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
29 #include "libavutil/eval.h"
30 #include "libavutil/avstring.h"
31 #include "libavutil/libm.h"
32 #include "libavutil/imgutils.h"
33 #include "libavutil/mathematics.h"
35 static const char *const var_names[] = {
36 "in_w", "iw", ///< width of the input video
37 "in_h", "ih", ///< height of the input video
38 "out_w", "ow", ///< width of the cropped video
39 "out_h", "oh", ///< height of the cropped video
47 "n", ///< number of frame
48 "pos", ///< position in the file
49 "t", ///< timestamp expressed in seconds
72 int x; ///< x offset of the non-cropped area with respect to the input area
73 int y; ///< y offset of the non-cropped area with respect to the input area
74 int w; ///< width of the cropped area
75 int h; ///< height of the cropped area
77 AVRational out_sar; ///< output sample aspect ratio
78 int keep_aspect; ///< keep display aspect ratio when cropping
80 int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
81 int hsub, vsub; ///< chroma subsampling
82 char x_expr[256], y_expr[256], ow_expr[256], oh_expr[256];
83 AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */
84 double var_values[VAR_VARS_NB];
87 static int query_formats(AVFilterContext *ctx)
89 static const enum PixelFormat pix_fmts[] = {
90 PIX_FMT_RGB48BE, PIX_FMT_RGB48LE,
91 PIX_FMT_BGR48BE, PIX_FMT_BGR48LE,
92 PIX_FMT_ARGB, PIX_FMT_RGBA,
93 PIX_FMT_ABGR, PIX_FMT_BGRA,
94 PIX_FMT_RGB24, PIX_FMT_BGR24,
95 PIX_FMT_RGB565BE, PIX_FMT_RGB565LE,
96 PIX_FMT_RGB555BE, PIX_FMT_RGB555LE,
97 PIX_FMT_BGR565BE, PIX_FMT_BGR565LE,
98 PIX_FMT_BGR555BE, PIX_FMT_BGR555LE,
99 PIX_FMT_GRAY16BE, PIX_FMT_GRAY16LE,
100 PIX_FMT_YUV420P16LE, PIX_FMT_YUV420P16BE,
101 PIX_FMT_YUV422P16LE, PIX_FMT_YUV422P16BE,
102 PIX_FMT_YUV444P16LE, PIX_FMT_YUV444P16BE,
103 PIX_FMT_YUV444P, PIX_FMT_YUV422P,
104 PIX_FMT_YUV420P, PIX_FMT_YUV411P,
105 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
106 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P,
107 PIX_FMT_YUVJ420P, PIX_FMT_YUVJ440P,
109 PIX_FMT_RGB8, PIX_FMT_BGR8,
110 PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE,
111 PIX_FMT_PAL8, PIX_FMT_GRAY8,
115 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
120 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
122 CropContext *crop = ctx->priv;
124 av_strlcpy(crop->ow_expr, "iw", sizeof(crop->ow_expr));
125 av_strlcpy(crop->oh_expr, "ih", sizeof(crop->oh_expr));
126 av_strlcpy(crop->x_expr, "(in_w-out_w)/2", sizeof(crop->x_expr));
127 av_strlcpy(crop->y_expr, "(in_h-out_h)/2", sizeof(crop->y_expr));
130 sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]:%d", crop->ow_expr, crop->oh_expr, crop->x_expr, crop->y_expr, &crop->keep_aspect);
135 static av_cold void uninit(AVFilterContext *ctx)
137 CropContext *crop = ctx->priv;
139 av_expr_free(crop->x_pexpr); crop->x_pexpr = NULL;
140 av_expr_free(crop->y_pexpr); crop->y_pexpr = NULL;
143 static inline int normalize_double(int *n, double d)
148 ret = AVERROR(EINVAL);
149 } else if (d > INT_MAX || d < INT_MIN) {
150 *n = d > INT_MAX ? INT_MAX : INT_MIN;
151 ret = AVERROR(EINVAL);
158 static int config_input(AVFilterLink *link)
160 AVFilterContext *ctx = link->dst;
161 CropContext *crop = ctx->priv;
162 const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[link->format];
167 crop->var_values[VAR_IN_W] = crop->var_values[VAR_IW] = ctx->inputs[0]->w;
168 crop->var_values[VAR_IN_H] = crop->var_values[VAR_IH] = ctx->inputs[0]->h;
169 crop->var_values[VAR_A] = (float) link->w / link->h;
170 crop->var_values[VAR_SAR] = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
171 crop->var_values[VAR_DAR] = crop->var_values[VAR_A] * crop->var_values[VAR_SAR];
172 crop->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
173 crop->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
174 crop->var_values[VAR_X] = NAN;
175 crop->var_values[VAR_Y] = NAN;
176 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = NAN;
177 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = NAN;
178 crop->var_values[VAR_N] = 0;
179 crop->var_values[VAR_T] = NAN;
180 crop->var_values[VAR_POS] = NAN;
182 av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc);
183 crop->hsub = av_pix_fmt_descriptors[link->format].log2_chroma_w;
184 crop->vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;
186 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->ow_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 ((ret = av_expr_parse_and_eval(&res, (expr = crop->oh_expr),
191 var_names, crop->var_values,
192 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
193 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = res;
194 /* evaluate again ow as it may depend on oh */
195 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->ow_expr),
196 var_names, crop->var_values,
197 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
