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 "scale_eval.h"
33 #include "video.h"
34 #include "libavutil/avstring.h"
35 #include "libavutil/eval.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/mathematics.h"
38 #include "libavutil/opt.h"
39 #include "libavutil/parseutils.h"
40 #include "libavutil/pixdesc.h"
41 #include "libavutil/imgutils.h"
42 #include "libavutil/avassert.h"
43 #include "libswscale/swscale.h"
44 
45 static const char *const var_names[] = {
46     "in_w",   "iw",
47     "in_h",   "ih",
48     "out_w",  "ow",
49     "out_h",  "oh",
50     "a",
51     "sar",
52     "dar",
53     "hsub",
54     "vsub",
55     "ohsub",
56     "ovsub",
57     "n",
58     "t",
59     "pos",
60     "main_w",
61     "main_h",
62     "main_a",
63     "main_sar",
64     "main_dar", "mdar",
65     "main_hsub",
66     "main_vsub",
67     "main_n",
68     "main_t",
69     "main_pos",
70     NULL
71 };
72 
73 enum var_name {
74     VAR_IN_W,   VAR_IW,
75     VAR_IN_H,   VAR_IH,
76     VAR_OUT_W,  VAR_OW,
77     VAR_OUT_H,  VAR_OH,
78     VAR_A,
79     VAR_SAR,
80     VAR_DAR,
81     VAR_HSUB,
82     VAR_VSUB,
83     VAR_OHSUB,
84     VAR_OVSUB,
85     VAR_N,
86     VAR_T,
87     VAR_POS,
88     VAR_S2R_MAIN_W,
89     VAR_S2R_MAIN_H,
90     VAR_S2R_MAIN_A,
91     VAR_S2R_MAIN_SAR,
92     VAR_S2R_MAIN_DAR, VAR_S2R_MDAR,
93     VAR_S2R_MAIN_HSUB,
94     VAR_S2R_MAIN_VSUB,
95     VAR_S2R_MAIN_N,
96     VAR_S2R_MAIN_T,
97     VAR_S2R_MAIN_POS,
98     VARS_NB
99 };
100 
101 enum EvalMode {
102     EVAL_MODE_INIT,
103     EVAL_MODE_FRAME,
104     EVAL_MODE_NB
105 };
106 
107 typedef struct ScaleContext {
108     const AVClass *class;
109     struct SwsContext *sws;     ///< software scaler context
110     struct SwsContext *isws[2]; ///< software scaler context for interlaced material
111     AVDictionary *opts;
112 
113     /**
114      * New dimensions. Special values are:
115      *   0 = original width/height
116      *  -1 = keep original aspect
117      *  -N = try to keep aspect but make sure it is divisible by N
118      */
119     int w, h;
120     char *size_str;
121     unsigned int flags;         ///sws flags
122     double param[2];            // sws params
123 
124     int hsub, vsub;             ///< chroma subsampling
125     int slice_y;                ///< top of current output slice
126     int input_is_pal;           ///< set to 1 if the input format is paletted
127     int output_is_pal;          ///< set to 1 if the output format is paletted
128     int interlaced;
129 
130     char *w_expr;               ///< width  expression string
131     char *h_expr;               ///< height expression string
132     AVExpr *w_pexpr;
133     AVExpr *h_pexpr;
134     double var_values[VARS_NB];
135 
136     char *flags_str;
137 
138     char *in_color_matrix;
139     char *out_color_matrix;
140 
141     int in_range;
142     int out_range;
143 
144     int out_h_chr_pos;
145     int out_v_chr_pos;
146     int in_h_chr_pos;
147     int in_v_chr_pos;
148 
149     int force_original_aspect_ratio;
150     int force_divisible_by;
151 
152     int nb_slices;
153 
154     int eval_mode;              ///< expression evaluation mode
155 
156 } ScaleContext;
157 
158 AVFilter ff_vf_scale2ref;
159 
160 static int config_props(AVFilterLink *outlink);
161 
check_exprs(AVFilterContext * ctx)162 static int check_exprs(AVFilterContext *ctx)
163 {
164     ScaleContext *scale = ctx->priv;
165     unsigned vars_w[VARS_NB] = { 0 }, vars_h[VARS_NB] = { 0 };
166 
167     if (!scale->w_pexpr && !scale->h_pexpr)
168         return AVERROR(EINVAL);
169 
170     if (scale->w_pexpr)
171         av_expr_count_vars(scale->w_pexpr, vars_w, VARS_NB);
172     if (scale->h_pexpr)
173         av_expr_count_vars(scale->h_pexpr, vars_h, VARS_NB);
174 
175     if (vars_w[VAR_OUT_W] || vars_w[VAR_OW]) {
176         av_log(ctx, AV_LOG_ERROR, "Width expression cannot be self-referencing: '%s'.\n", scale->w_expr);
177         return AVERROR(EINVAL);
178     }
179 
180     if (vars_h[VAR_OUT_H] || vars_h[VAR_OH]) {
181         av_log(ctx, AV_LOG_ERROR, "Height expression cannot be self-referencing: '%s'.\n", scale->h_expr);
182         return AVERROR(EINVAL);
183     }
184 
185     if ((vars_w[VAR_OUT_H] || vars_w[VAR_OH]) &&
186         (vars_h[VAR_OUT_W] || vars_h[VAR_OW])) {
187         av_log(ctx, AV_LOG_WARNING, "Circular references detected for width '%s' and height '%s' - possibly invalid.\n", scale->w_expr, scale->h_expr);
188     }
189 
190     if (ctx->filter != &ff_vf_scale2ref &&
191         (vars_w[VAR_S2R_MAIN_W]    || vars_h[VAR_S2R_MAIN_W]    ||
192          vars_w[VAR_S2R_MAIN_H]    || vars_h[VAR_S2R_MAIN_H]    ||
193          vars_w[VAR_S2R_MAIN_A]    || vars_h[VAR_S2R_MAIN_A]    ||
194          vars_w[VAR_S2R_MAIN_SAR]  || vars_h[VAR_S2R_MAIN_SAR]  ||
195          vars_w[VAR_S2R_MAIN_DAR]  || vars_h[VAR_S2R_MAIN_DAR]  ||
