2 * Copyright (c) 2007 Bobby Bingham
4 * This file is part of FFmpeg.
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.
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.
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
34 #include "libavutil/eval.h"
35 #include "libavutil/avstring.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/libm.h"
38 #include "libavutil/imgutils.h"
39 #include "libavutil/mathematics.h"
40 #include "libavutil/opt.h"
42 static const char *const var_names[] = {
43 "in_w", "iw", ///< width of the input video
44 "in_h", "ih", ///< height of the input video
45 "out_w", "ow", ///< width of the cropped video
46 "out_h", "oh", ///< height of the cropped video
54 "n", ///< number of frame
55 "pos", ///< position in the file
56 "t", ///< timestamp expressed in seconds
79 int x; ///< x offset of the non-cropped area with respect to the input area
80 int y; ///< y offset of the non-cropped area with respect to the input area
81 int w; ///< width of the cropped area
82 int h; ///< height of the cropped area
84 AVRational out_sar; ///< output sample aspect ratio
85 int keep_aspect; ///< keep display aspect ratio when cropping
87 int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
88 int hsub, vsub; ///< chroma subsampling
89 char *x_expr, *y_expr, *w_expr, *h_expr;
90 AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */
91 double var_values[VAR_VARS_NB];
94 static int query_formats(AVFilterContext *ctx)
96 static const enum AVPixelFormat pix_fmts[] = {
97 AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGB48LE,
98 AV_PIX_FMT_BGR48BE, AV_PIX_FMT_BGR48LE,
99 AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA,
100 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA,
101 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
102 AV_PIX_FMT_RGB565BE, AV_PIX_FMT_RGB565LE,
103 AV_PIX_FMT_RGB555BE, AV_PIX_FMT_RGB555LE,
104 AV_PIX_FMT_BGR565BE, AV_PIX_FMT_BGR565LE,
105 AV_PIX_FMT_BGR555BE, AV_PIX_FMT_BGR555LE,
106 AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_GRAY16LE,
107 AV_PIX_FMT_YUV420P16LE, AV_PIX_FMT_YUV420P16BE,
108 AV_PIX_FMT_YUV422P16LE, AV_PIX_FMT_YUV422P16BE,
109 AV_PIX_FMT_YUV444P16LE, AV_PIX_FMT_YUV444P16BE,
110 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,
111 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P,
112 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P,
113 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
114 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ440P,
116 AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8,
117 AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE,
118 AV_PIX_FMT_PAL8, AV_PIX_FMT_GRAY8,
122 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
127 static av_cold void uninit(AVFilterContext *ctx)
129 CropContext *crop = ctx->priv;
131 av_expr_free(crop->x_pexpr); crop->x_pexpr = NULL;
132 av_expr_free(crop->y_pexpr); crop->y_pexpr = NULL;
135 static inline int normalize_double(int *n, double d)
140 ret = AVERROR(EINVAL);
141 } else if (d > INT_MAX || d < INT_MIN) {
142 *n = d > INT_MAX ? INT_MAX : INT_MIN;
143 ret = AVERROR(EINVAL);
150 static int config_input(AVFilterLink *link)
152 AVFilterContext *ctx = link->dst;
153 CropContext *crop = ctx->priv;
154 const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(link->format);
159 crop->var_values[VAR_IN_W] = crop->var_values[VAR_IW] = ctx->inputs[0]->w;
160 crop->var_values[VAR_IN_H] = crop->var_values[VAR_IH] = ctx->inputs[0]->h;
161 crop->var_values[VAR_A] = (float) link->w / link->h;
162 crop->var_values[VAR_SAR] = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
163 crop->var_values[VAR_DAR] = crop->var_values[VAR_A] * crop->var_values[VAR_SAR];
164 crop->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
165 crop->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
166 crop->var_values[VAR_X] = NAN;
167 crop->var_values[VAR_Y] = NAN;
168 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = NAN;
169 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = NAN;
170 crop->var_values[VAR_N] = 0;
171 crop->var_values[VAR_T] = NAN;
173 av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc);
174 crop->hsub = pix_desc->log2_chroma_w;
175 crop->vsub = pix_desc->log2_chroma_h;
177 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->w_expr),
178 var_names, crop->var_values,
179 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
180 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
181 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->h_expr),
182 var_names, crop->var_values,
183 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
184 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = res;
185 /* evaluate again ow as it may depend on oh */
186 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->w_expr),
187 var_names, crop->var_values,
188 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
189 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
190 if (normalize_double(&crop->w, crop->var_values[VAR_OUT_W]) < 0 ||
191 normalize_double(&crop->h, crop->var_values[VAR_OUT_H]) < 0) {
