2 * Copyright (c) 2008 vmrsss
3 * Copyright (c) 2009 Stefano Sabatini
5 * This file is part of FFmpeg.
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.
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.
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
24 * video padding filter
31 #include "libavutil/avstring.h"
32 #include "libavutil/common.h"
33 #include "libavutil/eval.h"
34 #include "libavutil/pixdesc.h"
35 #include "libavutil/colorspace.h"
36 #include "libavutil/avassert.h"
37 #include "libavutil/imgutils.h"
38 #include "libavutil/opt.h"
39 #include "libavutil/parseutils.h"
40 #include "libavutil/mathematics.h"
41 #include "libavutil/opt.h"
43 #include "drawutils.h"
45 static const char *const var_names[] = {
75 static int query_formats(AVFilterContext *ctx)
77 ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
83 int w, h; ///< output dimensions, a value of 0 will result in the input size
84 int x, y; ///< offsets of the input area with respect to the padded area
85 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
87 char *w_expr; ///< width expression string
88 char *h_expr; ///< height expression string
89 char *x_expr; ///< width expression string
90 char *y_expr; ///< height expression string
91 uint8_t rgba_color[4]; ///< color for the padding area
96 static int config_input(AVFilterLink *inlink)
98 AVFilterContext *ctx = inlink->dst;
99 PadContext *s = ctx->priv;
101 double var_values[VARS_NB], res;
104 ff_draw_init(&s->draw, inlink->format, 0);
105 ff_draw_color(&s->draw, &s->color, s->rgba_color);
107 var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
108 var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
109 var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
110 var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
111 var_values[VAR_A] = (double) inlink->w / inlink->h;
112 var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
113 (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
114 var_values[VAR_DAR] = var_values[VAR_A] * var_values[VAR_SAR];
115 var_values[VAR_HSUB] = 1 << s->draw.hsub_max;
116 var_values[VAR_VSUB] = 1 << s->draw.vsub_max;
118 /* evaluate width and height */
119 av_expr_parse_and_eval(&res, (expr = s->w_expr),
120 var_names, var_values,
121 NULL, NULL, NULL, NULL, NULL, 0, ctx);
122 s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
123 if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
124 var_names, var_values,
125 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
127 s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
128 /* evaluate the width again, as it may depend on the evaluated output height */
129 if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
130 var_names, var_values,
131 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
133 s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
135 /* evaluate x and y */
136 av_expr_parse_and_eval(&res, (expr = s->x_expr),
137 var_names, var_values,
138 NULL, NULL, NULL, NULL, NULL, 0, ctx);
139 s->x = var_values[VAR_X] = res;
140 if ((ret = av_expr_parse_and_eval(&res, (expr = s->y_expr),
141 var_names, var_values,
142 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
144 s->y = var_values[VAR_Y] = res;
145 /* evaluate x again, as it may depend on the evaluated y value */
146 if ((ret = av_expr_parse_and_eval(&res, (expr = s->x_expr),
147 var_names, var_values,
148 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
150 s->x = var_values[VAR_X] = res;
152 /* sanity check params */
153 if (s->w < 0 || s->h < 0 || s->x < 0 || s->y < 0) {
154 av_log(ctx, AV_LOG_ERROR, "Negative values are not acceptable.\n");
155 return AVERROR(EINVAL);
163 s->w = ff_draw_round_to_sub(&s->draw, 0, -1, s->w);
164 s->h = ff_draw_round_to_sub(&s->draw, 1, -1, s->h);
165 s->x = ff_draw_round_to_sub(&s->draw, 0, -1, s->x);
166 s->y = ff_draw_round_to_sub(&s->draw, 1, -1, s->y);
167 s->in_w = ff_draw_round_to_sub(&s->draw, 0, -1, inlink->w);
168 s->in_h = ff_draw_round_to_sub(&s->draw, 1, -1, inlink->h);
170 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",
171 inlink->w, inlink->h, s->w, s->h, s->x, s->y,
172 s->rgba_color[0], s->rgba_color[1], s->rgba_color[2], s->rgba_color[3]);
174 if (s->x < 0 || s->y < 0 ||
175 s->w <= 0 || s->h <= 0 ||
176 (unsigned)s->x + (unsigned)inlink->w > s->w ||
177 (unsigned)s->y + (unsigned)inlink->h > s->h) {
178 av_log(ctx, AV_LOG_ERROR,
179 "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
180 s->x, s->y, s->x + inlink->w, s->y + inlink->h, s->w, s->h);
181 return AVERROR(EINVAL);
187 av_log(NULL, AV_LOG_ERROR,
188 "Error when evaluating the expression '%s'\n", expr);
193 static int config_output(AVFilterLink *outlink)
195 PadContext *s = outlink->src->priv;
202 static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
204 PadContext *s = inlink->dst->priv;
206 AVFrame *frame = ff_get_video_buffer(inlink->dst->outputs[0],