196          vars_w[VAR_S2R_MDAR]      || vars_h[VAR_S2R_MDAR]      ||
197          vars_w[VAR_S2R_MAIN_HSUB] || vars_h[VAR_S2R_MAIN_HSUB] ||
198          vars_w[VAR_S2R_MAIN_VSUB] || vars_h[VAR_S2R_MAIN_VSUB] ||
199          vars_w[VAR_S2R_MAIN_N]    || vars_h[VAR_S2R_MAIN_N]    ||
200          vars_w[VAR_S2R_MAIN_T]    || vars_h[VAR_S2R_MAIN_T]    ||
201          vars_w[VAR_S2R_MAIN_POS]  || vars_h[VAR_S2R_MAIN_POS]) ) {
202         av_log(ctx, AV_LOG_ERROR, "Expressions with scale2ref variables are not valid in scale filter.\n");
203         return AVERROR(EINVAL);
204     }
205 
206     if (scale->eval_mode == EVAL_MODE_INIT &&
207         (vars_w[VAR_N]            || vars_h[VAR_N]           ||
208          vars_w[VAR_T]            || vars_h[VAR_T]           ||
209          vars_w[VAR_POS]          || vars_h[VAR_POS]         ||
210          vars_w[VAR_S2R_MAIN_N]   || vars_h[VAR_S2R_MAIN_N]  ||
211          vars_w[VAR_S2R_MAIN_T]   || vars_h[VAR_S2R_MAIN_T]  ||
212          vars_w[VAR_S2R_MAIN_POS] || vars_h[VAR_S2R_MAIN_POS]) ) {
213         av_log(ctx, AV_LOG_ERROR, "Expressions with frame variables 'n', 't', 'pos' are not valid in init eval_mode.\n");
214         return AVERROR(EINVAL);
215     }
216 
217     return 0;
218 }
219 
scale_parse_expr(AVFilterContext * ctx,char * str_expr,AVExpr ** pexpr_ptr,const char * var,const char * args)220 static int scale_parse_expr(AVFilterContext *ctx, char *str_expr, AVExpr **pexpr_ptr, const char *var, const char *args)
221 {
222     ScaleContext *scale = ctx->priv;
223     int ret, is_inited = 0;
224     char *old_str_expr = NULL;
225     AVExpr *old_pexpr = NULL;
226 
227     if (str_expr) {
228         old_str_expr = av_strdup(str_expr);
229         if (!old_str_expr)
230             return AVERROR(ENOMEM);
231         av_opt_set(scale, var, args, 0);
232     }
233 
234     if (*pexpr_ptr) {
235         old_pexpr = *pexpr_ptr;
236         *pexpr_ptr = NULL;
237         is_inited = 1;
238     }
239 
240     ret = av_expr_parse(pexpr_ptr, args, var_names,
241                         NULL, NULL, NULL, NULL, 0, ctx);
242     if (ret < 0) {
243         av_log(ctx, AV_LOG_ERROR, "Cannot parse expression for %s: '%s'\n", var, args);
244         goto revert;
245     }
246 
247     ret = check_exprs(ctx);
248     if (ret < 0)
249         goto revert;
250 
251     if (is_inited && (ret = config_props(ctx->outputs[0])) < 0)
252         goto revert;
253 
254     av_expr_free(old_pexpr);
255     old_pexpr = NULL;
256     av_freep(&old_str_expr);
257 
258     return 0;
259 
260 revert:
261     av_expr_free(*pexpr_ptr);
262     *pexpr_ptr = NULL;
263     if (old_str_expr) {
264         av_opt_set(scale, var, old_str_expr, 0);
265         av_free(old_str_expr);
266     }
267     if (old_pexpr)
268         *pexpr_ptr = old_pexpr;
269 
270     return ret;
271 }
272 
init_dict(AVFilterContext * ctx,AVDictionary ** opts)273 static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
274 {
275     ScaleContext *scale = ctx->priv;
276     int ret;
277 
278     if (scale->size_str && (scale->w_expr || scale->h_expr)) {
279         av_log(ctx, AV_LOG_ERROR,
280                "Size and width/height expressions cannot be set at the same time.\n");
281             return AVERROR(EINVAL);
282     }
283 
284     if (scale->w_expr && !scale->h_expr)
285         FFSWAP(char *, scale->w_expr, scale->size_str);
286 
287     if (scale->size_str) {
288         char buf[32];
289         if ((ret = av_parse_video_size(&scale->w, &scale->h, scale->size_str)) < 0) {
290             av_log(ctx, AV_LOG_ERROR,
291                    "Invalid size '%s'\n", scale->size_str);
292             return ret;
293         }
294         snprintf(buf, sizeof(buf)-1, "%d", scale->w);
295         av_opt_set(scale, "w", buf, 0);
296         snprintf(buf, sizeof(buf)-1, "%d", scale->h);
297         av_opt_set(scale, "h", buf, 0);
298     }
299     if (!scale->w_expr)
300         av_opt_set(scale, "w", "iw", 0);
301     if (!scale->h_expr)
302         av_opt_set(scale, "h", "ih", 0);
303 
304     ret = scale_parse_expr(ctx, NULL, &scale->w_pexpr, "width", scale->w_expr);
305     if (ret < 0)
306         return ret;
307 
308     ret = scale_parse_expr(ctx, NULL, &scale->h_pexpr, "height", scale->h_expr);
309     if (ret < 0)
310         return ret;
311 
312     av_log(ctx, AV_LOG_VERBOSE, "w:%s h:%s flags:'%s' interl:%d\n",
313            scale->w_expr, scale->h_expr, (char *)av_x_if_null(scale->flags_str, ""), scale->interlaced);
314 
315     scale->flags = 0;
316 
317     if (scale->flags_str) {
318         const AVClass *class = sws_get_class();
319         const AVOption    *o = av_opt_find(&class, "sws_flags", NULL, 0,
320                                            AV_OPT_SEARCH_FAKE_OBJ);
321         int ret = av_opt_eval_flags(&class, o, scale->flags_str, &scale->flags);
322         if (ret < 0)
323             return ret;
