1 /*
2 * Copyright (c) 2008 vmrsss
3 * Copyright (c) 2009 Stefano Sabatini
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * video padding filter
25 */
26
27 #include <float.h> /* DBL_MAX */
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/common.h"
35 #include "libavutil/eval.h"
36 #include "libavutil/pixdesc.h"
37 #include "libavutil/colorspace.h"
38 #include "libavutil/imgutils.h"
39 #include "libavutil/parseutils.h"
40 #include "libavutil/mathematics.h"
41 #include "libavutil/opt.h"
42
43 #include "drawutils.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 "x",
51 "y",
52 "a",
53 "sar",
54 "dar",
55 "hsub",
56 "vsub",
57 NULL
58 };
59
60 enum var_name {
61 VAR_IN_W, VAR_IW,
62 VAR_IN_H, VAR_IH,
63 VAR_OUT_W, VAR_OW,
64 VAR_OUT_H, VAR_OH,
65 VAR_X,
66 VAR_Y,
67 VAR_A,
68 VAR_SAR,
69 VAR_DAR,
70 VAR_HSUB,
71 VAR_VSUB,
72 VARS_NB
73 };
74
query_formats(AVFilterContext * ctx)75 static int query_formats(AVFilterContext *ctx)
76 {
77 return ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
78 }
79
80 enum EvalMode {
81 EVAL_MODE_INIT,
82 EVAL_MODE_FRAME,
83 EVAL_MODE_NB
84 };
85
86 typedef struct PadContext {
87 const AVClass *class;
88 int w, h; ///< output dimensions, a value of 0 will result in the input size
89 int x, y; ///< offsets of the input area with respect to the padded area
90 int in_w, in_h; ///< width and height for the padded input video, which has to be aligned to the chroma values in order to avoid chroma issues
91 int inlink_w, inlink_h;
92 AVRational aspect;
93
94 char *w_expr; ///< width expression string
95 char *h_expr; ///< height expression string
96 char *x_expr; ///< width expression string
97 char *y_expr; ///< height expression string
98 uint8_t rgba_color[4]; ///< color for the padding area
99 FFDrawContext draw;
100 FFDrawColor color;
101
102 int eval_mode; ///< expression evaluation mode
103 } PadContext;
104
config_input(AVFilterLink * inlink)105 static int config_input(AVFilterLink *inlink)
106 {
107 AVFilterContext *ctx = inlink->dst;
108 PadContext *s = ctx->priv;
109 AVRational adjusted_aspect = s->aspect;
110 int ret;
111 double var_values[VARS_NB], res;
112 char *expr;
113
114 ff_draw_init(&s->draw, inlink->format, 0);
115 ff_draw_color(&s->draw, &s->color, s->rgba_color);
116
117 var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
118 var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
119 var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
120 var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
121 var_values[VAR_A] = (double) inlink->w / inlink->h;
122 var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
123 (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
124 var_values[VAR_DAR] = var_values[VAR_A] * var_values[VAR_SAR];
125 var_values[VAR_HSUB] = 1 << s->draw.hsub_max;
126 var_values[VAR_VSUB] = 1 << s->draw.vsub_max;
127
128 /* evaluate width and height */
129 av_expr_parse_and_eval(&res, (expr = s->w_expr),
130 var_names, var_values,
131 NULL, NULL, NULL, NULL, NULL, 0, ctx);
132 s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
133 if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
134 var_names, var_values,
135 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
136 goto eval_fail;
137 s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
138 if (!s->h)
139 var_values[VAR_OUT_H] = var_values[VAR_OH] = s->h = inlink->h;
140
141 /* evaluate the width again, as it may depend on the evaluated output height */
142 if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
143 var_names, var_values,
144 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
