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"
41 static const char *const var_names[] = {
42 "in_w", "iw", ///< width of the input video
43 "in_h", "ih", ///< height of the input video
44 "out_w", "ow", ///< width of the cropped video
45 "out_h", "oh", ///< height of the cropped video
53 "n", ///< number of frame
54 "pos", ///< position in the file
55 "t", ///< timestamp expressed in seconds
78 int x; ///< x offset of the non-cropped area with respect to the input area
79 int y; ///< y offset of the non-cropped area with respect to the input area
80 int w; ///< width of the cropped area
81 int h; ///< height of the cropped area
83 AVRational out_sar; ///< output sample aspect ratio
84 int keep_aspect; ///< keep display aspect ratio when cropping
86 int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
87 int hsub, vsub; ///< chroma subsampling
88 char x_expr[256], y_expr[256], ow_expr[256], oh_expr[256];
89 AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */
90 double var_values[VAR_VARS_NB];
93 static int query_formats(AVFilterContext *ctx)
95 static const enum AVPixelFormat pix_fmts[] = {
96 AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGB48LE,
97 AV_PIX_FMT_BGR48BE, AV_PIX_FMT_BGR48LE,
98 AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA,
99 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA,
100 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
101 AV_PIX_FMT_RGB565BE, AV_PIX_FMT_RGB565LE,
102 AV_PIX_FMT_RGB555BE, AV_PIX_FMT_RGB555LE,
103 AV_PIX_FMT_BGR565BE, AV_PIX_FMT_BGR565LE,
104 AV_PIX_FMT_BGR555BE, AV_PIX_FMT_BGR555LE,
105 AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_GRAY16LE,
106 AV_PIX_FMT_YUV420P16LE, AV_PIX_FMT_YUV420P16BE,
107 AV_PIX_FMT_YUV422P16LE, AV_PIX_FMT_YUV422P16BE,
108 AV_PIX_FMT_YUV444P16LE, AV_PIX_FMT_YUV444P16BE,
109 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,
110 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P,
111 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P,
112 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
113 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ440P,
115 AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8,
116 AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE,
117 AV_PIX_FMT_PAL8, AV_PIX_FMT_GRAY8,
121 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
126 static av_cold int init(AVFilterContext *ctx, const char *args)
128 CropContext *crop = ctx->priv;
130 av_strlcpy(crop->ow_expr, "iw", sizeof(crop->ow_expr));
131 av_strlcpy(crop->oh_expr, "ih", sizeof(crop->oh_expr));
132 av_strlcpy(crop->x_expr, "(in_w-out_w)/2", sizeof(crop->x_expr));
133 av_strlcpy(crop->y_expr, "(in_h-out_h)/2", sizeof(crop->y_expr));
136 sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]:%d", crop->ow_expr, crop->oh_expr, crop->x_expr, crop->y_expr, &crop->keep_aspect);
141 static av_cold void uninit(AVFilterContext *ctx)
143 CropContext *crop = ctx->priv;
145 av_expr_free(crop->x_pexpr); crop->x_pexpr = NULL;
146 av_expr_free(crop->y_pexpr); crop->y_pexpr = NULL;
149 static inline int normalize_double(int *n, double d)
154 ret = AVERROR(EINVAL);
155 } else if (d > INT_MAX || d < INT_MIN) {
156 *n = d > INT_MAX ? INT_MAX : INT_MIN;
157 ret = AVERROR(EINVAL);
164 static int config_input(AVFilterLink *link)
166 AVFilterContext *ctx = link->dst;
167 CropContext *crop = ctx->priv;
168 const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(link->format);
173 crop->var_values[VAR_IN_W] = crop->var_values[VAR_IW] = ctx->inputs[0]->w;
174 crop->var_values[VAR_IN_H] = crop->var_values[VAR_IH] = ctx->inputs[0]->h;
175 crop->var_values[VAR_A] = (float) link->w / link->h;
176 crop->var_values[VAR_SAR] = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
177 crop->var_values[VAR_DAR] = crop->var_values[VAR_A] * crop->var_values[VAR_SAR];
178 crop->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
179 crop->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
180 crop->var_values[VAR_X] = NAN;
181 crop->var_values[VAR_Y] = NAN;
182 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = NAN;
183 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = NAN;
184 crop->var_values[VAR_N] = 0;
185 crop->var_values[VAR_T] = NAN;
186 crop->var_values[VAR_POS] = NAN;
188 av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc);
189 crop->hsub = pix_desc->log2_chroma_w;
190 crop->vsub = pix_desc->log2_chroma_h;
192 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->ow_expr),
193 var_names, crop->var_values,
194 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
195 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
196 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->oh_expr),
197 var_names, crop->var_values,
198 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
199 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = res;
200 /* evaluate again ow as it may depend on oh */
201 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->ow_expr),
