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
80 int x; ///< x offset of the non-cropped area with respect to the input area
81 int y; ///< y offset of the non-cropped area with respect to the input area
82 int w; ///< width of the cropped area
83 int h; ///< height of the cropped area
85 AVRational out_sar; ///< output sample aspect ratio
86 int keep_aspect; ///< keep display aspect ratio when cropping
88 int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
89 int hsub, vsub; ///< chroma subsampling
90 char *x_expr, *y_expr, *w_expr, *h_expr;
91 AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */
92 double var_values[VAR_VARS_NB];
95 static int query_formats(AVFilterContext *ctx)
97 static const enum AVPixelFormat pix_fmts[] = {
98 AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGB48LE,
99 AV_PIX_FMT_BGR48BE, AV_PIX_FMT_BGR48LE,
100 AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA,
101 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA,
102 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
103 AV_PIX_FMT_RGB565BE, AV_PIX_FMT_RGB565LE,
104 AV_PIX_FMT_RGB555BE, AV_PIX_FMT_RGB555LE,
105 AV_PIX_FMT_BGR565BE, AV_PIX_FMT_BGR565LE,
106 AV_PIX_FMT_BGR555BE, AV_PIX_FMT_BGR555LE,
107 AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_GRAY16LE,
108 AV_PIX_FMT_YUV420P16LE, AV_PIX_FMT_YUV420P16BE,
109 AV_PIX_FMT_YUV422P16LE, AV_PIX_FMT_YUV422P16BE,
110 AV_PIX_FMT_YUV444P16LE, AV_PIX_FMT_YUV444P16BE,
111 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,
112 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P,
113 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P,
114 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
115 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ440P,
117 AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8,
118 AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE,
119 AV_PIX_FMT_PAL8, AV_PIX_FMT_GRAY8,
123 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
128 static av_cold void uninit(AVFilterContext *ctx)
130 CropContext *crop = ctx->priv;
132 av_expr_free(crop->x_pexpr); crop->x_pexpr = NULL;
133 av_expr_free(crop->y_pexpr); crop->y_pexpr = NULL;
136 static inline int normalize_double(int *n, double d)
141 ret = AVERROR(EINVAL);
142 } else if (d > INT_MAX || d < INT_MIN) {
143 *n = d > INT_MAX ? INT_MAX : INT_MIN;
144 ret = AVERROR(EINVAL);
151 static int config_input(AVFilterLink *link)
153 AVFilterContext *ctx = link->dst;
154 CropContext *crop = ctx->priv;
155 const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(link->format);
160 crop->var_values[VAR_IN_W] = crop->var_values[VAR_IW] = ctx->inputs[0]->w;
161 crop->var_values[VAR_IN_H] = crop->var_values[VAR_IH] = ctx->inputs[0]->h;
162 crop->var_values[VAR_A] = (float) link->w / link->h;
163 crop->var_values[VAR_SAR] = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
164 crop->var_values[VAR_DAR] = crop->var_values[VAR_A] * crop->var_values[VAR_SAR];
165 crop->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
166 crop->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
167 crop->var_values[VAR_X] = NAN;
168 crop->var_values[VAR_Y] = NAN;
169 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = NAN;
170 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = NAN;
171 crop->var_values[VAR_N] = 0;
172 crop->var_values[VAR_T] = NAN;
173 crop->var_values[VAR_POS] = NAN;
175 av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc);
176 crop->hsub = pix_desc->log2_chroma_w;
177 crop->vsub = pix_desc->log2_chroma_h;
179 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->w_expr),
180 var_names, crop->var_values,
181 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
182 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
183 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->h_expr),
184 var_names, crop->var_values,
185 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
186 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = res;
187 /* evaluate again ow as it may depend on oh */
188 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->w_expr),
189 var_names, crop->var_values,
190 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
191 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
192 if (normalize_double(&crop->w, crop->var_values[VAR_OUT_W]) < 0 ||
193 normalize_double(&crop->h, crop->var_values[VAR_OUT_H]) < 0) {
194 av_log(ctx, AV_LOG_ERROR,
195 "Too big value or invalid expression for out_w/ow or out_h/oh. "
196 "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
197 crop->w_expr, crop->h_expr);
198 return AVERROR(EINVAL);
200 crop->w &= ~((1 << crop->hsub) - 1);
201 crop->h &= ~((1 << crop->vsub) - 1);