192 av_log(ctx, AV_LOG_ERROR,
193 "Too big value or invalid expression for out_w/ow or out_h/oh. "
194 "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
195 crop->w_expr, crop->h_expr);
196 return AVERROR(EINVAL);
198 crop->w &= ~((1 << crop->hsub) - 1);
199 crop->h &= ~((1 << crop->vsub) - 1);
201 if ((ret = av_expr_parse(&crop->x_pexpr, crop->x_expr, var_names,
202 NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
203 (ret = av_expr_parse(&crop->y_pexpr, crop->y_expr, var_names,
204 NULL, NULL, NULL, NULL, 0, ctx)) < 0)
205 return AVERROR(EINVAL);
207 if (crop->keep_aspect) {
208 AVRational dar = av_mul_q(link->sample_aspect_ratio,
209 (AVRational){ link->w, link->h });
210 av_reduce(&crop->out_sar.num, &crop->out_sar.den,
211 dar.num * crop->h, dar.den * crop->w, INT_MAX);
213 crop->out_sar = link->sample_aspect_ratio;
215 av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d -> w:%d h:%d sar:%d/%d\n",
216 link->w, link->h, link->sample_aspect_ratio.num, link->sample_aspect_ratio.den,
217 crop->w, crop->h, crop->out_sar.num, crop->out_sar.den);
219 if (crop->w <= 0 || crop->h <= 0 ||
220 crop->w > link->w || crop->h > link->h) {
221 av_log(ctx, AV_LOG_ERROR,
222 "Invalid too big or non positive size for width '%d' or height '%d'\n",
224 return AVERROR(EINVAL);
227 /* set default, required in the case the first computed value for x/y is NAN */
228 crop->x = (link->w - crop->w) / 2;
229 crop->y = (link->h - crop->h) / 2;
230 crop->x &= ~((1 << crop->hsub) - 1);
231 crop->y &= ~((1 << crop->vsub) - 1);
235 av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
239 static int config_output(AVFilterLink *link)
241 CropContext *crop = link->src->priv;
245 link->sample_aspect_ratio = crop->out_sar;
250 static int filter_frame(AVFilterLink *link, AVFrame *frame)
252 AVFilterContext *ctx = link->dst;
253 CropContext *crop = ctx->priv;
254 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
257 frame->width = crop->w;
258 frame->height = crop->h;
260 crop->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
261 NAN : frame->pts * av_q2d(link->time_base);
262 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
263 crop->var_values[VAR_Y] = av_expr_eval(crop->y_pexpr, crop->var_values, NULL);
264 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
266 normalize_double(&crop->x, crop->var_values[VAR_X]);
267 normalize_double(&crop->y, crop->var_values[VAR_Y]);
269 if (crop->x < 0) crop->x = 0;
270 if (crop->y < 0) crop->y = 0;
271 if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w;
272 if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h;
273 crop->x &= ~((1 << crop->hsub) - 1);
274 crop->y &= ~((1 << crop->vsub) - 1);
276 av_dlog(ctx, "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n",
277 (int)crop->var_values[VAR_N], crop->var_values[VAR_T], crop->x,
278 crop->y, crop->x+crop->w, crop->y+crop->h);
280 frame->data[0] += crop->y * frame->linesize[0];
281 frame->data[0] += crop->x * crop->max_step[0];
283 if (!(desc->flags & PIX_FMT_PAL || desc->flags & PIX_FMT_PSEUDOPAL)) {
284 for (i = 1; i < 3; i ++) {
285 if (frame->data[i]) {
286 frame->data[i] += (crop->y >> crop->vsub) * frame->linesize[i];
287 frame->data[i] += (crop->x * crop->max_step[i]) >> crop->hsub;
293 if (frame->data[3]) {
294 frame->data[3] += crop->y * frame->linesize[3];
295 frame->data[3] += crop->x * crop->max_step[3];
298 crop->var_values[VAR_N] += 1.0;
300 return ff_filter_frame(link->dst->outputs[0], frame);
303 #define OFFSET(x) offsetof(CropContext, x)
304 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
306 static const AVOption crop_options[] = {
307 { "out_w", "set the width crop area expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
308 { "w", "set the width crop area expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
309 { "out_h", "set the height crop area expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
310 { "h", "set the height crop area expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
311 { "x", "set the x crop area expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "(in_w-out_w)/2"}, CHAR_MIN, CHAR_MAX, FLAGS },
312 { "y", "set the y crop area expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "(in_h-out_h)/2"}, CHAR_MIN, CHAR_MAX, FLAGS },
313 { "keep_aspect", "keep aspect ratio", OFFSET(keep_aspect), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
317 AVFILTER_DEFINE_CLASS(crop);
319 static const AVFilterPad avfilter_vf_crop_inputs[] = {
322 .type = AVMEDIA_TYPE_VIDEO,
323 .filter_frame = filter_frame,
324 .get_video_buffer = ff_null_get_video_buffer,
325 .config_props = config_input,
330 static const AVFilterPad avfilter_vf_crop_outputs[] = {
333 .type = AVMEDIA_TYPE_VIDEO,
334 .config_props = config_output,
339 AVFilter avfilter_vf_crop = {
341 .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."),
343 .priv_size = sizeof(CropContext),
344 .priv_class = &crop_class,
346 .query_formats = query_formats,
349 .inputs = avfilter_vf_crop_inputs,
350 .outputs = avfilter_vf_crop_outputs,