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vf_scale.c
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1 /*
2  * Copyright (c) 2007 Bobby Bingham
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
23  * scale video filter
24  */
25 
26 #include <stdio.h>
27 #include <string.h>
28 
29 #include "avfilter.h"
30 #include "formats.h"
31 #include "internal.h"
32 #include "video.h"
33 #include "libavutil/avstring.h"
34 #include "libavutil/eval.h"
35 #include "libavutil/internal.h"
36 #include "libavutil/mathematics.h"
37 #include "libavutil/opt.h"
38 #include "libavutil/parseutils.h"
39 #include "libavutil/pixdesc.h"
40 #include "libavutil/imgutils.h"
41 #include "libavutil/avassert.h"
42 #include "libswscale/swscale.h"
43 
44 static const char *const var_names[] = {
45  "in_w", "iw",
46  "in_h", "ih",
47  "out_w", "ow",
48  "out_h", "oh",
49  "a",
50  "sar",
51  "dar",
52  "hsub",
53  "vsub",
54  NULL
55 };
56 
57 enum var_name {
58  VAR_IN_W, VAR_IW,
59  VAR_IN_H, VAR_IH,
60  VAR_OUT_W, VAR_OW,
61  VAR_OUT_H, VAR_OH,
62  VAR_A,
63  VAR_SAR,
64  VAR_DAR,
65  VAR_HSUB,
66  VAR_VSUB,
67  VARS_NB
68 };
69 
70 typedef struct {
71  const AVClass *class;
72  struct SwsContext *sws; ///< software scaler context
73  struct SwsContext *isws[2]; ///< software scaler context for interlaced material
74  AVDictionary *opts;
75 
76  /**
77  * New dimensions. Special values are:
78  * 0 = original width/height
79  * -1 = keep original aspect
80  */
81  int w, h;
82  char *size_str;
83  unsigned int flags; ///sws flags
84 
85  int hsub, vsub; ///< chroma subsampling
86  int slice_y; ///< top of current output slice
87  int input_is_pal; ///< set to 1 if the input format is paletted
88  int output_is_pal; ///< set to 1 if the output format is paletted
89  int interlaced;
90 
91  char *w_expr; ///< width expression string
92  char *h_expr; ///< height expression string
93  char *flags_str;
94 
95  char *in_color_matrix;
96  char *out_color_matrix;
97 
98  int in_range;
99  int out_range;
100 
101  int out_h_chr_pos;
102  int out_v_chr_pos;
103  int in_h_chr_pos;
104  int in_v_chr_pos;
105 
106  int force_original_aspect_ratio;
107 } ScaleContext;
108 
109 static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
110 {
111  ScaleContext *scale = ctx->priv;
112  int ret;
113 
114  if (scale->size_str && (scale->w_expr || scale->h_expr)) {
115  av_log(ctx, AV_LOG_ERROR,
116  "Size and width/height expressions cannot be set at the same time.\n");
117  return AVERROR(EINVAL);
118  }
119 
120  if (scale->w_expr && !scale->h_expr)
121  FFSWAP(char *, scale->w_expr, scale->size_str);
122 
123  if (scale->size_str) {
124  char buf[32];
125  if ((ret = av_parse_video_size(&scale->w, &scale->h, scale->size_str)) < 0) {
126  av_log(ctx, AV_LOG_ERROR,
127  "Invalid size '%s'\n", scale->size_str);
128  return ret;
129  }
130  snprintf(buf, sizeof(buf)-1, "%d", scale->w);
131  av_opt_set(scale, "w", buf, 0);
132  snprintf(buf, sizeof(buf)-1, "%d", scale->h);
133  av_opt_set(scale, "h", buf, 0);
134  }
135  if (!scale->w_expr)
136  av_opt_set(scale, "w", "iw", 0);
137  if (!scale->h_expr)
138  av_opt_set(scale, "h", "ih", 0);
139 
140  av_log(ctx, AV_LOG_VERBOSE, "w:%s h:%s flags:'%s' interl:%d\n",
141  scale->w_expr, scale->h_expr, (char *)av_x_if_null(scale->flags_str, ""), scale->interlaced);
142 
143  scale->flags = 0;
144 
145  if (scale->flags_str) {
146  const AVClass *class = sws_get_class();
147  const AVOption *o = av_opt_find(&class, "sws_flags", NULL, 0,
148  AV_OPT_SEARCH_FAKE_OBJ);
149  int ret = av_opt_eval_flags(&class, o, scale->flags_str, &scale->flags);
150  if (ret < 0)
151  return ret;
152  }
153  scale->opts = *opts;
154  *opts = NULL;
155 
156  return 0;
157 }
158 
159 static av_cold void uninit(AVFilterContext *ctx)
160 {
161  ScaleContext *scale = ctx->priv;
162  sws_freeContext(scale->sws);
163  sws_freeContext(scale->isws[0]);
164  sws_freeContext(scale->isws[1]);
165  scale->sws = NULL;
