More accurate value for log2(10)
[libav.git] / libavfilter / vf_crop.c
1 /*
2 * copyright (c) 2007 Bobby Bingham
3 *
4 * This file is part of FFmpeg.
5 *
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.
10 *
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.
15 *
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
19 */
20
21 /**
22 * @file libavfilter/vf_crop.c
23 * video crop filter
24 */
25
26 #include "avfilter.h"
27 #include "libavutil/pixdesc.h"
28
29 typedef struct {
30 int x; ///< x offset of the non-cropped area with respect to the input area
31 int y; ///< y offset of the non-cropped area with respect to the input area
32 int w; ///< width of the cropped area
33 int h; ///< height of the cropped area
34
35 int bpp; ///< bits per pixel
36 int hsub, vsub; ///< chroma subsampling
37 } CropContext;
38
39 static int query_formats(AVFilterContext *ctx)
40 {
41 static const enum PixelFormat pix_fmts[] = {
42 PIX_FMT_RGB48BE, PIX_FMT_RGB48LE,
43 PIX_FMT_ARGB, PIX_FMT_RGBA,
44 PIX_FMT_ABGR, PIX_FMT_BGRA,
45 PIX_FMT_RGB24, PIX_FMT_BGR24,
46 PIX_FMT_RGB565BE, PIX_FMT_RGB565LE,
47 PIX_FMT_RGB555BE, PIX_FMT_RGB555LE,
48 PIX_FMT_BGR565BE, PIX_FMT_BGR565LE,
49 PIX_FMT_BGR555BE, PIX_FMT_BGR555LE,
50 PIX_FMT_GRAY16BE, PIX_FMT_GRAY16LE,
51 PIX_FMT_YUV420P16LE, PIX_FMT_YUV420P16BE,
52 PIX_FMT_YUV422P16LE, PIX_FMT_YUV422P16BE,
53 PIX_FMT_YUV444P16LE, PIX_FMT_YUV444P16BE,
54 PIX_FMT_YUV444P, PIX_FMT_YUV422P,
55 PIX_FMT_YUV420P, PIX_FMT_YUV411P,
56 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
57 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P,
58 PIX_FMT_YUVJ420P, PIX_FMT_YUVJ440P,
59 PIX_FMT_YUVA420P,
60 PIX_FMT_RGB8, PIX_FMT_BGR8,
61 PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE,
62 PIX_FMT_PAL8, PIX_FMT_GRAY8,
63 PIX_FMT_NONE
64 };
65
66 avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
67
68 return 0;
69 }
70
71 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
72 {
73 CropContext *crop = ctx->priv;
74
75 if (args)
76 sscanf(args, "%d:%d:%d:%d", &crop->x, &crop->y, &crop->w, &crop->h);
77
78 return 0;
79 }
80
81 static int config_input(AVFilterLink *link)
82 {
83 AVFilterContext *ctx = link->dst;
84 CropContext *crop = ctx->priv;
85
86 switch (link->format) {
87 case PIX_FMT_RGB48BE:
88 case PIX_FMT_RGB48LE:
89 crop->bpp = 48;
90 break;
91 case PIX_FMT_ARGB:
92 case PIX_FMT_RGBA:
93 case PIX_FMT_ABGR:
94 case PIX_FMT_BGRA:
95 crop->bpp = 32;
96 break;
97 case PIX_FMT_RGB24:
98 case PIX_FMT_BGR24:
99 crop->bpp = 24;
100 break;
101 case PIX_FMT_RGB565BE:
102 case PIX_FMT_RGB565LE:
103 case PIX_FMT_RGB555BE:
104 case PIX_FMT_RGB555LE:
105 case PIX_FMT_BGR565BE:
106 case PIX_FMT_BGR565LE:
107 case PIX_FMT_BGR555BE:
108 case PIX_FMT_BGR555LE:
109 case PIX_FMT_GRAY16BE:
110 case PIX_FMT_GRAY16LE:
111 case PIX_FMT_YUV420P16LE:
112 case PIX_FMT_YUV420P16BE:
113 case PIX_FMT_YUV422P16LE:
114 case PIX_FMT_YUV422P16BE:
115 case PIX_FMT_YUV444P16LE:
116 case PIX_FMT_YUV444P16BE:
117 crop->bpp = 16;
118 break;
119 default:
120 crop->bpp = 8;
121 }
122