324     }
325     scale->opts = *opts;
326     *opts = NULL;
327 
328     return 0;
329 }
330 
uninit(AVFilterContext * ctx)331 static av_cold void uninit(AVFilterContext *ctx)
332 {
333     ScaleContext *scale = ctx->priv;
334     av_expr_free(scale->w_pexpr);
335     av_expr_free(scale->h_pexpr);
336     scale->w_pexpr = scale->h_pexpr = NULL;
337     sws_freeContext(scale->sws);
338     sws_freeContext(scale->isws[0]);
339     sws_freeContext(scale->isws[1]);
340     scale->sws = NULL;
341     av_dict_free(&scale->opts);
342 }
343 
query_formats(AVFilterContext * ctx)344 static int query_formats(AVFilterContext *ctx)
345 {
346     AVFilterFormats *formats;
347     enum AVPixelFormat pix_fmt;
348     int ret;
349 
350     if (ctx->inputs[0]) {
351         const AVPixFmtDescriptor *desc = NULL;
352         formats = NULL;
353         while ((desc = av_pix_fmt_desc_next(desc))) {
354             pix_fmt = av_pix_fmt_desc_get_id(desc);
355             if ((sws_isSupportedInput(pix_fmt) ||
356                  sws_isSupportedEndiannessConversion(pix_fmt))
357                 && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
358                 return ret;
359             }
360         }
361         if ((ret = ff_formats_ref(formats, &ctx->inputs[0]->outcfg.formats)) < 0)
362             return ret;
363     }
364     if (ctx->outputs[0]) {
365         const AVPixFmtDescriptor *desc = NULL;
366         formats = NULL;
367         while ((desc = av_pix_fmt_desc_next(desc))) {
368             pix_fmt = av_pix_fmt_desc_get_id(desc);
369             if ((sws_isSupportedOutput(pix_fmt) || pix_fmt == AV_PIX_FMT_PAL8 ||
370                  sws_isSupportedEndiannessConversion(pix_fmt))
371                 && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
372                 return ret;
373             }
374         }
375         if ((ret = ff_formats_ref(formats, &ctx->outputs[0]->incfg.formats)) < 0)
376             return ret;
377     }
378 
379     return 0;
380 }
381 
parse_yuv_type(const char * s,enum AVColorSpace colorspace)382 static const int *parse_yuv_type(const char *s, enum AVColorSpace colorspace)
383 {
384     if (!s)
385         s = "bt601";
386 
387     if (s && strstr(s, "bt709")) {
388         colorspace = AVCOL_SPC_BT709;
389     } else if (s && strstr(s, "fcc")) {
390         colorspace = AVCOL_SPC_FCC;
391     } else if (s && strstr(s, "smpte240m")) {
392         colorspace = AVCOL_SPC_SMPTE240M;
393     } else if (s && (strstr(s, "bt601") || strstr(s, "bt470") || strstr(s, "smpte170m"))) {
394         colorspace = AVCOL_SPC_BT470BG;
395     } else if (s && strstr(s, "bt2020")) {
396         colorspace = AVCOL_SPC_BT2020_NCL;
397     }
398 
399     if (colorspace < 1 || colorspace > 10 || colorspace == 8) {
400         colorspace = AVCOL_SPC_BT470BG;
401     }
402 
403     return sws_getCoefficients(colorspace);
404 }
405 
scale_eval_dimensions(AVFilterContext * ctx)406 static int scale_eval_dimensions(AVFilterContext *ctx)
407 {
408     ScaleContext *scale = ctx->priv;
409     const char scale2ref = ctx->filter == &ff_vf_scale2ref;
410     const AVFilterLink *inlink = scale2ref ? ctx->inputs[1] : ctx->inputs[0];
411     const AVFilterLink *outlink = ctx->outputs[0];
412     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
413     const AVPixFmtDescriptor *out_desc = av_pix_fmt_desc_get(outlink->format);
414     char *expr;
415     int eval_w, eval_h;
416     int ret;
417     double res;
418     const AVPixFmtDescriptor *main_desc;
419     const AVFilterLink *main_link;
420 
421     if (scale2ref) {
422         main_link = ctx->inputs[0];
423         main_desc = av_pix_fmt_desc_get(main_link->format);
424     }
425 
426     scale->var_values[VAR_IN_W]  = scale->var_values[VAR_IW] = inlink->w;
427     scale->var_values[VAR_IN_H]  = scale->var_values[VAR_IH] = inlink->h;
428     scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = NAN;
429     scale->var_values[VAR_OUT_H] = scale->var_values[VAR_OH] = NAN;
430     scale->var_values[VAR_A]     = (double) inlink->w / inlink->h;
431     scale->var_values[VAR_SAR]   = inlink->sample_aspect_ratio.num ?
432         (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
433     scale->var_values[VAR_DAR]   = scale->var_values[VAR_A] * scale->var_values[VAR_SAR];
434     scale->var_values[VAR_HSUB]  = 1 << desc->log2_chroma_w;
435     scale->var_values[VAR_VSUB]  = 1 << desc->log2_chroma_h;
436     scale->var_values[VAR_OHSUB] = 1 << out_desc->log2_chroma_w;
437     scale->var_values[VAR_OVSUB] = 1 << out_desc->log2_chroma_h;
438 
439     if (scale2ref) {
440         scale->var_values[VAR_S2R_MAIN_W] = main_link->w;
441         scale->var_values[VAR_S2R_MAIN_H] = main_link->h;
442         scale->var_values[VAR_S2R_MAIN_A] = (double) main_link->w / main_link->h;
443         scale->var_values[VAR_S2R_MAIN_SAR] = main_link->sample_aspect_ratio.num ?