166  av_dict_free(&scale->opts);
167 }
168 
169 static int query_formats(AVFilterContext *ctx)
170 {
171  AVFilterFormats *formats;
172  enum AVPixelFormat pix_fmt;
173  int ret;
174 
175  if (ctx->inputs[0]) {
176  formats = NULL;
177  for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++)
178  if ((sws_isSupportedInput(pix_fmt) ||
179  sws_isSupportedEndiannessConversion(pix_fmt))
180  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
181  ff_formats_unref(&formats);
182  return ret;
183  }
184  ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
185  }
186  if (ctx->outputs[0]) {
187  formats = NULL;
188  for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++)
189  if ((sws_isSupportedOutput(pix_fmt) || pix_fmt == AV_PIX_FMT_PAL8 ||
190  sws_isSupportedEndiannessConversion(pix_fmt))
191  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
192  ff_formats_unref(&formats);
193  return ret;
194  }
195  ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
196  }
197 
198  return 0;
199 }
200 
201 static const int *parse_yuv_type(const char *s, enum AVColorSpace colorspace)
202 {
203  if (!s)
204  s = "bt601";
205 
206  if (s && strstr(s, "bt709")) {
207  colorspace = AVCOL_SPC_BT709;
208  } else if (s && strstr(s, "fcc")) {
209  colorspace = AVCOL_SPC_FCC;
210  } else if (s && strstr(s, "smpte240m")) {
211  colorspace = AVCOL_SPC_SMPTE240M;
212  } else if (s && (strstr(s, "bt601") || strstr(s, "bt470") || strstr(s, "smpte170m"))) {
213  colorspace = AVCOL_SPC_BT470BG;
214  }
215 
216  if (colorspace < 1 || colorspace > 7) {
217  colorspace = AVCOL_SPC_BT470BG;
218  }
219 
220  return sws_getCoefficients(colorspace);
221 }
222 
223 static int config_props(AVFilterLink *outlink)
224 {
225  AVFilterContext *ctx = outlink->src;
226  AVFilterLink *inlink = outlink->src->inputs[0];
227  enum AVPixelFormat outfmt = outlink->format;
228  ScaleContext *scale = ctx->priv;
229  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
230  int64_t w, h;
231  double var_values[VARS_NB], res;
232  char *expr;
233  int ret;
234 
235  var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
236  var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
237  var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
238  var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
239  var_values[VAR_A] = (double) inlink->w / inlink->h;
240  var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
241  (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
242  var_values[VAR_DAR] = var_values[VAR_A] * var_values[VAR_SAR];
243  var_values[VAR_HSUB] = 1 << desc->log2_chroma_w;
244  var_values[VAR_VSUB] = 1 << desc->log2_chroma_h;
245 
246  /* evaluate width and height */
247  av_expr_parse_and_eval(&res, (expr = scale->w_expr),
248  var_names, var_values,
249  NULL, NULL, NULL, NULL, NULL, 0, ctx);
250  scale->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
251  if ((ret = av_expr_parse_and_eval(&res, (expr = scale->h_expr),
252  var_names, var_values,
253  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
254  goto fail;
255  scale->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
256  /* evaluate again the width, as it may depend on the output height */
257  if ((ret = av_expr_parse_and_eval(&res, (expr = scale->w_expr),
258  var_names, var_values,
259  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
260  goto fail;
261  scale->w = res;
262 
263  w = scale->w;
264  h = scale->h;
265 
266  /* sanity check params */
267  if (w < -1 || h < -1) {
268  av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
269  return AVERROR(EINVAL);
270  }
271  if (w == -1 && h == -1)
272  scale->w = scale->h = 0;
273 
274  if (!(w = scale->w))
275  w = inlink->w;
276  if (!(h = scale->h))
277  h = inlink->h;
278  if (w == -1)
279  w = av_rescale(h, inlink->w, inlink->h);
280  if (h == -1)
281  h = av_rescale(w, inlink->h, inlink->w);
282 
283  if (scale->force_original_aspect_ratio) {
284  int tmp_w = av_rescale(h, inlink->w, inlink->h);