198 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = res;
199 if (normalize_double(&crop->w, crop->var_values[VAR_OUT_W]) < 0 ||
200 normalize_double(&crop->h, crop->var_values[VAR_OUT_H]) < 0) {
201 av_log(ctx, AV_LOG_ERROR,
202 "Too big value or invalid expression for out_w/ow or out_h/oh. "
203 "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
204 crop->ow_expr, crop->oh_expr);
205 return AVERROR(EINVAL);
207 crop->w &= ~((1 << crop->hsub) - 1);
208 crop->h &= ~((1 << crop->vsub) - 1);
210 if ((ret = av_expr_parse(&crop->x_pexpr, crop->x_expr, var_names,
211 NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
212 (ret = av_expr_parse(&crop->y_pexpr, crop->y_expr, var_names,
213 NULL, NULL, NULL, NULL, 0, ctx)) < 0)
214 return AVERROR(EINVAL);
216 if (crop->keep_aspect) {
217 AVRational dar = av_mul_q(link->sample_aspect_ratio,
218 (AVRational){ link->w, link->h });
219 av_reduce(&crop->out_sar.num, &crop->out_sar.den,
220 dar.num * crop->h, dar.den * crop->w, INT_MAX);
222 crop->out_sar = link->sample_aspect_ratio;
224 av_log(ctx, AV_LOG_INFO, "w:%d h:%d sar:%d/%d -> w:%d h:%d sar:%d/%d\n",
225 link->w, link->h, link->sample_aspect_ratio.num, link->sample_aspect_ratio.den,
226 crop->w, crop->h, crop->out_sar.num, crop->out_sar.den);
228 if (crop->w <= 0 || crop->h <= 0 ||
229 crop->w > link->w || crop->h > link->h) {
230 av_log(ctx, AV_LOG_ERROR,
231 "Invalid too big or non positive size for width '%d' or height '%d'\n",
233 return AVERROR(EINVAL);
236 /* set default, required in the case the first computed value for x/y is NAN */
237 crop->x = (link->w - crop->w) / 2;
238 crop->y = (link->h - crop->h) / 2;
239 crop->x &= ~((1 << crop->hsub) - 1);
240 crop->y &= ~((1 << crop->vsub) - 1);
244 av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
248 static int config_output(AVFilterLink *link)
250 CropContext *crop = link->src->priv;
254 link->sample_aspect_ratio = crop->out_sar;
259 static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
261 AVFilterContext *ctx = link->dst;
262 CropContext *crop = ctx->priv;
263 AVFilterBufferRef *ref2;
266 ref2 = avfilter_ref_buffer(picref, ~0);
267 ref2->video->w = crop->w;
268 ref2->video->h = crop->h;
270 crop->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
271 NAN : picref->pts * av_q2d(link->time_base);
272 crop->var_values[VAR_POS] = picref->pos == -1 ? NAN : picref->pos;
273 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
274 crop->var_values[VAR_Y] = av_expr_eval(crop->y_pexpr, crop->var_values, NULL);
275 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
277 normalize_double(&crop->x, crop->var_values[VAR_X]);
278 normalize_double(&crop->y, crop->var_values[VAR_Y]);
280 if (crop->x < 0) crop->x = 0;
281 if (crop->y < 0) crop->y = 0;
282 if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w;
283 if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h;
284 crop->x &= ~((1 << crop->hsub) - 1);
285 crop->y &= ~((1 << crop->vsub) - 1);
287 av_dlog(ctx, "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n",
288 (int)crop->var_values[VAR_N], crop->var_values[VAR_T], crop->x,
289 crop->y, crop->x+crop->w, crop->y+crop->h);
291 ref2->data[0] += crop->y * ref2->linesize[0];
292 ref2->data[0] += crop->x * crop->max_step[0];
294 if (!(av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PAL ||
295 av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PSEUDOPAL)) {
296 for (i = 1; i < 3; i ++) {
298 ref2->data[i] += (crop->y >> crop->vsub) * ref2->linesize[i];
299 ref2->data[i] += (crop->x * crop->max_step[i]) >> crop->hsub;
306 ref2->data[3] += crop->y * ref2->linesize[3];
307 ref2->data[3] += crop->x * crop->max_step[3];
310 avfilter_start_frame(link->dst->outputs[0], ref2);
313 static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
315 AVFilterContext *ctx = link->dst;
316 CropContext *crop = ctx->priv;
318 if (y >= crop->y + crop->h || y + h <= crop->y)
325 if (y + h > crop->y + crop->h)
326 h = crop->y + crop->h - y;
328 avfilter_draw_slice(ctx->outputs[0], y - crop->y, h, slice_dir);
331 static void end_frame(AVFilterLink *link)
333 CropContext *crop = link->dst->priv;
335 crop->var_values[VAR_N] += 1.0;
336 avfilter_unref_buffer(link->cur_buf);
337 avfilter_end_frame(link->dst->outputs[0]);
340 AVFilter avfilter_vf_crop = {
342 .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."),
344 .priv_size = sizeof(CropContext),
346 .query_formats = query_formats,
350 .inputs = (const AVFilterPad[]) {{ .name = "default",
351 .type = AVMEDIA_TYPE_VIDEO,
352 .start_frame = start_frame,
353 .draw_slice = draw_slice,
354 .end_frame = end_frame,
355 .get_video_buffer = avfilter_null_get_video_buffer,
356 .config_props = config_input, },
358 .outputs = (const AVFilterPad[]) {{ .name = "default",
359 .type = AVMEDIA_TYPE_VIDEO,
360 .config_props = config_output, },