145 goto eval_fail;
146 s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
147 if (!s->w)
148 var_values[VAR_OUT_W] = var_values[VAR_OW] = s->w = inlink->w;
149
150 if (adjusted_aspect.num && adjusted_aspect.den) {
151 adjusted_aspect = av_div_q(adjusted_aspect, inlink->sample_aspect_ratio);
152 if (s->h < av_rescale(s->w, adjusted_aspect.den, adjusted_aspect.num)) {
153 s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = av_rescale(s->w, adjusted_aspect.den, adjusted_aspect.num);
154 } else {
155 s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = av_rescale(s->h, adjusted_aspect.num, adjusted_aspect.den);
156 }
157 }
158
159 /* evaluate x and y */
160 av_expr_parse_and_eval(&res, (expr = s->x_expr),
161 var_names, var_values,
162 NULL, NULL, NULL, NULL, NULL, 0, ctx);
163 s->x = var_values[VAR_X] = res;
164 if ((ret = av_expr_parse_and_eval(&res, (expr = s->y_expr),
165 var_names, var_values,
166 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
167 goto eval_fail;
168 s->y = var_values[VAR_Y] = res;
169 /* evaluate x again, as it may depend on the evaluated y value */
170 if ((ret = av_expr_parse_and_eval(&res, (expr = s->x_expr),
171 var_names, var_values,
172 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
173 goto eval_fail;
174 s->x = var_values[VAR_X] = res;
175
176 if (s->x < 0 || s->x + inlink->w > s->w)
177 s->x = var_values[VAR_X] = (s->w - inlink->w) / 2;
178 if (s->y < 0 || s->y + inlink->h > s->h)
179 s->y = var_values[VAR_Y] = (s->h - inlink->h) / 2;
180
181 s->w = ff_draw_round_to_sub(&s->draw, 0, -1, s->w);
182 s->h = ff_draw_round_to_sub(&s->draw, 1, -1, s->h);
183 /* sanity check params */
184 if (s->w < inlink->w || s->h < inlink->h) {
185 av_log(ctx, AV_LOG_ERROR, "Padded dimensions cannot be smaller than input dimensions.\n");
186 return AVERROR(EINVAL);
187 }
188
189 s->x = ff_draw_round_to_sub(&s->draw, 0, -1, s->x);
190 s->y = ff_draw_round_to_sub(&s->draw, 1, -1, s->y);
191 s->in_w = ff_draw_round_to_sub(&s->draw, 0, -1, inlink->w);
192 s->in_h = ff_draw_round_to_sub(&s->draw, 1, -1, inlink->h);
193 s->inlink_w = inlink->w;
194 s->inlink_h = inlink->h;
195
196 av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d -> w:%d h:%d x:%d y:%d color:0x%02X%02X%02X%02X\n",
197 inlink->w, inlink->h, s->w, s->h, s->x, s->y,
198 s->rgba_color[0], s->rgba_color[1], s->rgba_color[2], s->rgba_color[3]);
199
200 if (s->x < 0 || s->y < 0 ||
201 s->w <= 0 || s->h <= 0 ||
202 (unsigned)s->x + (unsigned)inlink->w > s->w ||
203 (unsigned)s->y + (unsigned)inlink->h > s->h) {
204 av_log(ctx, AV_LOG_ERROR,
205 "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
206 s->x, s->y, s->x + inlink->w, s->y + inlink->h, s->w, s->h);
207 return AVERROR(EINVAL);
208 }
209
210 return 0;
211
212 eval_fail:
213 av_log(ctx, AV_LOG_ERROR,
214 "Error when evaluating the expression '%s'\n", expr);
215 return ret;
216
217 }
218
config_output(AVFilterLink * outlink)219 static int config_output(AVFilterLink *outlink)
220 {
221 PadContext *s = outlink->src->priv;
222
223 outlink->w = s->w;
224 outlink->h = s->h;
225 return 0;
226 }
227
get_video_buffer(AVFilterLink * inlink,int w,int h)228 static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
229 {
230 PadContext *s = inlink->dst->priv;
231 AVFrame *frame;
232 int plane;
233
234 if (s->inlink_w <= 0)
235 return NULL;
236
237 frame = ff_get_video_buffer(inlink->dst->outputs[0],
238 w + (s->w - s->in_w),
239 h + (s->h - s->in_h) + (s->x > 0));
240
241 if (!frame)
242 return NULL;
243
244 frame->width = w;
245 frame->height = h;
246