444             (double) main_link->sample_aspect_ratio.num / main_link->sample_aspect_ratio.den : 1;
445         scale->var_values[VAR_S2R_MAIN_DAR] = scale->var_values[VAR_S2R_MDAR] =
446             scale->var_values[VAR_S2R_MAIN_A] * scale->var_values[VAR_S2R_MAIN_SAR];
447         scale->var_values[VAR_S2R_MAIN_HSUB] = 1 << main_desc->log2_chroma_w;
448         scale->var_values[VAR_S2R_MAIN_VSUB] = 1 << main_desc->log2_chroma_h;
449     }
450 
451     res = av_expr_eval(scale->w_pexpr, scale->var_values, NULL);
452     eval_w = scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = (int) res == 0 ? inlink->w : (int) res;
453 
454     res = av_expr_eval(scale->h_pexpr, scale->var_values, NULL);
455     if (isnan(res)) {
456         expr = scale->h_expr;
457         ret = AVERROR(EINVAL);
458         goto fail;
459     }
460     eval_h = scale->var_values[VAR_OUT_H] = scale->var_values[VAR_OH] = (int) res == 0 ? inlink->h : (int) res;
461 
462     res = av_expr_eval(scale->w_pexpr, scale->var_values, NULL);
463     if (isnan(res)) {
464         expr = scale->w_expr;
465         ret = AVERROR(EINVAL);
466         goto fail;
467     }
468     eval_w = scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = (int) res == 0 ? inlink->w : (int) res;
469 
470     scale->w = eval_w;
471     scale->h = eval_h;
472 
473     return 0;
474 
475 fail:
476     av_log(ctx, AV_LOG_ERROR,
477            "Error when evaluating the expression '%s'.\n", expr);
478     return ret;
479 }
480 
config_props(AVFilterLink * outlink)481 static int config_props(AVFilterLink *outlink)
482 {
483     AVFilterContext *ctx = outlink->src;
484     AVFilterLink *inlink0 = outlink->src->inputs[0];
485     AVFilterLink *inlink  = ctx->filter == &ff_vf_scale2ref ?
486                             outlink->src->inputs[1] :
487                             outlink->src->inputs[0];
488     enum AVPixelFormat outfmt = outlink->format;
489     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
490     ScaleContext *scale = ctx->priv;
491     int ret;
492 
493     if ((ret = scale_eval_dimensions(ctx)) < 0)
494         goto fail;
495 
496     ff_scale_adjust_dimensions(inlink, &scale->w, &scale->h,
497                                scale->force_original_aspect_ratio,
498                                scale->force_divisible_by);
499 
500     if (scale->w > INT_MAX ||
501         scale->h > INT_MAX ||
502         (scale->h * inlink->w) > INT_MAX ||
503         (scale->w * inlink->h) > INT_MAX)
504         av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
505 
506     outlink->w = scale->w;
507     outlink->h = scale->h;
508 
509     /* TODO: make algorithm configurable */
510 
511     scale->input_is_pal = desc->flags & AV_PIX_FMT_FLAG_PAL;
512     if (outfmt == AV_PIX_FMT_PAL8) outfmt = AV_PIX_FMT_BGR8;
513     scale->output_is_pal = av_pix_fmt_desc_get(outfmt)->flags & AV_PIX_FMT_FLAG_PAL ||
514                            av_pix_fmt_desc_get(outfmt)->flags & FF_PSEUDOPAL;
515 
516     if (scale->sws)
517         sws_freeContext(scale->sws);
518     if (scale->isws[0])
519         sws_freeContext(scale->isws[0]);
520     if (scale->isws[1])
521         sws_freeContext(scale->isws[1]);
522     scale->isws[0] = scale->isws[1] = scale->sws = NULL;
523     if (inlink0->w == outlink->w &&
524         inlink0->h == outlink->h &&
525         !scale->out_color_matrix &&
526         scale->in_range == scale->out_range &&
527         inlink0->format == outlink->format)
528         ;
529     else {
530         struct SwsContext **swscs[3] = {&scale->sws, &scale->isws[0], &scale->isws[1]};
531         int i;
532 
533         for (i = 0; i < 3; i++) {
534             int in_v_chr_pos = scale->in_v_chr_pos, out_v_chr_pos = scale->out_v_chr_pos;
535             struct SwsContext **s = swscs[i];
536             *s = sws_alloc_context();
537             if (!*s)
538                 return AVERROR(ENOMEM);
539 
540             av_opt_set_int(*s, "srcw", inlink0 ->w, 0);
541             av_opt_set_int(*s, "srch", inlink0 ->h >> !!i, 0);
542             av_opt_set_int(*s, "src_format", inlink0->format, 0);
543             av_opt_set_int(*s, "dstw", outlink->w, 0);
544             av_opt_set_int(*s, "dsth", outlink->h >> !!i, 0);
545             av_opt_set_int(*s, "dst_format", outfmt, 0);
546             av_opt_set_int(*s, "sws_flags", scale->flags, 0);
547             av_opt_set_int(*s, "param0", scale->param[0], 0);
548             av_opt_set_int(*s, "param1", scale->param[1], 0);
549             if (scale->in_range != AVCOL_RANGE_UNSPECIFIED)
550                 av_opt_set_int(*s, "src_range",
551                                scale->in_range == AVCOL_RANGE_JPEG, 0);
552             if (scale->out_range != AVCOL_RANGE_UNSPECIFIED)
553                 av_opt_set_int(*s, "dst_range",
554                                scale->out_range == AVCOL_RANGE_JPEG, 0);
555 
556             if (scale->opts) {
557                 AVDictionaryEntry *e = NULL;
558                 while ((e = av_dict_get(scale->opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
559                     if ((ret = av_opt_set(*s, e->key, e->value, 0)) < 0)
560                         return ret;
561                 }
562             }
563             /* Override YUV420P default settings to have the correct (MPEG-2) chroma positions
564              * MPEG-2 chroma positions are used by convention
565              * XXX: support other 4:2:0 pixel formats */
566             if (inlink0->format == AV_PIX_FMT_YUV420P && scale->in_v_chr_pos == -513) {
567                 in_v_chr_pos = (i == 0) ? 128 : (i == 1) ? 64 : 192;
568             }
569 