123 avcodec_get_chroma_sub_sample(link->format, &crop->hsub, &crop->vsub);
124
125 if (crop->w == 0)
126 crop->w = link->w - crop->x;
127 if (crop->h == 0)
128 crop->h = link->h - crop->y;
129
130 crop->x &= ~((1 << crop->hsub) - 1);
131 crop->y &= ~((1 << crop->vsub) - 1);
132
133 av_log(link->dst, AV_LOG_INFO, "x:%d y:%d w:%d h:%d\n",
134 crop->x, crop->y, crop->w, crop->h);
135
136 if (crop->x < 0 || crop->y < 0 ||
137 crop->w <= 0 || crop->h <= 0 ||
138 (unsigned)crop->x + (unsigned)crop->w > link->w ||
139 (unsigned)crop->y + (unsigned)crop->h > link->h) {
140 av_log(ctx, AV_LOG_ERROR,
141 "Output area %d:%d:%d:%d not within the input area 0:0:%d:%d or zero-sized\n",
142 crop->x, crop->y, crop->w, crop->h, link->w, link->h);
143 return -1;
144 }
145
146 return 0;
147 }
148
149 static int config_output(AVFilterLink *link)
150 {
151 CropContext *crop = link->src->priv;
152
153 link->w = crop->w;
154 link->h = crop->h;
155
156 return 0;
157 }
158
159 static AVFilterPicRef *get_video_buffer(AVFilterLink *link, int perms,
160 int w, int h)
161 {
162 return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
163 }
164
165 static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
166 {
167 CropContext *crop = link->dst->priv;
168 AVFilterPicRef *ref2 = avfilter_ref_pic(picref, ~0);
169 int i;
170
171 ref2->w = crop->w;
172 ref2->h = crop->h;
173
174 ref2->data[0] += crop->y * ref2->linesize[0];
175 ref2->data[0] += (crop->x * crop->bpp) >> 3;
176
177 if (!(av_pix_fmt_descriptors[link->format].flags & PIX_FMT_PAL)) {
178 for (i = 1; i < 3; i ++) {
179 if (ref2->data[i]) {
180 ref2->data[i] += (crop->y >> crop->vsub) * ref2->linesize[i];
181 ref2->data[i] += ((crop->x * crop->bpp) >> 3) >> crop->hsub;
182 }
183 }
184 }
185
186 /* alpha plane */
187 if (ref2->data[3]) {
188 ref2->data[3] += crop->y * ref2->linesize[3];
189 ref2->data[3] += (crop->x * crop->bpp) >> 3;
190 }
191
192 avfilter_start_frame(link->dst->outputs[0], ref2);
193 }
194
195 static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
196 {
197 AVFilterContext *ctx = link->dst;
198 CropContext *crop = ctx->priv;
199
200 if (y >= crop->y + crop->h || y + h <= crop->y)
201 return;
202
203 if (y < crop->y) {
204 h -= crop->y - y;
205 y = crop->y;
206 }
207 if (y + h > crop->y + crop->h)
208 h = crop->y + crop->h - y;
209
210 avfilter_draw_slice(ctx->outputs[0], y - crop->y, h, slice_dir);
211 }
212
213 AVFilter avfilter_vf_crop = {
214 .name = "crop",
215 .description = NULL_IF_CONFIG_SMALL("Crop the input video to x:y:width:height."),
216
217 .priv_size = sizeof(CropContext),
218
219 .query_formats = query_formats,
220 .init = init,
221
222 .inputs = (AVFilterPad[]) {{ .name = "default",
223 .type = CODEC_TYPE_VIDEO,
224 .start_frame = start_frame,
225 .draw_slice = draw_slice,
226 .get_video_buffer = get_video_buffer,
227 .config_props = config_input, },
228 { .name = NULL}},
229 .outputs = (AVFilterPad[]) {{ .name = "default",
230 .type = CODEC_TYPE_VIDEO,
231 .config_props = config_output, },
232 { .name = NULL}},
233 };