247 for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
248 int hsub = s->draw.hsub[plane];
249 int vsub = s->draw.vsub[plane];
250 frame->data[plane] += (s->x >> hsub) * s->draw.pixelstep[plane] +
251 (s->y >> vsub) * frame->linesize[plane];
252 }
253
254 return frame;
255 }
256
257 /* check whether each plane in this buffer can be padded without copying */
buffer_needs_copy(PadContext * s,AVFrame * frame,AVBufferRef * buf)258 static int buffer_needs_copy(PadContext *s, AVFrame *frame, AVBufferRef *buf)
259 {
260 int planes[4] = { -1, -1, -1, -1}, *p = planes;
261 int i, j;
262
263 /* get all planes in this buffer */
264 for (i = 0; i < FF_ARRAY_ELEMS(planes) && frame->data[i]; i++) {
265 if (av_frame_get_plane_buffer(frame, i) == buf)
266 *p++ = i;
267 }
268
269 /* for each plane in this buffer, check that it can be padded without
270 * going over buffer bounds or other planes */
271 for (i = 0; i < FF_ARRAY_ELEMS(planes) && planes[i] >= 0; i++) {
272 int hsub = s->draw.hsub[planes[i]];
273 int vsub = s->draw.vsub[planes[i]];
274
275 uint8_t *start = frame->data[planes[i]];
276 uint8_t *end = start + (frame->height >> vsub) *
277 frame->linesize[planes[i]];
278
279 /* amount of free space needed before the start and after the end
280 * of the plane */
281 ptrdiff_t req_start = (s->x >> hsub) * s->draw.pixelstep[planes[i]] +
282 (s->y >> vsub) * frame->linesize[planes[i]];
283 ptrdiff_t req_end = ((s->w - s->x - frame->width) >> hsub) *
284 s->draw.pixelstep[planes[i]] +
285 ((s->h - s->y - frame->height) >> vsub) * frame->linesize[planes[i]];
286
287 if (frame->linesize[planes[i]] < (s->w >> hsub) * s->draw.pixelstep[planes[i]])
288 return 1;
289 if (start - buf->data < req_start ||
290 (buf->data + buf->size) - end < req_end)
291 return 1;
292
293 for (j = 0; j < FF_ARRAY_ELEMS(planes) && planes[j] >= 0; j++) {
294 int vsub1 = s->draw.vsub[planes[j]];
295 uint8_t *start1 = frame->data[planes[j]];
296 uint8_t *end1 = start1 + (frame->height >> vsub1) *
297 frame->linesize[planes[j]];
298 if (i == j)
299 continue;
300
301 if (FFSIGN(start - end1) != FFSIGN(start - end1 - req_start) ||
302 FFSIGN(end - start1) != FFSIGN(end - start1 + req_end))
303 return 1;
304 }
305 }
306
307 return 0;
308 }
309
frame_needs_copy(PadContext * s,AVFrame * frame)310 static int frame_needs_copy(PadContext *s, AVFrame *frame)
311 {
312 int i;
313
314 if (!av_frame_is_writable(frame))
315 return 1;
316
317 for (i = 0; i < 4 && frame->buf[i]; i++)
318 if (buffer_needs_copy(s, frame, frame->buf[i]))
319 return 1;
320 return 0;
321 }
322
filter_frame(AVFilterLink * inlink,AVFrame * in)323 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
324 {
325 PadContext *s = inlink->dst->priv;
326 AVFilterLink *outlink = inlink->dst->outputs[0];
327 AVFrame *out;
328 int needs_copy;
329 if(s->eval_mode == EVAL_MODE_FRAME && (
330 in->width != s->inlink_w
331 || in->height != s->inlink_h
332 || in->format != outlink->format
333 || in->sample_aspect_ratio.den != outlink->sample_aspect_ratio.den || in->sample_aspect_ratio.num != outlink->sample_aspect_ratio.num)) {
334 int ret;
335
336 inlink->dst->inputs[0]->format = in->format;
337 inlink->dst->inputs[0]->w = in->width;
338 inlink->dst->inputs[0]->h = in->height;
339
340 inlink->dst->inputs[0]->sample_aspect_ratio.den = in->sample_aspect_ratio.den;
341 inlink->dst->inputs[0]->sample_aspect_ratio.num = in->sample_aspect_ratio.num;
342
343
344 if ((ret = config_input(inlink)) < 0) {
345 s->inlink_w = -1;
346 return ret;
347 }
348 if ((ret = config_output(outlink)) < 0) {
349 s->inlink_w = -1;
350 return ret;
351 }
352 }