203 if ((ret = av_expr_parse(&crop->x_pexpr, crop->x_expr, var_names,
204 NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
205 (ret = av_expr_parse(&crop->y_pexpr, crop->y_expr, var_names,
206 NULL, NULL, NULL, NULL, 0, ctx)) < 0)
207 return AVERROR(EINVAL);
209 if (crop->keep_aspect) {
210 AVRational dar = av_mul_q(link->sample_aspect_ratio,
211 (AVRational){ link->w, link->h });
212 av_reduce(&crop->out_sar.num, &crop->out_sar.den,
213 dar.num * crop->h, dar.den * crop->w, INT_MAX);
215 crop->out_sar = link->sample_aspect_ratio;
217 av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d -> w:%d h:%d sar:%d/%d\n",
218 link->w, link->h, link->sample_aspect_ratio.num, link->sample_aspect_ratio.den,
219 crop->w, crop->h, crop->out_sar.num, crop->out_sar.den);
221 if (crop->w <= 0 || crop->h <= 0 ||
222 crop->w > link->w || crop->h > link->h) {
223 av_log(ctx, AV_LOG_ERROR,
224 "Invalid too big or non positive size for width '%d' or height '%d'\n",
226 return AVERROR(EINVAL);
229 /* set default, required in the case the first computed value for x/y is NAN */
230 crop->x = (link->w - crop->w) / 2;
231 crop->y = (link->h - crop->h) / 2;
232 crop->x &= ~((1 << crop->hsub) - 1);
233 crop->y &= ~((1 << crop->vsub) - 1);
237 av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
241 static int config_output(AVFilterLink *link)
243 CropContext *crop = link->src->priv;
247 link->sample_aspect_ratio = crop->out_sar;
252 static int filter_frame(AVFilterLink *link, AVFrame *frame)
254 AVFilterContext *ctx = link->dst;
255 CropContext *crop = ctx->priv;
256 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
259 frame->width = crop->w;
260 frame->height = crop->h;
262 crop->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
263 NAN : frame->pts * av_q2d(link->time_base);
264 crop->var_values[VAR_POS] = av_frame_get_pkt_pos(frame) == -1 ?
265 NAN : av_frame_get_pkt_pos(frame);
266 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
267 crop->var_values[VAR_Y] = av_expr_eval(crop->y_pexpr, crop->var_values, NULL);
268 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
270 normalize_double(&crop->x, crop->var_values[VAR_X]);
271 normalize_double(&crop->y, crop->var_values[VAR_Y]);
273 if (crop->x < 0) crop->x = 0;
274 if (crop->y < 0) crop->y = 0;
275 if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w;
276 if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h;
277 crop->x &= ~((1 << crop->hsub) - 1);
278 crop->y &= ~((1 << crop->vsub) - 1);
280 av_dlog(ctx, "n:%d t:%f pos:%f x:%d y:%d x+w:%d y+h:%d\n",
281 (int)crop->var_values[VAR_N], crop->var_values[VAR_T], crop->var_values[VAR_POS],
282 crop->x, crop->y, crop->x+crop->w, crop->y+crop->h);
284 frame->data[0] += crop->y * frame->linesize[0];
285 frame->data[0] += crop->x * crop->max_step[0];
287 if (!(desc->flags & PIX_FMT_PAL || desc->flags & PIX_FMT_PSEUDOPAL)) {
288 for (i = 1; i < 3; i ++) {
289 if (frame->data[i]) {
290 frame->data[i] += (crop->y >> crop->vsub) * frame->linesize[i];
291 frame->data[i] += (crop->x * crop->max_step[i]) >> crop->hsub;
297 if (frame->data[3]) {
298 frame->data[3] += crop->y * frame->linesize[3];
299 frame->data[3] += crop->x * crop->max_step[3];
302 crop->var_values[VAR_N] += 1.0;
304 return ff_filter_frame(link->dst->outputs[0], frame);
307 #define OFFSET(x) offsetof(CropContext, x)
308 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
310 static const AVOption crop_options[] = {
311 { "out_w", "set the width crop area expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
312 { "w", "set the width crop area expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
313 { "out_h", "set the height crop area expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
314 { "h", "set the height crop area expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
315 { "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 },
316 { "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 },
317 { "keep_aspect", "keep aspect ratio", OFFSET(keep_aspect), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
321 AVFILTER_DEFINE_CLASS(crop);
323 static const AVFilterPad avfilter_vf_crop_inputs[] = {
326 .type = AVMEDIA_TYPE_VIDEO,
327 .filter_frame = filter_frame,
328 .get_video_buffer = ff_null_get_video_buffer,
329 .config_props = config_input,
334 static const AVFilterPad avfilter_vf_crop_outputs[] = {
337 .type = AVMEDIA_TYPE_VIDEO,
338 .config_props = config_output,
343 AVFilter avfilter_vf_crop = {
345 .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."),
347 .priv_size = sizeof(CropContext),
348 .priv_class = &crop_class,
350 .query_formats = query_formats,
353 .inputs = avfilter_vf_crop_inputs,
354 .outputs = avfilter_vf_crop_outputs,