285  int tmp_h = av_rescale(w, inlink->h, inlink->w);
286 
287  if (scale->force_original_aspect_ratio == 1) {
288  w = FFMIN(tmp_w, w);
289  h = FFMIN(tmp_h, h);
290  } else {
291  w = FFMAX(tmp_w, w);
292  h = FFMAX(tmp_h, h);
293  }
294  }
295 
296  if (w > INT_MAX || h > INT_MAX ||
297  (h * inlink->w) > INT_MAX ||
298  (w * inlink->h) > INT_MAX)
299  av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
300 
301  outlink->w = w;
302  outlink->h = h;
303 
304  /* TODO: make algorithm configurable */
305 
306  scale->input_is_pal = desc->flags & AV_PIX_FMT_FLAG_PAL ||
307  desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL;
308  if (outfmt == AV_PIX_FMT_PAL8) outfmt = AV_PIX_FMT_BGR8;
309  scale->output_is_pal = av_pix_fmt_desc_get(outfmt)->flags & AV_PIX_FMT_FLAG_PAL ||
310  av_pix_fmt_desc_get(outfmt)->flags & AV_PIX_FMT_FLAG_PSEUDOPAL;
311 
312  if (scale->sws)
313  sws_freeContext(scale->sws);
314  if (scale->isws[0])
315  sws_freeContext(scale->isws[0]);
316  if (scale->isws[1])
317  sws_freeContext(scale->isws[1]);
318  scale->isws[0] = scale->isws[1] = scale->sws = NULL;
319  if (inlink->w == outlink->w && inlink->h == outlink->h &&
320  inlink->format == outlink->format)
321  ;
322  else {
323  struct SwsContext **swscs[3] = {&scale->sws, &scale->isws[0], &scale->isws[1]};
324  int i;
325 
326  for (i = 0; i < 3; i++) {
327  struct SwsContext **s = swscs[i];
328  *s = sws_alloc_context();
329  if (!*s)
330  return AVERROR(ENOMEM);
331 
332  if (scale->opts) {
333  AVDictionaryEntry *e = NULL;
334 
335  while ((e = av_dict_get(scale->opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
336  if ((ret = av_opt_set(*s, e->key, e->value, 0)) < 0)
337  return ret;
338  }
339  }
340 
341  av_opt_set_int(*s, "srcw", inlink ->w, 0);
342  av_opt_set_int(*s, "srch", inlink ->h >> !!i, 0);
343  av_opt_set_int(*s, "src_format", inlink->format, 0);
344  av_opt_set_int(*s, "dstw", outlink->w, 0);
345  av_opt_set_int(*s, "dsth", outlink->h >> !!i, 0);
346  av_opt_set_int(*s, "dst_format", outfmt, 0);
347  av_opt_set_int(*s, "sws_flags", scale->flags, 0);
348 
349  av_opt_set_int(*s, "src_h_chr_pos", scale->in_h_chr_pos, 0);
350  av_opt_set_int(*s, "src_v_chr_pos", scale->in_v_chr_pos, 0);
351  av_opt_set_int(*s, "dst_h_chr_pos", scale->out_h_chr_pos, 0);
352  av_opt_set_int(*s, "dst_v_chr_pos", scale->out_v_chr_pos, 0);
353 
354  if ((ret = sws_init_context(*s, NULL, NULL)) < 0)
355  return ret;
356  if (!scale->interlaced)
357  break;
358  }
359  }
360 
361  if (inlink->sample_aspect_ratio.num){
362  outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h * inlink->w, outlink->w * inlink->h}, inlink->sample_aspect_ratio);
363  } else
364  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
365 
366  av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s sar:%d/%d -> w:%d h:%d fmt:%s sar:%d/%d flags:0x%0x\n",
367  inlink ->w, inlink ->h, av_get_pix_fmt_name( inlink->format),
368  inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den,
369  outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
370  outlink->sample_aspect_ratio.num, outlink->sample_aspect_ratio.den,
371  scale->flags);
372  return 0;
373 
374 fail:
375  av_log(NULL, AV_LOG_ERROR,
376  "Error when evaluating the expression '%s'.\n"
377  "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
378  expr, scale->w_expr, scale->h_expr);
379  return ret;
380 }
381 
382 static int scale_slice(AVFilterLink *link, AVFrame *out_buf, AVFrame *cur_pic, struct SwsContext *sws, int y, int h, int mul, int field)
383 {
384  ScaleContext *scale = link->dst->priv;
385  const uint8_t *in[4];
386  uint8_t *out[4];
387  int in_stride[4],out_stride[4];
388  int i;
389 
390  for(i=0; i<4; i++){
391  int vsub= ((i+1)&2) ? scale->vsub : 0;
392  in_stride[i] = cur_pic->linesize[i] * mul;
393  out_stride[i] = out_buf->linesize[i] * mul;
394  in[i] = cur_pic->data[i] + ((y>>vsub)+field) * cur_pic->linesize[i];