353
354 needs_copy = frame_needs_copy(s, in);
355
356 if (needs_copy) {
357 av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
358 out = ff_get_video_buffer(inlink->dst->outputs[0],
359 FFMAX(inlink->w, s->w),
360 FFMAX(inlink->h, s->h));
361 if (!out) {
362 av_frame_free(&in);
363 return AVERROR(ENOMEM);
364 }
365
366 av_frame_copy_props(out, in);
367 } else {
368 int i;
369
370 out = in;
371 for (i = 0; i < 4 && out->data[i] && out->linesize[i]; i++) {
372 int hsub = s->draw.hsub[i];
373 int vsub = s->draw.vsub[i];
374 out->data[i] -= (s->x >> hsub) * s->draw.pixelstep[i] +
375 (s->y >> vsub) * out->linesize[i];
376 }
377 }
378
379 /* top bar */
380 if (s->y) {
381 ff_fill_rectangle(&s->draw, &s->color,
382 out->data, out->linesize,
383 0, 0, s->w, s->y);
384 }
385
386 /* bottom bar */
387 if (s->h > s->y + s->in_h) {
388 ff_fill_rectangle(&s->draw, &s->color,
389 out->data, out->linesize,
390 0, s->y + s->in_h, s->w, s->h - s->y - s->in_h);
391 }
392
393 /* left border */
394 ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
395 0, s->y, s->x, in->height);
396
397 if (needs_copy) {
398 ff_copy_rectangle2(&s->draw,
399 out->data, out->linesize, in->data, in->linesize,
400 s->x, s->y, 0, 0, in->width, in->height);
401 }
402
403 /* right border */
404 ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
405 s->x + s->in_w, s->y, s->w - s->x - s->in_w,
406 in->height);
407
408 out->width = s->w;
409 out->height = s->h;
410
411 if (in != out)
412 av_frame_free(&in);
413 return ff_filter_frame(inlink->dst->outputs[0], out);
414 }
415
416 #define OFFSET(x) offsetof(PadContext, x)
417 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
418
419 static const AVOption pad_options[] = {
420 { "width", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, 0, 0, FLAGS },
421 { "w", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, 0, 0, FLAGS },
422 { "height", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, FLAGS },
423 { "h", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, FLAGS },
424 { "x", "set the x offset expression for the input image position", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
425 { "y", "set the y offset expression for the input image position", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
426 { "color", "set the color of the padded area border", OFFSET(rgba_color), AV_OPT_TYPE_COLOR, {.str = "black"}, .flags = FLAGS },
427 { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
428 { "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
429 { "frame", "eval expressions during initialization and per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
430 { "aspect", "pad to fit an aspect instead of a resolution", OFFSET(aspect), AV_OPT_TYPE_RATIONAL, {.dbl = 0}, 0, DBL_MAX, FLAGS },
431 { NULL }
432 };
433
434 AVFILTER_DEFINE_CLASS(pad);
435
436 static const AVFilterPad avfilter_vf_pad_inputs[] = {
437 {
438 .name = "default",
439 .type = AVMEDIA_TYPE_VIDEO,
440 .config_props = config_input,
441 .get_video_buffer = get_video_buffer,
442 .filter_frame = filter_frame,
443 },
444 { NULL }
445 };
446
447 static const AVFilterPad avfilter_vf_pad_outputs[] = {
448 {
449 .name = "default",
450 .type = AVMEDIA_TYPE_VIDEO,
451 .config_props = config_output,
452 },
453 { NULL }
454 };
455
456 AVFilter ff_vf_pad = {
457 .name = "pad",
458 .description = NULL_IF_CONFIG_SMALL("Pad the input video."),
459 .priv_size = sizeof(PadContext),
460 .priv_class = &pad_class,
461 .query_formats = query_formats,
462 .inputs = avfilter_vf_pad_inputs,
463 .outputs = avfilter_vf_pad_outputs,
464 };
465