {                                                              \
 242     const int m = midl_##ss(prev, next, end, x, k);            \
 243     const int p = prev[x];                                     \
 244     const int n = next[x];                                     \
 245                                                                \
 246     return FFABS(p - m) + FFABS(n - m);                        \
 247 }
 248
 249 COST(uint8_t, 8)
 250 COST(uint16_t, 16)
 251
 252 #define INTERPOLATE(type, atype, max, ss)                                      \
 253 static void interpolate_##ss(ESTDIFContext *s, uint8_t *ddst,                  \
 254                              const uint8_t *const pprev_line,                  \
 255                              const uint8_t *const nnext_line,                  \
 256                              const uint8_t *const pprev2_line,                 \
 257                              const uint8_t *const nnext2_line,                 \
 258                              const uint8_t *const pprev3_line,                 \
 259                              const uint8_t *const nnext3_line,                 \
 260                              int x, int width, int rslope,                     \
 261                              int redge, unsigned h, int depth,                 \
 262                              int *K)                                           \
 263 {                                                                              \
 264     type *dst = (type *)ddst;                                                  \
 265     const type *const prev_line = (const type *const)pprev_line;               \
 266     const type *const prev2_line = (const type *const)pprev2_line;             \
 267     const type *const prev3_line = (const type *const)pprev3_line;             \
 268     const type *const next_line = (const type *const)nnext_line;               \
 269     const type *const next2_line = (const type *const)nnext2_line;             \
 270     const type *const next3_line = (const type *const)nnext3_line;             \
 271     const int interp = s->interp;                                              \
 272     const int end = width - 1;                                                 \
 273     const atype f = redge + 2;                                                 \
 274     atype sd[S], sD[S], di = 0;                                                \
 275     atype dmin = max;                                                          \
 276     int k = *K;                                                                \
 277                                                                                \
 278     for (int i = -rslope; i <= rslope && abs(k) > rslope; i++) {               \
 279         atype sum = 0;                                                         \
 280                                                                                \
 281         for (int j = -redge; j <= redge; j++) {                                \
 282             sum += diff_##ss(prev_line,  next_line,  end, x, i, j);            \
 283             sum += diff_##ss(prev2_line, prev_line,  end, x, i, j);            \
 284             sum += diff_##ss(next_line,  next2_line, end, x, i, j);            \
 285         }                                                                      \
 286                                                                                \
 287         sD[i + rslope]  =     sum;                                             \
 288         sD[i + rslope] += f * cost_##ss(prev_line,  next_line,  end, x, i);    \
 289         sD[i + rslope] += h * abs(i);                                          \
 290                                                                                \
 291         dmin = FFMIN(sD[i + rslope], dmin);                                    \
 292     }                                                                          \
 293                                                                                \
 294     for (int i = -rslope; i <= rslope; i++) {                                  \
 295         atype sum = 0;                                                         \
 296                                                                                \
 297         for (int j = -redge; j <= redge; j++) {                                \
 298             sum += diff_##ss(prev_line,  next_line,  end, x, k + i, j);        \
 299             sum += diff_##ss(prev2_line, prev_line,  end, x, k + i, j);        \
 300             sum += diff_##ss(next_line,  next2_line, end, x, k + i, j);        \
 301         }                                                                      \
 302                                                                                \
 303         sd[i + rslope]  =     sum;                                             \
 304         sd[i + rslope] += f * cost_##ss(prev_line, next_line, end, x, k + i);  \
 305         sd[i + rslope] += h * abs(k + i);                                      \
 306                                                                                \
 307         dmin = FFMIN(sd[i + rslope], dmin);                                    \
 308     }                                                                          \