395  out[i] = out_buf->data[i] + field * out_buf->linesize[i];
396  }
397  if(scale->input_is_pal)
398  in[1] = cur_pic->data[1];
399  if(scale->output_is_pal)
400  out[1] = out_buf->data[1];
401 
402  return sws_scale(sws, in, in_stride, y/mul, h,
403  out,out_stride);
404 }
405 
406 static int filter_frame(AVFilterLink *link, AVFrame *in)
407 {
408  ScaleContext *scale = link->dst->priv;
409  AVFilterLink *outlink = link->dst->outputs[0];
410  AVFrame *out;
411  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
412  char buf[32];
413  int in_range;
414 
415  if( in->width != link->w
416  || in->height != link->h
417  || in->format != link->format) {
418  int ret;
419  snprintf(buf, sizeof(buf)-1, "%d", outlink->w);
420  av_opt_set(scale, "w", buf, 0);
421  snprintf(buf, sizeof(buf)-1, "%d", outlink->h);
422  av_opt_set(scale, "h", buf, 0);
423 
424  link->dst->inputs[0]->format = in->format;
425  link->dst->inputs[0]->w = in->width;
426  link->dst->inputs[0]->h = in->height;
427 
428  if ((ret = config_props(outlink)) < 0)
429  return ret;
430  }
431 
432  if (!scale->sws)
433  return ff_filter_frame(outlink, in);
434 
435  scale->hsub = desc->log2_chroma_w;
436  scale->vsub = desc->log2_chroma_h;
437 
438  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
439  if (!out) {
440  av_frame_free(&in);
441  return AVERROR(ENOMEM);
442  }
443 
444  av_frame_copy_props(out, in);
445  out->width = outlink->w;
446  out->height = outlink->h;
447 
448  if(scale->output_is_pal)
449  avpriv_set_systematic_pal2((uint32_t*)out->data[1], outlink->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : outlink->format);
450 
451  in_range = av_frame_get_color_range(in);
452 
453  if ( scale->in_color_matrix
454  || scale->out_color_matrix
455  || scale-> in_range != AVCOL_RANGE_UNSPECIFIED
456  || in_range != AVCOL_RANGE_UNSPECIFIED
457  || scale->out_range != AVCOL_RANGE_UNSPECIFIED) {
458  int in_full, out_full, brightness, contrast, saturation;
459  const int *inv_table, *table;
460 
461  sws_getColorspaceDetails(scale->sws, (int **)&inv_table, &in_full,
462  (int **)&table, &out_full,
463  &brightness, &contrast, &saturation);
464 
465  if (scale->in_color_matrix)
466  inv_table = parse_yuv_type(scale->in_color_matrix, av_frame_get_colorspace(in));
467  if (scale->out_color_matrix)
468  table = parse_yuv_type(scale->out_color_matrix, AVCOL_SPC_UNSPECIFIED);
469 
470  if (scale-> in_range != AVCOL_RANGE_UNSPECIFIED)
471  in_full = (scale-> in_range == AVCOL_RANGE_JPEG);
472  else if (in_range != AVCOL_RANGE_UNSPECIFIED)
473  in_full = (in_range == AVCOL_RANGE_JPEG);
474  if (scale->out_range != AVCOL_RANGE_UNSPECIFIED)
475  out_full = (scale->out_range == AVCOL_RANGE_JPEG);
476 
477  sws_setColorspaceDetails(scale->sws, inv_table, in_full,
478  table, out_full,
479  brightness, contrast, saturation);
480  if (scale->isws[0])
481  sws_setColorspaceDetails(scale->isws[0], inv_table, in_full,
482  table, out_full,
483  brightness, contrast, saturation);
484  if (scale->isws[1])
485  sws_setColorspaceDetails(scale->isws[1], inv_table, in_full,
486  table, out_full,
487  brightness, contrast, saturation);
488  }
489 
490  av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
491  (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
492  (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
493  INT_MAX);
494 
495  if(scale->interlaced>0 || (scale->interlaced<0 && in->interlaced_frame)){
496  scale_slice(link, out, in, scale->isws[0], 0, (link->h+1)/2, 2, 0);
497  scale_slice(link, out, in, scale->isws[1], 0, link->h /2, 2, 1);
498  }else{
499  scale_slice(link, out, in, scale->sws, 0, link->h, 1, 0);
500  }
501 
502  av_frame_free(&in);
503  return ff_filter_frame(outlink, out);
504 }
505 
506 static const AVClass *child_class_next(const AVClass *prev)
507 {
508  return prev ? NULL : sws_get_class();
509 }
510 
511 #define OFFSET(x) offsetof(ScaleContext, x)
512 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
513 