570             if (outlink->format == AV_PIX_FMT_YUV420P && scale->out_v_chr_pos == -513) {
571                 out_v_chr_pos = (i == 0) ? 128 : (i == 1) ? 64 : 192;
572             }
573 
574             av_opt_set_int(*s, "src_h_chr_pos", scale->in_h_chr_pos, 0);
575             av_opt_set_int(*s, "src_v_chr_pos", in_v_chr_pos, 0);
576             av_opt_set_int(*s, "dst_h_chr_pos", scale->out_h_chr_pos, 0);
577             av_opt_set_int(*s, "dst_v_chr_pos", out_v_chr_pos, 0);
578 
579             if ((ret = sws_init_context(*s, NULL, NULL)) < 0)
580                 return ret;
581             if (!scale->interlaced)
582                 break;
583         }
584     }
585 
586     if (inlink0->sample_aspect_ratio.num){
587         outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h * inlink0->w, outlink->w * inlink0->h}, inlink0->sample_aspect_ratio);
588     } else
589         outlink->sample_aspect_ratio = inlink0->sample_aspect_ratio;
590 
591     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",
592            inlink ->w, inlink ->h, av_get_pix_fmt_name( inlink->format),
593            inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den,
594            outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
595            outlink->sample_aspect_ratio.num, outlink->sample_aspect_ratio.den,
596            scale->flags);
597     return 0;
598 
599 fail:
600     return ret;
601 }
602 
config_props_ref(AVFilterLink * outlink)603 static int config_props_ref(AVFilterLink *outlink)
604 {
605     AVFilterLink *inlink = outlink->src->inputs[1];
606 
607     outlink->w = inlink->w;
608     outlink->h = inlink->h;
609     outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
610     outlink->time_base = inlink->time_base;
611     outlink->frame_rate = inlink->frame_rate;
612 
613     return 0;
614 }
615 
request_frame(AVFilterLink * outlink)616 static int request_frame(AVFilterLink *outlink)
617 {
618     return ff_request_frame(outlink->src->inputs[0]);
619 }
620 
request_frame_ref(AVFilterLink * outlink)621 static int request_frame_ref(AVFilterLink *outlink)
622 {
623     return ff_request_frame(outlink->src->inputs[1]);
624 }
625 
scale_slice(AVFilterLink * link,AVFrame * out_buf,AVFrame * cur_pic,struct SwsContext * sws,int y,int h,int mul,int field)626 static int scale_slice(AVFilterLink *link, AVFrame *out_buf, AVFrame *cur_pic, struct SwsContext *sws, int y, int h, int mul, int field)
627 {
628     ScaleContext *scale = link->dst->priv;
629     const uint8_t *in[4];
630     uint8_t *out[4];
631     int in_stride[4],out_stride[4];
632     int i;
633 
634     for (i=0; i<4; i++) {
635         int vsub= ((i+1)&2) ? scale->vsub : 0;
636          in_stride[i] = cur_pic->linesize[i] * mul;
637         out_stride[i] = out_buf->linesize[i] * mul;
638          in[i] = FF_PTR_ADD(cur_pic->data[i], ((y>>vsub)+field) * cur_pic->linesize[i]);
639         out[i] = FF_PTR_ADD(out_buf->data[i],            field  * out_buf->linesize[i]);
640     }
641     if (scale->input_is_pal)
642          in[1] = cur_pic->data[1];
643     if (scale->output_is_pal)
644         out[1] = out_buf->data[1];
645 
646     return sws_scale(sws, in, in_stride, y/mul, h,
647                          out,out_stride);
648 }
649 
scale_frame(AVFilterLink * link,AVFrame * in,AVFrame ** frame_out)650 static int scale_frame(AVFilterLink *link, AVFrame *in, AVFrame **frame_out)
651 {
652     AVFilterContext *ctx = link->dst;
653     ScaleContext *scale = ctx->priv;
654     AVFilterLink *outlink = ctx->outputs[0];
655     AVFrame *out;
656     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
657     char buf[32];
658     int in_range;
659     int frame_changed;
660 
661     *frame_out = NULL;
662     if (in->colorspace == AVCOL_SPC_YCGCO)
663         av_log(link->dst, AV_LOG_WARNING, "Detected unsupported YCgCo colorspace.\n");
664 
665     frame_changed = in->width  != link->w ||
666                     in->height != link->h ||
667                     in->format != link->format ||
668                     in->sample_aspect_ratio.den != link->sample_aspect_ratio.den ||
669                     in->sample_aspect_ratio.num != link->sample_aspect_ratio.num;
670 
671     if (scale->eval_mode == EVAL_MODE_FRAME || frame_changed) {
672         int ret;
673         unsigned vars_w[VARS_NB] = { 0 }, vars_h[VARS_NB] = { 0 };
674 
675         av_expr_count_vars(scale->w_pexpr, vars_w, VARS_NB);
676         av_expr_count_vars(scale->h_pexpr, vars_h, VARS_NB);
677 
678         if (scale->eval_mode == EVAL_MODE_FRAME &&
679             !frame_changed &&
680             ctx->filter != &ff_vf_scale2ref &&
681             !(vars_w[VAR_N] || vars_w[VAR_T] || vars_w[VAR_POS]) &&
682             !(vars_h[VAR_N] || vars_h[VAR_T] || vars_h[VAR_POS]) &&
683             scale->w && scale->h)
684             goto scale;
685 
686         if (scale->eval_mode == EVAL_MODE_INIT) {
687             snprintf(buf, sizeof(buf)-1, "%d", outlink->w);
688             av_opt_set(scale, "w", buf, 0);
689             snprintf(buf, sizeof(buf)-1, "%d", outlink->h);
690             av_opt_set(scale, "h", buf, 0);
691 
692             ret = scale_parse_expr(ctx, NULL, &scale->w_pexpr, "width", scale->w_expr);
693             if (ret < 0)
694                 return ret;
695 
696             ret = scale_parse_expr(ctx, NULL, &scale->h_pexpr, "height", scale->h_expr);
697             if (ret < 0)
698                 return ret;
699         }
700 
701         if (ctx->filter == &ff_vf_scale2ref) {
702             scale->var_values[VAR_S2R_MAIN_N] = link->frame_count_out;
703             scale->var_values[VAR_S2R_MAIN_T] = TS2T(in->pts, link->time_base);