 309                                                                                \
 310     for (int i = -rslope; i <= rslope && abs(k) > rslope; i++) {               \
 311         if (dmin == sD[i + rslope]) {                                          \
 312             di = 1;                                                            \
 313             k = i;                                                             \
 314             break;                                                             \
 315         }                                                                      \
 316     }                                                                          \
 317                                                                                \
 318     for (int i = -rslope; i <= rslope && !di; i++) {                           \
 319         if (dmin == sd[i + rslope]) {                                          \
 320             k += i;                                                            \
 321             break;                                                             \
 322         }                                                                      \
 323     }                                                                          \
 324                                                                                \
 325     dst[x] = s->mid_##ss[interp](prev_line, next_line,                         \
 326                                  prev2_line, next2_line,                       \
 327                                  prev3_line, next3_line,                       \
 328                                  end, x, k, depth);                            \
 329                                                                                \
 330     *K = k;                                                                    \
 331 }
 332
 333 INTERPOLATE(uint8_t,  unsigned, UINT_MAX, 8)
 334 INTERPOLATE(uint16_t, uint64_t, UINT64_MAX, 16)
 335
 336 static int deinterlace_slice(AVFilterContext *ctx, void *arg,
 337                              int jobnr, int nb_jobs)
 338 {
 339     ESTDIFContext *s = ctx->priv;
 340     ThreadData *td = arg;
 341     AVFrame *out = td->out;
 342     AVFrame *in = td->in;
 343     const int rslope = s->rslope;
 344     const int redge = s->redge;
 345     const int half = s->half;
 346     const int depth = s->depth;
 347     const int interlaced = in->interlaced_frame;
 348     const int tff = (s->field == (s->parity == -1 ? interlaced ? in->top_field_first : 1 :
 349                                   s->parity ^ 1));
 350
 351     for (int plane = 0; plane < s->nb_planes; plane++) {
 352         const uint8_t *src_data = in->data[plane];
 353         uint8_t *dst_data = out->data[plane];
 354         const int linesize = s->linesize[plane];
 355         const int width = s->planewidth[plane];
 356         const int height = s->planeheight[plane];
 357         const int src_linesize = in->linesize[plane];
 358         const int dst_linesize = out->linesize[plane];
 359         const int start = (height * jobnr) / nb_jobs;
 360         const int end = (height * (jobnr+1)) / nb_jobs;
 361         const uint8_t *prev_line, *prev2_line, *next_line, *next2_line, *in_line;
 362         const uint8_t *prev3_line, *next3_line;
 363         uint8_t *out_line;
 364         int y_out;
 365
 366         y_out = start + (tff ^ (start & 1));
 367
 368         in_line  = src_data + (y_out * src_linesize);
 369         out_line = dst_data + (y_out * dst_linesize);
 370
 371         while (y_out < end) {
 372             memcpy(out_line, in_line, linesize);
 373             y_out += 2;
 374             in_line  += src_linesize * 2;
 375             out_line += dst_linesize * 2;
 376         }
 377
 378         y_out = start + ((!tff) ^ (start & 1));
 379         out_line = dst_data + (y_out * dst_linesize);
 380
 381         for (int y = y_out; y < end; y += 2) {
 382             int y_prev3_in = y - 5;
 383             int y_next3_in = y + 5;
 384             int y_prev2_in = y - 3;
 385             int y_next2_in = y + 3;
 386             int y_prev_in = y - 1;
 387             int y_next_in = y + 1;
 388             int k;
 389
 390             while (y_prev3_in < 0)
 391                 y_prev3_in += 2;
 392
 393             while (y_next3_in >= height)
 394                 y_next3_in -= 2;
 395
 396             while (y_prev2_in < 0)
 397                 y_prev2_in += 2;
 398
 399             while (y_next2_in >= height)
 400                 y_next2_in -= 2;
 401
 402             while (y_prev_in < 0)
 403                 y_prev_in += 2;
 404
 405             while (y_next_in >= height)
 406                 y_next_in -= 2;
 407
 408             prev3_line = src_data + (y_prev3_in * src_linesize);
 409             next3_line = src_data + (y_next3_in * src_linesize);
 410
 411             prev2_line = src_data + (y_prev2_in * src_linesize);
 412             next2_line = src_data + (y_next2_in * src_linesize);
 413
 414             prev_line = src_data + (y_prev_in * src_linesize);
 415             next_line = src_data + (y_next_in * src_linesize);
 416
 417             k = 0;
 418
 419             for (int x = 0; x < width; x++) {
 420                 s->interpolate(s, out_line,
 421                                prev_line, next_line,