514 static const AVOption scale_options[] = {
515  { "w", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, .flags = FLAGS },
516  { "width", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, .flags = FLAGS },
517  { "h", "Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, .flags = FLAGS },
518  { "height","Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, .flags = FLAGS },
519  { "flags", "Flags to pass to libswscale", OFFSET(flags_str), AV_OPT_TYPE_STRING, { .str = "bilinear" }, .flags = FLAGS },
520  { "interl", "set interlacing", OFFSET(interlaced), AV_OPT_TYPE_INT, {.i64 = 0 }, -1, 1, FLAGS },
521  { "size", "set video size", OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
522  { "s", "set video size", OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
523  { "in_color_matrix", "set input YCbCr type", OFFSET(in_color_matrix), AV_OPT_TYPE_STRING, { .str = "auto" }, .flags = FLAGS },
524  { "out_color_matrix", "set output YCbCr type", OFFSET(out_color_matrix), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = FLAGS },
525  { "in_range", "set input color range", OFFSET( in_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
526  { "out_range", "set output color range", OFFSET(out_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
527  { "auto", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 0, FLAGS, "range" },
528  { "full", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
529  { "jpeg", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
530  { "mpeg", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
531  { "tv", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
532  { "pc", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
533  { "in_v_chr_pos", "input vertical chroma position in luma grid/256" , OFFSET(in_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1}, -1, 512, FLAGS },
534  { "in_h_chr_pos", "input horizontal chroma position in luma grid/256", OFFSET(in_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1}, -1, 512, FLAGS },
535  { "out_v_chr_pos", "output vertical chroma position in luma grid/256" , OFFSET(out_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1}, -1, 512, FLAGS },
536  { "out_h_chr_pos", "output horizontal chroma position in luma grid/256", OFFSET(out_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1}, -1, 512, FLAGS },
537  { "force_original_aspect_ratio", "decrease or increase w/h if necessary to keep the original AR", OFFSET(force_original_aspect_ratio), AV_OPT_TYPE_INT, { .i64 = 0}, 0, 2, FLAGS, "force_oar" },
538  { "disable", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0 }, 0, 0, FLAGS, "force_oar" },
539  { "decrease", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, FLAGS, "force_oar" },
540  { "increase", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2 }, 0, 0, FLAGS, "force_oar" },
541  { NULL }
542 };
543 
544 static const AVClass scale_class = {
545  .class_name = "scale",
546  .item_name = av_default_item_name,
547  .option = scale_options,
548  .version = LIBAVUTIL_VERSION_INT,
549  .child_class_next = child_class_next,
550 };
551 
552 static const AVFilterPad avfilter_vf_scale_inputs[] = {
553  {
554  .name = "default",
555  .type = AVMEDIA_TYPE_VIDEO,
556  .filter_frame = filter_frame,
557  },
558  { NULL }
559 };
560 
561 static const AVFilterPad avfilter_vf_scale_outputs[] = {
562  {
563  .name = "default",
564  .type = AVMEDIA_TYPE_VIDEO,
565  .config_props = config_props,
566  },
567  { NULL }
568 };
569 
570 AVFilter avfilter_vf_scale = {
571  .name = "scale",
572  .description = NULL_IF_CONFIG_SMALL("Scale the input video size and/or convert the image format."),
573  .init_dict = init_dict,
574  .uninit = uninit,
575  .query_formats = query_formats,
576  .priv_size = sizeof(ScaleContext),
577  .priv_class = &scale_class,
578  .inputs = avfilter_vf_scale_inputs,
579  .outputs = avfilter_vf_scale_outputs,
580 };
Generated on Sat Jan 25 2014 19:52:01 for FFmpeg by   doxygen 1.8.2