704             scale->var_values[VAR_S2R_MAIN_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
705         } else {
706             scale->var_values[VAR_N] = link->frame_count_out;
707             scale->var_values[VAR_T] = TS2T(in->pts, link->time_base);
708             scale->var_values[VAR_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
709         }
710 
711         link->dst->inputs[0]->format = in->format;
712         link->dst->inputs[0]->w      = in->width;
713         link->dst->inputs[0]->h      = in->height;
714 
715         link->dst->inputs[0]->sample_aspect_ratio.den = in->sample_aspect_ratio.den;
716         link->dst->inputs[0]->sample_aspect_ratio.num = in->sample_aspect_ratio.num;
717 
718         if ((ret = config_props(outlink)) < 0)
719             return ret;
720     }
721 
722 scale:
723     if (!scale->sws) {
724         *frame_out = in;
725         return 0;
726     }
727 
728     scale->hsub = desc->log2_chroma_w;
729     scale->vsub = desc->log2_chroma_h;
730 
731     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
732     if (!out) {
733         av_frame_free(&in);
734         return AVERROR(ENOMEM);
735     }
736     *frame_out = out;
737 
738     av_frame_copy_props(out, in);
739     out->width  = outlink->w;
740     out->height = outlink->h;
741 
742     // Sanity checks:
743     //   1. If the output is RGB, set the matrix coefficients to RGB.
744     //   2. If the output is not RGB and we've got the RGB/XYZ (identity)
745     //      matrix configured, unset the matrix.
746     //   In theory these should be in swscale itself as the AVFrame
747     //   based API gets in, so that not every swscale API user has
748     //   to go through duplicating such sanity checks.
749     if (av_pix_fmt_desc_get(out->format)->flags & AV_PIX_FMT_FLAG_RGB)
750         out->colorspace = AVCOL_SPC_RGB;
751     else if (out->colorspace == AVCOL_SPC_RGB)
752         out->colorspace = AVCOL_SPC_UNSPECIFIED;
753 
754     if (scale->output_is_pal)
755         avpriv_set_systematic_pal2((uint32_t*)out->data[1], outlink->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : outlink->format);
756 
757     in_range = in->color_range;
758 
759     if (   scale->in_color_matrix
760         || scale->out_color_matrix
761         || scale-> in_range != AVCOL_RANGE_UNSPECIFIED
762         || in_range != AVCOL_RANGE_UNSPECIFIED
763         || scale->out_range != AVCOL_RANGE_UNSPECIFIED) {
764         int in_full, out_full, brightness, contrast, saturation;
765         const int *inv_table, *table;
766 
767         sws_getColorspaceDetails(scale->sws, (int **)&inv_table, &in_full,
768                                  (int **)&table, &out_full,
769                                  &brightness, &contrast, &saturation);
770 
771         if (scale->in_color_matrix)
772             inv_table = parse_yuv_type(scale->in_color_matrix, in->colorspace);
773         if (scale->out_color_matrix)
774             table     = parse_yuv_type(scale->out_color_matrix, AVCOL_SPC_UNSPECIFIED);
775         else if (scale->in_color_matrix)
776             table = inv_table;
777 
778         if (scale-> in_range != AVCOL_RANGE_UNSPECIFIED)
779             in_full  = (scale-> in_range == AVCOL_RANGE_JPEG);
780         else if (in_range != AVCOL_RANGE_UNSPECIFIED)
781             in_full  = (in_range == AVCOL_RANGE_JPEG);
782         if (scale->out_range != AVCOL_RANGE_UNSPECIFIED)
783             out_full = (scale->out_range == AVCOL_RANGE_JPEG);
784 
785         sws_setColorspaceDetails(scale->sws, inv_table, in_full,
786                                  table, out_full,
787                                  brightness, contrast, saturation);
788         if (scale->isws[0])
789             sws_setColorspaceDetails(scale->isws[0], inv_table, in_full,
790                                      table, out_full,
791                                      brightness, contrast, saturation);
792         if (scale->isws[1])
793             sws_setColorspaceDetails(scale->isws[1], inv_table, in_full,
794                                      table, out_full,
795                                      brightness, contrast, saturation);
796 
797         out->color_range = out_full ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
798     }
799 
800     av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
801               (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
802               (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
803               INT_MAX);
804 
805     if (scale->interlaced>0 || (scale->interlaced<0 && in->interlaced_frame)) {
806         scale_slice(link, out, in, scale->isws[0], 0, (link->h+1)/2, 2, 0);
807         scale_slice(link, out, in, scale->isws[1], 0,  link->h   /2, 2, 1);
808     } else if (scale->nb_slices) {
809         int i, slice_h, slice_start, slice_end = 0;
810         const int nb_slices = FFMIN(scale->nb_slices, link->h);
811         for (i = 0; i < nb_slices; i++) {
812             slice_start = slice_end;
813             slice_end   = (link->h * (i+1)) / nb_slices;
814             slice_h     = slice_end - slice_start;
815             scale_slice(link, out, in, scale->sws, slice_start, slice_h, 1, 0);
816         }
817     } else {
818         scale_slice(link, out, in, scale->sws, 0, link->h, 1, 0);
819     }
820 
821     av_frame_free(&in);
822     return 0;
823 }
824 
filter_frame(AVFilterLink * link,AVFrame * in)825 static int filter_frame(AVFilterLink *link, AVFrame *in)
826 {
827     AVFilterContext *ctx = link->dst;
828     AVFilterLink *outlink = ctx->outputs[0];
829     AVFrame *out;