207 w + (s->w - s->in_w),
208 h + (s->h - s->in_h));
217 for (plane = 0; plane < 4 && frame->data[plane]; plane++) {
218 int hsub = s->draw.hsub[plane];
219 int vsub = s->draw.vsub[plane];
220 frame->data[plane] += (s->x >> hsub) * s->draw.pixelstep[plane] +
221 (s->y >> vsub) * frame->linesize[plane];
227 /* check whether each plane in this buffer can be padded without copying */
228 static int buffer_needs_copy(PadContext *s, AVFrame *frame, AVBufferRef *buf)
230 int planes[4] = { -1, -1, -1, -1}, *p = planes;
233 /* get all planes in this buffer */
234 for (i = 0; i < FF_ARRAY_ELEMS(planes) && frame->data[i]; i++) {
235 if (av_frame_get_plane_buffer(frame, i) == buf)
239 /* for each plane in this buffer, check that it can be padded without
240 * going over buffer bounds or other planes */
241 for (i = 0; i < FF_ARRAY_ELEMS(planes) && planes[i] >= 0; i++) {
242 int hsub = s->draw.hsub[planes[i]];
243 int vsub = s->draw.vsub[planes[i]];
245 uint8_t *start = frame->data[planes[i]];
246 uint8_t *end = start + (frame->height >> vsub) *
247 frame->linesize[planes[i]];
249 /* amount of free space needed before the start and after the end
251 ptrdiff_t req_start = (s->x >> hsub) * s->draw.pixelstep[planes[i]] +
252 (s->y >> vsub) * frame->linesize[planes[i]];
253 ptrdiff_t req_end = ((s->w - s->x - frame->width) >> hsub) *
254 s->draw.pixelstep[planes[i]] +
255 (s->y >> vsub) * frame->linesize[planes[i]];
257 if (frame->linesize[planes[i]] < (s->w >> hsub) * s->draw.pixelstep[planes[i]])
259 if (start - buf->data < req_start ||
260 (buf->data + buf->size) - end < req_end)
263 for (j = 0; j < FF_ARRAY_ELEMS(planes) && planes[j] >= 0; j++) {
264 int vsub1 = s->draw.vsub[planes[j]];
265 uint8_t *start1 = frame->data[planes[j]];
266 uint8_t *end1 = start1 + (frame->height >> vsub1) *
267 frame->linesize[planes[j]];
271 if (FFSIGN(start - end1) != FFSIGN(start - end1 - req_start) ||
272 FFSIGN(end - start1) != FFSIGN(end - start1 + req_end))
280 static int frame_needs_copy(PadContext *s, AVFrame *frame)
284 if (!av_frame_is_writable(frame))
287 for (i = 0; i < 4 && frame->buf[i]; i++)
288 if (buffer_needs_copy(s, frame, frame->buf[i]))
293 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
295 PadContext *s = inlink->dst->priv;
297 int needs_copy = frame_needs_copy(s, in);
300 av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
301 out = ff_get_video_buffer(inlink->dst->outputs[0],
302 FFMAX(inlink->w, s->w),
303 FFMAX(inlink->h, s->h));
306 return AVERROR(ENOMEM);
309 av_frame_copy_props(out, in);
314 for (i = 0; i < 4 && out->data[i]; i++) {
315 int hsub = s->draw.hsub[i];
316 int vsub = s->draw.vsub[i];
317 out->data[i] -= (s->x >> hsub) * s->draw.pixelstep[i] +
318 (s->y >> vsub) * out->linesize[i];
324 ff_fill_rectangle(&s->draw, &s->color,
325 out->data, out->linesize,
330 if (s->h > s->y + s->in_h) {
331 ff_fill_rectangle(&s->draw, &s->color,
332 out->data, out->linesize,
333 0, s->y + s->in_h, s->w, s->h - s->y - s->in_h);
337 ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
338 0, s->y, s->x, in->height);
341 ff_copy_rectangle2(&s->draw,
342 out->data, out->linesize, in->data, in->linesize,
343 s->x, s->y, 0, 0, in->width, in->height);
347 ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
348 s->x + s->in_w, s->y, s->w - s->x - s->in_w,
356 return ff_filter_frame(inlink->dst->outputs[0], out);
359 #define OFFSET(x) offsetof(PadContext, x)
360 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
362 static const AVOption pad_options[] = {
363 { "width", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
364 { "w", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
365 { "height", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
366 { "h", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
367 { "x", "set the x offset expression for the input image position", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
368 { "y", "set the y offset expression for the input image position", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
369 { "color", "set the color of the padded area border", OFFSET(rgba_color), AV_OPT_TYPE_COLOR, {.str = "black"}, .flags = FLAGS },
373 AVFILTER_DEFINE_CLASS(pad);
375 static const AVFilterPad avfilter_vf_pad_inputs[] = {
378 .type = AVMEDIA_TYPE_VIDEO,
379 .config_props = config_input,
380 .get_video_buffer = get_video_buffer,
381 .filter_frame = filter_frame,
386 static const AVFilterPad avfilter_vf_pad_outputs[] = {
389 .type = AVMEDIA_TYPE_VIDEO,
390 .config_props = config_output,
395 AVFilter avfilter_vf_pad = {
397 .description = NULL_IF_CONFIG_SMALL("Pad input image to width:height[:x:y[:color]] (default x and y: 0, default color: black)."),
399 .priv_size = sizeof(PadContext),
400 .priv_class = &pad_class,
401 .query_formats = query_formats,
403 .inputs = avfilter_vf_pad_inputs,
405 .outputs = avfilter_vf_pad_outputs,