Add video crop filter.
[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
28 typedef struct {
29 int x; ///< x offset of the non-cropped area with respect to the input area
30 int y; ///< y offset of the non-cropped area with respect to the input area
31 int w; ///< width of the cropped area
32 int h; ///< height of the cropped area
33
34 int bpp; ///< bits per pixel
35 int hsub, vsub; ///< chroma subsampling
36 } CropContext;
37
38 static int query_formats(AVFilterContext *ctx)
39 {
40 enum PixelFormat pix_fmts[] = {
41 PIX_FMT_RGB48BE, PIX_FMT_RGB48LE,
42 PIX_FMT_ARGB, PIX_FMT_RGBA,
43 PIX_FMT_ABGR, PIX_FMT_BGRA,
44 PIX_FMT_RGB24, PIX_FMT_BGR24,
45 PIX_FMT_RGB565BE, PIX_FMT_RGB565LE,
46 PIX_FMT_RGB555BE, PIX_FMT_RGB555LE,
47 PIX_FMT_BGR565BE, PIX_FMT_BGR565LE,
48 PIX_FMT_BGR555BE, PIX_FMT_BGR555LE,
49 PIX_FMT_GRAY16BE, PIX_FMT_GRAY16LE,
50 PIX_FMT_YUV420P16LE, PIX_FMT_YUV420P16BE,
51 PIX_FMT_YUV422P16LE, PIX_FMT_YUV422P16BE,
52 PIX_FMT_YUV444P16LE, PIX_FMT_YUV444P16BE,
53 PIX_FMT_YUV444P, PIX_FMT_YUV422P,
54 PIX_FMT_YUV420P, PIX_FMT_YUV411P,
55 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
56 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P,
57 PIX_FMT_YUVJ420P, PIX_FMT_YUVJ440P,
58 PIX_FMT_YUVA420P,
59 PIX_FMT_NV12, PIX_FMT_NV21,
60 PIX_FMT_YUYV422, PIX_FMT_UYVY422,
61 PIX_FMT_UYYVYY411,
62 PIX_FMT_RGB8, PIX_FMT_BGR8,
63 PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE,
64 PIX_FMT_PAL8, PIX_FMT_GRAY8,
65 PIX_FMT_NONE
66 };
67
68 avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
69
70 return 0;
71 }
72
73 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
74 {
75 CropContext *crop = ctx->priv;
76
77 if (args)
78 sscanf(args, "%d:%d:%d:%d", &crop->x, &crop->y, &crop->w, &crop->h);
79
80 return 0;
81 }
82
83 static int config_input(AVFilterLink *link)
84 {
85 AVFilterContext *ctx = link->dst;
86 CropContext *crop = ctx->priv;
87
88 switch (link->format) {
89 case PIX_FMT_RGB48BE:
90 case PIX_FMT_RGB48LE:
91 crop->bpp = 48;
92 break;
93 case PIX_FMT_ARGB:
94 case PIX_FMT_RGBA:
95 case PIX_FMT_ABGR:
96 case PIX_FMT_BGRA:
97 crop->bpp = 32;
98 break;
99 case PIX_FMT_RGB24:
100 case PIX_FMT_BGR24:
101 crop->bpp = 24;
102 break;
103 case PIX_FMT_RGB565BE:
104 case PIX_FMT_RGB565LE:
105 case PIX_FMT_RGB555BE:
106 case PIX_FMT_RGB555LE:
107 case PIX_FMT_BGR565BE:
108 case PIX_FMT_BGR565LE:
109 case PIX_FMT_BGR555BE:
110 case PIX_FMT_BGR555LE:
111 case PIX_FMT_GRAY16BE:
112 case PIX_FMT_GRAY16LE:
113 case PIX_FMT_YUV420P16LE:
114 case PIX_FMT_YUV420P16BE:
115 case PIX_FMT_YUV422P16LE:
116 case PIX_FMT_YUV422P16BE:
117 case PIX_FMT_YUV444P16LE:
118 case PIX_FMT_YUV444P16BE:
119 crop->bpp = 16;
120 break;
121 default:
122 crop->bpp = 8;
123 }
124
125 avcodec_get_chroma_sub_sample(link->format, &crop->hsub, &crop->vsub);
126
127 if (crop->w == 0)
128 crop->w = link->w - crop->x;
129 if (crop->h == 0)
130 crop->h = link->h - crop->y;
131
132 crop->x &= ~((1 << crop->hsub) - 1);
133 crop->y &= ~((1 << crop->vsub) - 1);
134
135 av_log(link->dst, AV_LOG_INFO, "x:%d y:%d w:%d h:%d\n",
136 crop->x, crop->y, crop->w, crop->h);
137
138 if (crop->x < 0 || crop->y < 0 ||
139 crop->w <= 0 || crop->h <= 0 ||
140 (unsigned)crop->x + (unsigned)crop->w > link->w ||
141 (unsigned)crop->y + (unsigned)crop->h > link->h) {
142 av_log(ctx, AV_LOG_ERROR,
143 "Output area %d:%d:%d:%d not within the input area 0:0:%d:%d or zero-sized\n",
144 crop->x, crop->y, crop->w, crop->h, link->w, link->h);
145 return -1;
146 }
147
148 return 0;
149 }
150
151 static int config_output(AVFilterLink *link)
152 {
153 CropContext *crop = link->src->priv;
154
155 link->w = crop->w;
156 link->h = crop->h;
157
158 return 0;
159 }
160
161 static AVFilterPicRef *get_video_buffer(AVFilterLink *link, int perms,
162 int w, int h)
163 {
164 return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
165 }
166
167 static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
168 {
169 CropContext *crop = link->dst->priv;
170 AVFilterPicRef *ref2 = avfilter_ref_pic(picref, ~0);
171 int i;
172
173 ref2->w = crop->w;
174 ref2->h = crop->h;
175
176 ref2->data[0] += crop->y * ref2->linesize[0];
177 ref2->data[0] += (crop->x * crop->bpp) >> 3;
178
179 if (link->format != PIX_FMT_PAL8) {
180 for (i = 1; i < 3; i ++) {
181 if (ref2->data[i]) {
182 ref2->data[i] += (crop->y >> crop->vsub) * ref2->linesize[i];
183 ref2->data[i] += crop->x >> crop->hsub;
184 }
185 }
186 }
187
188 /* alpha plane */
189 if (ref2->data[3]) {
190 ref2->data[3] += crop->y * ref2->linesize[3];
191 ref2->data[3] += (crop->x * crop->bpp) >> 3;
192 }
193
194 avfilter_start_frame(link->dst->outputs[0], ref2);
195 }
196
197 static void draw_slice(AVFilterLink *link, int y, int h)
198 {
199 AVFilterContext *ctx = link->dst;
200 CropContext *crop = ctx->priv;
201
202 if (y >= crop->y + crop->h || y + h <= crop->y)
203 return;
204
205 if (y < crop->y) {
206 h -= crop->y - y;
207 y = crop->y;
208 }
209 if (y + h > crop->y + crop->h)
210 h = crop->y + crop->h - y;
211
212 avfilter_draw_slice(ctx->outputs[0], y - crop->y, h);
213 }
214
215 AVFilter avfilter_vf_crop = {
216 .name = "crop",
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 };