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 int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes
78 int hsub, vsub; ///< chroma subsampling
79 char x_expr[256], y_expr[256], ow_expr[256], oh_expr[256];
80 AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */
81 double var_values[VAR_VARS_NB];
84 static int query_formats(AVFilterContext *ctx)
86 static const enum PixelFormat pix_fmts[] = {
87 PIX_FMT_RGB48BE, PIX_FMT_RGB48LE,
88 PIX_FMT_BGR48BE, PIX_FMT_BGR48LE,
89 PIX_FMT_ARGB, PIX_FMT_RGBA,
90 PIX_FMT_ABGR, PIX_FMT_BGRA,
91 PIX_FMT_RGB24, PIX_FMT_BGR24,
92 PIX_FMT_RGB565BE, PIX_FMT_RGB565LE,
93 PIX_FMT_RGB555BE, PIX_FMT_RGB555LE,
94 PIX_FMT_BGR565BE, PIX_FMT_BGR565LE,
95 PIX_FMT_BGR555BE, PIX_FMT_BGR555LE,
96 PIX_FMT_GRAY16BE, PIX_FMT_GRAY16LE,
97 PIX_FMT_YUV420P16LE, PIX_FMT_YUV420P16BE,
98 PIX_FMT_YUV422P16LE, PIX_FMT_YUV422P16BE,
99 PIX_FMT_YUV444P16LE, PIX_FMT_YUV444P16BE,
100 PIX_FMT_YUV444P, PIX_FMT_YUV422P,
101 PIX_FMT_YUV420P, PIX_FMT_YUV411P,
102 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
103 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P,
104 PIX_FMT_YUVJ420P, PIX_FMT_YUVJ440P,
106 PIX_FMT_RGB8, PIX_FMT_BGR8,
107 PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE,
108 PIX_FMT_PAL8, PIX_FMT_GRAY8,
112 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
117 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
119 CropContext *crop = ctx->priv;
121 av_strlcpy(crop->ow_expr, "iw", sizeof(crop->ow_expr));
122 av_strlcpy(crop->oh_expr, "ih", sizeof(crop->oh_expr));
123 av_strlcpy(crop->x_expr, "(in_w-out_w)/2", sizeof(crop->x_expr));
124 av_strlcpy(crop->y_expr, "(in_h-out_h)/2", sizeof(crop->y_expr));
127 sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]", crop->ow_expr, crop->oh_expr, crop->x_expr, crop->y_expr);
132 static av_cold void uninit(AVFilterContext *ctx)
134 CropContext *crop = ctx->priv;
136 av_expr_free(crop->x_pexpr); crop->x_pexpr = NULL;
137 av_expr_free(crop->y_pexpr); crop->y_pexpr = NULL;
140 static inline int normalize_double(int *n, double d)
145 ret = AVERROR(EINVAL);
146 } else if (d > INT_MAX || d < INT_MIN) {
147 *n = d > INT_MAX ? INT_MAX : INT_MIN;
148 ret = AVERROR(EINVAL);
155 static int config_input(AVFilterLink *link)
157 AVFilterContext *ctx = link->dst;
158 CropContext *crop = ctx->priv;
159 const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[link->format];
164 crop->var_values[VAR_IN_W] = crop->var_values[VAR_IW] = ctx->inputs[0]->w;
165 crop->var_values[VAR_IN_H] = crop->var_values[VAR_IH] = ctx->inputs[0]->h;
166 crop->var_values[VAR_A] = (float) link->w / link->h;
167 crop->var_values[VAR_SAR] = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
168 crop->var_values[VAR_DAR] = crop->var_values[VAR_A] * crop->var_values[VAR_SAR];
169 crop->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
170 crop->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
171 crop->var_values[VAR_X] = NAN;
172 crop->var_values[VAR_Y] = NAN;
173 crop->var_values[VAR_OUT_W] = crop->var_values[VAR_OW] = NAN;
174 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = NAN;
175 crop->var_values[VAR_N] = 0;
176 crop->var_values[VAR_T] = NAN;
177 crop->var_values[VAR_POS] = NAN;
179 av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc);
180 crop->hsub = av_pix_fmt_descriptors[link->format].log2_chroma_w;
181 crop->vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;
183 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->ow_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_W] = crop->var_values[VAR_OW] = res;
187 if ((ret = av_expr_parse_and_eval(&res, (expr = crop->oh_expr),
188 var_names, crop->var_values,
189 NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr;
190 crop->var_values[VAR_OUT_H] = crop->var_values[VAR_OH] = res;
191 /* evaluate again ow as it may depend on oh */
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 (normalize_double(&crop->w, crop->var_values[VAR_OUT_W]) < 0 ||
197 normalize_double(&crop->h, crop->var_values[VAR_OUT_H]) < 0) {
198 av_log(ctx, AV_LOG_ERROR,