202 var_names, crop->var_values,
203 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
204 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
205 if (normalize_double(&crop->w, crop->var_values[VAR_OUT_W]) < 0 ||
206 normalize_double(&crop->h, crop->var_values[VAR_OUT_H]) < 0) {
207 av_log(ctx, AV_LOG_ERROR,
208 "Too big value or invalid expression for out_w/ow or out_h/oh. "
209 "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
210 crop->ow_expr, crop->oh_expr);
211 return AVERROR(EINVAL);
213 crop->w &= ~((1 << crop->hsub) - 1);
214 crop->h &= ~((1 << crop->vsub) - 1);
216 if ((ret = av_expr_parse(&crop->x_pexpr, crop->x_expr, var_names,
217 NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
218 (ret = av_expr_parse(&crop->y_pexpr, crop->y_expr, var_names,
219 NULL, NULL, NULL, NULL, 0, ctx)) < 0)
220 return AVERROR(EINVAL);
222 if (crop->keep_aspect) {
223 AVRational dar = av_mul_q(link->sample_aspect_ratio,
224 (AVRational){ link->w, link->h });
225 av_reduce(&crop->out_sar.num, &crop->out_sar.den,
226 dar.num * crop->h, dar.den * crop->w, INT_MAX);
228 crop->out_sar = link->sample_aspect_ratio;
230 av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d -> w:%d h:%d sar:%d/%d\n",
231 link->w, link->h, link->sample_aspect_ratio.num, link->sample_aspect_ratio.den,
232 crop->w, crop->h, crop->out_sar.num, crop->out_sar.den);
234 if (crop->w <= 0 || crop->h <= 0 ||
235 crop->w > link->w || crop->h > link->h) {
236 av_log(ctx, AV_LOG_ERROR,
237 "Invalid too big or non positive size for width '%d' or height '%d'\n",
239 return AVERROR(EINVAL);
242 /* set default, required in the case the first computed value for x/y is NAN */
243 crop->x = (link->w - crop->w) / 2;
244 crop->y = (link->h - crop->h) / 2;
245 crop->x &= ~((1 << crop->hsub) - 1);
246 crop->y &= ~((1 << crop->vsub) - 1);
250 av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
254 static int config_output(AVFilterLink *link)
256 CropContext *crop = link->src->priv;
260 link->sample_aspect_ratio = crop->out_sar;
265 static int start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
267 AVFilterContext *ctx = link->dst;
268 CropContext *crop = ctx->priv;
269 AVFilterBufferRef *ref2;
270 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
273 ref2 = avfilter_ref_buffer(picref, ~0);
275 return AVERROR(ENOMEM);
277 ref2->video->w = crop->w;
278 ref2->video->h = crop->h;
280 crop->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
281 NAN : picref->pts * av_q2d(link->time_base);
282 crop->var_values[VAR_POS] = picref->pos == -1 ? NAN : picref->pos;
283 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
284 crop->var_values[VAR_Y] = av_expr_eval(crop->y_pexpr, crop->var_values, NULL);
285 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
287 normalize_double(&crop->x, crop->var_values[VAR_X]);
288 normalize_double(&crop->y, crop->var_values[VAR_Y]);
290 if (crop->x < 0) crop->x = 0;
291 if (crop->y < 0) crop->y = 0;
292 if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w;
293 if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h;
294 crop->x &= ~((1 << crop->hsub) - 1);
295 crop->y &= ~((1 << crop->vsub) - 1);
297 av_dlog(ctx, "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n",
298 (int)crop->var_values[VAR_N], crop->var_values[VAR_T], crop->x,
299 crop->y, crop->x+crop->w, crop->y+crop->h);
301 ref2->data[0] += crop->y * ref2->linesize[0];
302 ref2->data[0] += crop->x * crop->max_step[0];
304 if (!(desc->flags & PIX_FMT_PAL || desc->flags & PIX_FMT_PSEUDOPAL)) {
305 for (i = 1; i < 3; i ++) {
307 ref2->data[i] += (crop->y >> crop->vsub) * ref2->linesize[i];
308 ref2->data[i] += (crop->x * crop->max_step[i]) >> crop->hsub;
315 ref2->data[3] += crop->y * ref2->linesize[3];
316 ref2->data[3] += crop->x * crop->max_step[3];
319 return ff_start_frame(link->dst->outputs[0], ref2);
322 static int draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
324 AVFilterContext *ctx = link->dst;
325 CropContext *crop = ctx->priv;
327 if (y >= crop->y + crop->h || y + h <= crop->y)
334 if (y + h > crop->y + crop->h)
335 h = crop->y + crop->h - y;
337 return ff_draw_slice(ctx->outputs[0], y - crop->y, h, slice_dir);
340 static int end_frame(AVFilterLink *link)
342 CropContext *crop = link->dst->priv;
344 crop->var_values[VAR_N] += 1.0;
345 return ff_end_frame(link->dst->outputs[0]);
348 static const AVFilterPad avfilter_vf_crop_inputs[] = {
351 .type = AVMEDIA_TYPE_VIDEO,
352 .start_frame = start_frame,
353 .draw_slice = draw_slice,
354 .end_frame = end_frame,
355 .get_video_buffer = ff_null_get_video_buffer,
356 .config_props = config_input,
361 static const AVFilterPad avfilter_vf_crop_outputs[] = {
364 .type = AVMEDIA_TYPE_VIDEO,
365 .config_props = config_output,
370 AVFilter avfilter_vf_crop = {
372 .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."),
374 .priv_size = sizeof(CropContext),
376 .query_formats = query_formats,
380 .inputs = avfilter_vf_crop_inputs,
381 .outputs = avfilter_vf_crop_outputs,