830     int ret;
831 
832     ret = scale_frame(link, in, &out);
833     if (out)
834         return ff_filter_frame(outlink, out);
835 
836     return ret;
837 }
838 
filter_frame_ref(AVFilterLink * link,AVFrame * in)839 static int filter_frame_ref(AVFilterLink *link, AVFrame *in)
840 {
841     ScaleContext *scale = link->dst->priv;
842     AVFilterLink *outlink = link->dst->outputs[1];
843     int frame_changed;
844 
845     frame_changed = in->width  != link->w ||
846                     in->height != link->h ||
847                     in->format != link->format ||
848                     in->sample_aspect_ratio.den != link->sample_aspect_ratio.den ||
849                     in->sample_aspect_ratio.num != link->sample_aspect_ratio.num;
850 
851     if (frame_changed) {
852         link->format = in->format;
853         link->w = in->width;
854         link->h = in->height;
855         link->sample_aspect_ratio.num = in->sample_aspect_ratio.num;
856         link->sample_aspect_ratio.den = in->sample_aspect_ratio.den;
857 
858         config_props_ref(outlink);
859     }
860 
861     if (scale->eval_mode == EVAL_MODE_FRAME) {
862         scale->var_values[VAR_N] = link->frame_count_out;
863         scale->var_values[VAR_T] = TS2T(in->pts, link->time_base);
864         scale->var_values[VAR_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
865     }
866 
867     return ff_filter_frame(outlink, in);
868 }
869 
process_command(AVFilterContext * ctx,const char * cmd,const char * args,char * res,int res_len,int flags)870 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
871                            char *res, int res_len, int flags)
872 {
873     ScaleContext *scale = ctx->priv;
874     char *str_expr;
875     AVExpr **pexpr_ptr;
876     int ret, w, h;
877 
878     w = !strcmp(cmd, "width")  || !strcmp(cmd, "w");
879     h = !strcmp(cmd, "height")  || !strcmp(cmd, "h");
880 
881     if (w || h) {
882         str_expr = w ? scale->w_expr : scale->h_expr;
883         pexpr_ptr = w ? &scale->w_pexpr : &scale->h_pexpr;
884 
885         ret = scale_parse_expr(ctx, str_expr, pexpr_ptr, cmd, args);
886     } else
887         ret = AVERROR(ENOSYS);
888 
889     if (ret < 0)
890         av_log(ctx, AV_LOG_ERROR, "Failed to process command. Continuing with existing parameters.\n");
891 
892     return ret;
893 }
894 
895 #if FF_API_CHILD_CLASS_NEXT
child_class_next(const AVClass * prev)896 static const AVClass *child_class_next(const AVClass *prev)
897 {
898     return prev ? NULL : sws_get_class();
899 }
900 #endif
901 
child_class_iterate(void ** iter)902 static const AVClass *child_class_iterate(void **iter)
903 {
904     const AVClass *c = *iter ? NULL : sws_get_class();
905     *iter = (void*)(uintptr_t)c;
906     return c;
907 }
908 
909 #define OFFSET(x) offsetof(ScaleContext, x)
910 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
911 #define TFLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
912 
913 static const AVOption scale_options[] = {
914     { "w",     "Output video width",          OFFSET(w_expr),    AV_OPT_TYPE_STRING,        .flags = TFLAGS },
915     { "width", "Output video width",          OFFSET(w_expr),    AV_OPT_TYPE_STRING,        .flags = TFLAGS },
916     { "h",     "Output video height",         OFFSET(h_expr),    AV_OPT_TYPE_STRING,        .flags = TFLAGS },
917     { "height","Output video height",         OFFSET(h_expr),    AV_OPT_TYPE_STRING,        .flags = TFLAGS },
918     { "flags", "Flags to pass to libswscale", OFFSET(flags_str), AV_OPT_TYPE_STRING, { .str = "bilinear" }, .flags = FLAGS },
919     { "interl", "set interlacing", OFFSET(interlaced), AV_OPT_TYPE_BOOL, {.i64 = 0 }, -1, 1, FLAGS },
920     { "size",   "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
921     { "s",      "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
922     {  "in_color_matrix", "set input YCbCr type",   OFFSET(in_color_matrix),  AV_OPT_TYPE_STRING, { .str = "auto" }, .flags = FLAGS, "color" },
923     { "out_color_matrix", "set output YCbCr type",  OFFSET(out_color_matrix), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = FLAGS,  "color"},
924         { "auto",        NULL, 0, AV_OPT_TYPE_CONST, { .str = "auto" },      0, 0, FLAGS, "color" },
925         { "bt601",       NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt601" },     0, 0, FLAGS, "color" },
926         { "bt470",       NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt470" },     0, 0, FLAGS, "color" },
927         { "smpte170m",   NULL, 0, AV_OPT_TYPE_CONST, { .str = "smpte170m" }, 0, 0, FLAGS, "color" },
928         { "bt709",       NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt709" },     0, 0, FLAGS, "color" },
929         { "fcc",         NULL, 0, AV_OPT_TYPE_CONST, { .str = "fcc" },       0, 0, FLAGS, "color" },
930         { "smpte240m",   NULL, 0, AV_OPT_TYPE_CONST, { .str = "smpte240m" }, 0, 0, FLAGS, "color" },
931         { "bt2020",      NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt2020" },    0, 0, FLAGS, "color" },
932     {  "in_range", "set input color range",  OFFSET( in_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
933     { "out_range", "set output color range", OFFSET(out_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
934     { "auto",   NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 0, FLAGS, "range" },
935     { "unknown", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 0, FLAGS, "range" },
936     { "full",   NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
937     { "limited",NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
938     { "jpeg",   NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