199 "Too big value or invalid expression for out_w/ow or out_h/oh. "
200 "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
201 crop->ow_expr, crop->oh_expr);
202 return AVERROR(EINVAL);
204 crop->w &= ~((1 << crop->hsub) - 1);
205 crop->h &= ~((1 << crop->vsub) - 1);
207 if ((ret = av_expr_parse(&crop->x_pexpr, crop->x_expr, var_names,
208 NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
209 (ret = av_expr_parse(&crop->y_pexpr, crop->y_expr, var_names,
210 NULL, NULL, NULL, NULL, 0, ctx)) < 0)
211 return AVERROR(EINVAL);
213 av_log(ctx, AV_LOG_INFO, "w:%d h:%d -> w:%d h:%d\n",
214 link->w, link->h, crop->w, crop->h);
216 if (crop->w <= 0 || crop->h <= 0 ||
217 crop->w > link->w || crop->h > link->h) {
218 av_log(ctx, AV_LOG_ERROR,
219 "Invalid too big or non positive size for width '%d' or height '%d'\n",
221 return AVERROR(EINVAL);
224 /* set default, required in the case the first computed value for x/y is NAN */
225 crop->x = (link->w - crop->w) / 2;
226 crop->y = (link->h - crop->h) / 2;
227 crop->x &= ~((1 << crop->hsub) - 1);
228 crop->y &= ~((1 << crop->vsub) - 1);
232 av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
236 static int config_output(AVFilterLink *link)
238 CropContext *crop = link->src->priv;
246 static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
248 AVFilterContext *ctx = link->dst;
249 CropContext *crop = ctx->priv;
250 AVFilterBufferRef *ref2;
253 ref2 = avfilter_ref_buffer(picref, ~0);
254 ref2->video->w = crop->w;
255 ref2->video->h = crop->h;
257 crop->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
258 NAN : picref->pts * av_q2d(link->time_base);
259 crop->var_values[VAR_POS] = picref->pos == -1 ? NAN : picref->pos;
260 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
261 crop->var_values[VAR_Y] = av_expr_eval(crop->y_pexpr, crop->var_values, NULL);
262 crop->var_values[VAR_X] = av_expr_eval(crop->x_pexpr, crop->var_values, NULL);
264 normalize_double(&crop->x, crop->var_values[VAR_X]);
265 normalize_double(&crop->y, crop->var_values[VAR_Y]);
267 if (crop->x < 0) crop->x = 0;
268 if (crop->y < 0) crop->y = 0;
269 if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w;
270 if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h;
271 crop->x &= ~((1 << crop->hsub) - 1);
272 crop->y &= ~((1 << crop->vsub) - 1);
274 av_dlog(ctx, "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n",
275 (int)crop->var_values[VAR_N], crop->var_values[VAR_T], crop->x,
276 crop->y, crop->x+crop->w, crop->y+crop->h);
278 ref2->data[0] += crop->y * ref2->linesize[0];
279 ref2->data[0] += crop->x * crop->max_step[0];
281 if (!(av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PAL)) {
282 for (i = 1; i < 3; i ++) {
284 ref2->data[i] += (crop->y >> crop->vsub) * ref2->linesize[i];
285 ref2->data[i] += (crop->x * crop->max_step[i]) >> crop->hsub;
292 ref2->data[3] += crop->y * ref2->linesize[3];
293 ref2->data[3] += crop->x * crop->max_step[3];
296 avfilter_start_frame(link->dst->outputs[0], ref2);
299 static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
301 AVFilterContext *ctx = link->dst;
302 CropContext *crop = ctx->priv;
304 if (y >= crop->y + crop->h || y + h <= crop->y)
311 if (y + h > crop->y + crop->h)
312 h = crop->y + crop->h - y;
314 avfilter_draw_slice(ctx->outputs[0], y - crop->y, h, slice_dir);
317 static void end_frame(AVFilterLink *link)
319 CropContext *crop = link->dst->priv;
321 crop->var_values[VAR_N] += 1.0;
322 avfilter_unref_buffer(link->cur_buf);
323 avfilter_end_frame(link->dst->outputs[0]);
326 AVFilter avfilter_vf_crop = {
328 .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."),
330 .priv_size = sizeof(CropContext),
332 .query_formats = query_formats,
336 .inputs = (const AVFilterPad[]) {{ .name = "default",
337 .type = AVMEDIA_TYPE_VIDEO,
338 .start_frame = start_frame,
339 .draw_slice = draw_slice,
340 .end_frame = end_frame,
341 .get_video_buffer = avfilter_null_get_video_buffer,
342 .config_props = config_input, },
344 .outputs = (const AVFilterPad[]) {{ .name = "default",
345 .type = AVMEDIA_TYPE_VIDEO,
346 .config_props = config_output, },