 422                                prev2_line, next2_line,
 423                                prev3_line, next3_line,
 424                                x, width, rslope, redge, half, depth, &k);
 425             }
 426
 427             out_line += 2 * dst_linesize;
 428         }
 429     }
 430
 431     return 0;
 432 }
 433
 434 static int filter(AVFilterContext *ctx, int is_second, AVFrame *in)
 435 {
 436     ESTDIFContext *s = ctx->priv;
 437     AVFilterLink *outlink = ctx->outputs[0];
 438     AVFrame *out;
 439     ThreadData td;
 440
 441     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
 442     if (!out)
 443         return AVERROR(ENOMEM);
 444     av_frame_copy_props(out, in);
 445     out->interlaced_frame = 0;
 446     out->pts = s->pts;
 447
 448     td.out = out; td.in = in;
 449     ctx->internal->execute(ctx, deinterlace_slice, &td, NULL,
 450                            FFMIN(s->planeheight[1] / 2, s->nb_threads));
 451
 452     if (s->mode)
 453         s->field = !s->field;
 454
 455     return ff_filter_frame(outlink, out);
 456 }
 457
 458 static int config_input(AVFilterLink *inlink)
 459 {
 460     AVFilterContext *ctx = inlink->dst;
 461     ESTDIFContext *s = ctx->priv;
 462     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
 463     int ret;
 464
 465     if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
 466         return ret;
 467
 468     s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
 469     s->planeheight[0] = s->planeheight[3] = inlink->h;
 470     s->planewidth[1] = s->planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
 471     s->planewidth[0] = s->planewidth[3] = inlink->w;
 472
 473     if (inlink->h < 3) {
 474         av_log(ctx, AV_LOG_ERROR, "Video of less than 3 lines is not supported\n");
 475         return AVERROR(EINVAL);
 476     }
 477
 478     s->nb_planes = av_pix_fmt_count_planes(inlink->format);
 479     s->nb_threads = ff_filter_get_nb_threads(ctx);
 480     s->depth = desc->comp[0].depth;
 481     s->interpolate = s->depth <= 8 ? interpolate_8 : interpolate_16;
 482     s->mid_8[0] = mid2_8;
 483     s->mid_8[1] = mid4_8;
 484     s->mid_8[2] = mid6_8;
 485     s->mid_16[0] = mid2_16;
 486     s->mid_16[1] = mid4_16;
 487     s->mid_16[2] = mid6_16;
 488     s->half = 1 << (s->depth - 1);
 489
 490     return 0;
 491 }
 492  static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 493 {
 494     AVFilterContext *ctx = inlink->dst;
 495     ESTDIFContext *s = ctx->priv;
 496     int ret;
 497
 498     if (!s->prev) {
 499         s->prev = in;
 500         return 0;
 501     }
 502
 503     if ((s->deint && !in->interlaced_frame) || ctx->is_disabled) {
 504         s->prev->pts *= 2;
 505         ret = ff_filter_frame(ctx->outputs[0], s->prev);
 506         s->prev = in;
 507         return ret;
 508     }
 509
 510     s->pts = s->prev->pts * 2;
 511     ret = filter(ctx, 0, s->prev);
 512     if (ret < 0 || s->mode == 0) {
 513         av_frame_free(&s->prev);
 514         s->prev = in;
 515         return ret;
 516     }
 517
 518     s->pts = s->prev->pts + in->pts;
 519     ret = filter(ctx, 1, s->prev);
 520     av_frame_free(&s->prev);
 521     s->prev = in;
 522     return ret;
 523 }
 524
 525 static int request_frame(AVFilterLink *link)
 526 {
 527     AVFilterContext *ctx = link->src;
 528     ESTDIFContext *s = ctx->priv;
 529     int ret;
 530
 531     if (s->eof)
 532         return AVERROR_EOF;
 533
 534     ret = ff_request_frame(ctx->inputs[0]);
 535
 536     if (ret == AVERROR_EOF && s->prev) {
 537         AVFrame *next = av_frame_clone(s->prev);
 538
 539         if (!next)
 540             return AVERROR(ENOMEM);
 541
 542         next->pts = s->prev->pts + av_rescale_q(1, av_inv_q(ctx->outputs[0]->frame_rate),
 543                                                 ctx->outputs[0]->time_base);
 544         s->eof = 1;
 545         ret = filter_frame(ctx->inputs[0], next);
 546     } else if (ret < 0) {
 547         return ret;
 548     }
 549
 550     return ret;
 551 }
 552
 553 static av_cold void uninit(AVFilterContext *ctx)
 554 {
 555     ESTDIFContext *s = ctx->priv;
 556
 557     av_frame_free(&s->prev);
 558 }
 559
 560 static const AVFilterPad estdif_inputs[] = {
 561     {
 562         .name          = "default",
 563         .type          = AVMEDIA_TYPE_VIDEO,
 564         .filter_frame  = filter_frame,
 565         .config_props  = config_input,
 566     },
 567     { NULL }
 568 };
 569
 570 static const AVFilterPad estdif_outputs[] = {
 571     {
 572         .name          = "default",
 573         .type          = AVMEDIA_TYPE_VIDEO,
 574         .config_props  = config_output,
 575         .request_frame = request_frame,
 576     },
 577     { NULL }
 578 };
 579
 580 const AVFilter ff_vf_estdif = {
 581     .name          = "estdif",
 582     .description   = NULL_IF_CONFIG_SMALL("Apply Edge Slope Tracing deinterlace."),
 583     .priv_size     = sizeof(ESTDIFContext),
 584     .priv_class    = &estdif_class,
 585     .uninit        = uninit,
 586     .query_formats = query_formats,
 587     .inputs        = estdif_inputs,
 588     .outputs       = estdif_outputs,
 589     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL | AVFILTER_FLAG_SLICE_THREADS,
 590     .process_command = ff_filter_process_command,
 591 };