939     { "mpeg",   NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
940     { "tv",     NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
941     { "pc",     NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
942     { "in_v_chr_pos",   "input vertical chroma position in luma grid/256"  ,   OFFSET(in_v_chr_pos),  AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
943     { "in_h_chr_pos",   "input horizontal chroma position in luma grid/256",   OFFSET(in_h_chr_pos),  AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
944     { "out_v_chr_pos",   "output vertical chroma position in luma grid/256"  , OFFSET(out_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
945     { "out_h_chr_pos",   "output horizontal chroma position in luma grid/256", OFFSET(out_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
946     { "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" },
947     { "disable",  NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0 }, 0, 0, FLAGS, "force_oar" },
948     { "decrease", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, FLAGS, "force_oar" },
949     { "increase", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2 }, 0, 0, FLAGS, "force_oar" },
950     { "force_divisible_by", "enforce that the output resolution is divisible by a defined integer when force_original_aspect_ratio is used", OFFSET(force_divisible_by), AV_OPT_TYPE_INT, { .i64 = 1}, 1, 256, FLAGS },
951     { "param0", "Scaler param 0",             OFFSET(param[0]),  AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT  }, INT_MIN, INT_MAX, FLAGS },
952     { "param1", "Scaler param 1",             OFFSET(param[1]),  AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT  }, INT_MIN, INT_MAX, FLAGS },
953     { "nb_slices", "set the number of slices (debug purpose only)", OFFSET(nb_slices), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
954     { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
955          { "init",  "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT},  .flags = FLAGS, .unit = "eval" },
956          { "frame", "eval expressions during initialization and per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
957     { NULL }
958 };
959 
960 static const AVClass scale_class = {
961     .class_name       = "scale",
962     .item_name        = av_default_item_name,
963     .option           = scale_options,
964     .version          = LIBAVUTIL_VERSION_INT,
965     .category         = AV_CLASS_CATEGORY_FILTER,
966 #if FF_API_CHILD_CLASS_NEXT
967     .child_class_next = child_class_next,
968 #endif
969     .child_class_iterate = child_class_iterate,
970 };
971 
972 static const AVFilterPad avfilter_vf_scale_inputs[] = {
973     {
974         .name         = "default",
975         .type         = AVMEDIA_TYPE_VIDEO,
976         .filter_frame = filter_frame,
977     },
978     { NULL }
979 };
980 
981 static const AVFilterPad avfilter_vf_scale_outputs[] = {
982     {
983         .name         = "default",
984         .type         = AVMEDIA_TYPE_VIDEO,
985         .config_props = config_props,
986     },
987     { NULL }
988 };
989 
990 AVFilter ff_vf_scale = {
991     .name            = "scale",
992     .description     = NULL_IF_CONFIG_SMALL("Scale the input video size and/or convert the image format."),
993     .init_dict       = init_dict,
994     .uninit          = uninit,
995     .query_formats   = query_formats,
996     .priv_size       = sizeof(ScaleContext),
997     .priv_class      = &scale_class,
998     .inputs          = avfilter_vf_scale_inputs,
999     .outputs         = avfilter_vf_scale_outputs,
1000     .process_command = process_command,
1001 };
1002 
1003 static const AVClass scale2ref_class = {
1004     .class_name       = "scale2ref",
1005     .item_name        = av_default_item_name,
1006     .option           = scale_options,
1007     .version          = LIBAVUTIL_VERSION_INT,
1008     .category         = AV_CLASS_CATEGORY_FILTER,
1009 #if FF_API_CHILD_CLASS_NEXT
1010     .child_class_next = child_class_next,
1011 #endif
1012     .child_class_iterate = child_class_iterate,
1013 };
1014 
1015 static const AVFilterPad avfilter_vf_scale2ref_inputs[] = {
1016     {
1017         .name         = "default",
1018         .type         = AVMEDIA_TYPE_VIDEO,
1019         .filter_frame = filter_frame,
1020     },
1021     {
1022         .name         = "ref",
1023         .type         = AVMEDIA_TYPE_VIDEO,
1024         .filter_frame = filter_frame_ref,
1025     },
1026     { NULL }
1027 };
1028 
1029 static const AVFilterPad avfilter_vf_scale2ref_outputs[] = {
1030     {
1031         .name         = "default",
1032         .type         = AVMEDIA_TYPE_VIDEO,
1033         .config_props = config_props,
1034         .request_frame= request_frame,
1035     },
1036     {
1037         .name         = "ref",
1038         .type         = AVMEDIA_TYPE_VIDEO,
1039         .config_props = config_props_ref,
1040         .request_frame= request_frame_ref,
1041     },
1042     { NULL }
1043 };
1044 
1045 AVFilter ff_vf_scale2ref = {
1046     .name            = "scale2ref",
1047     .description     = NULL_IF_CONFIG_SMALL("Scale the input video size and/or convert the image format to the given reference."),
1048     .init_dict       = init_dict,
1049     .uninit          = uninit,
1050     .query_formats   = query_formats,
1051     .priv_size       = sizeof(ScaleContext),
1052     .priv_class      = &scale2ref_class,
1053     .inputs          = avfilter_vf_scale2ref_inputs,
1054     .outputs         = avfilter_vf_scale2ref_outputs,
1055     .process_command = process_command,
1056 };
1057