1 /*
2 * Copyright (c) 2015 Timo Rothenpieler <timo@rothenpieler.org>
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 #include "libavutil/opt.h"
22 #include "libavutil/imgutils.h"
23 #include "avfilter.h"
24 #include "formats.h"
25 #include "internal.h"
26 #include "video.h"
27
28 typedef struct ColorkeyContext {
29 const AVClass *class;
30
31 /* color offsets rgba */
32 int co[4];
33
34 uint8_t colorkey_rgba[4];
35 float similarity;
36 float blend;
37
38 int (*do_slice)(AVFilterContext *ctx, void *arg,
39 int jobnr, int nb_jobs);
40 } ColorkeyContext;
41
do_colorkey_pixel(ColorkeyContext * ctx,uint8_t r,uint8_t g,uint8_t b)42 static uint8_t do_colorkey_pixel(ColorkeyContext *ctx, uint8_t r, uint8_t g, uint8_t b)
43 {
44 int dr = (int)r - ctx->colorkey_rgba[0];
45 int dg = (int)g - ctx->colorkey_rgba[1];
46 int db = (int)b - ctx->colorkey_rgba[2];
47
48 double diff = sqrt((dr * dr + dg * dg + db * db) / (255.0 * 255.0 * 3.0));
49
50 if (ctx->blend > 0.0001) {
51 return av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0) * 255.0;
52 } else {
53 return (diff > ctx->similarity) ? 255 : 0;
54 }
55 }
56
do_colorkey_slice(AVFilterContext * avctx,void * arg,int jobnr,int nb_jobs)57 static int do_colorkey_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
58 {
59 AVFrame *frame = arg;
60
61 const int slice_start = (frame->height * jobnr) / nb_jobs;
62 const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
63
64 ColorkeyContext *ctx = avctx->priv;
65
66 int o, x, y;
67
68 for (y = slice_start; y < slice_end; ++y) {
69 for (x = 0; x < frame->width; ++x) {
70 o = frame->linesize[0] * y + x * 4;
71
72 frame->data[0][o + ctx->co[3]] =
73 do_colorkey_pixel(ctx,
74 frame->data[0][o + ctx->co[0]],
75 frame->data[0][o + ctx->co[1]],
76 frame->data[0][o + ctx->co[2]]);
77 }
78 }
79
80 return 0;
81 }
82
do_colorhold_slice(AVFilterContext * avctx,void * arg,int jobnr,int nb_jobs)83 static int do_colorhold_slice(AVFilterContext *avctx, void *arg, int jobnr, int nb_jobs)
84 {
85 AVFrame *frame = arg;
86
87 const int slice_start = (frame->height * jobnr) / nb_jobs;
88 const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
89
90 ColorkeyContext *ctx = avctx->priv;
91
92 int x, y;
93
94 for (y = slice_start; y < slice_end; ++y) {
95 for (x = 0; x < frame->width; ++x) {
96 int o, t, r, g, b;
97
98 o = frame->linesize[0] * y + x * 4;
99 r = frame->data[0][o + ctx->co[0]];
100 g = frame->data[0][o + ctx->co[1]];
101 b = frame->data[0][o + ctx->co[2]];
102
103 t = do_colorkey_pixel(ctx, r, g, b);
104
105 if (t > 0) {
106 int a = (r + g + b) / 3;
107 int rt = 255 - t;
108
109 frame->data[0][o + ctx->co[0]] = (a * t + r * rt + 127) >> 8;
110 frame->data[0][o + ctx->co[1]] = (a * t + g * rt + 127) >> 8;
111 frame->data[0][o + ctx->co[2]] = (a * t + b * rt + 127) >> 8;
112 }
113 }
114 }
115
116 return 0;
117 }
118
init_filter(AVFilterContext * avctx)119 static av_cold int init_filter(AVFilterContext *avctx)
120 {
121 ColorkeyContext *ctx = avctx->priv;
122
123 if (!strcmp(avctx->filter->name, "colorkey")) {
124 ctx->do_slice = do_colorkey_slice;
125 } else {
126 ctx->do_slice = do_colorhold_slice;
127 }
128
129 return 0;
130 }
131
filter_frame(AVFilterLink * link,AVFrame * frame)132 static int filter_frame(AVFilterLink *link, AVFrame *frame)
133 {
134 AVFilterContext *avctx = link->dst;
135 ColorkeyContext *ctx = avctx->priv;
136 int res;
137
138 if (res = av_frame_make_writable(frame))
139 return res;
140
141 if (res = avctx->internal->execute(avctx, ctx->do_slice, frame, NULL, FFMIN(frame->height, ff_filter_get_nb_threads(avctx))))
142 return res;
143
144 return ff_filter_frame(avctx->outputs[0], frame);
145 }
146
config_output(AVFilterLink * outlink)147 static av_cold int config_output(AVFilterLink *outlink)
148 {
149 AVFilterContext *avctx = outlink->src;
150 ColorkeyContext *ctx = avctx->priv;
151 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
152 int i;
153
154 outlink->w = avctx->inputs[0]->w;
155 outlink->h = avctx->inputs[0]->h;
156 outlink->time_base = avctx->inputs[0]->time_base;
157
158 for (i = 0; i < 4; ++i)
159 ctx->co[i] = desc->comp[i].offset;
160
161 return 0;
162 }
163
query_formats(AVFilterContext * avctx)164 static av_cold int query_formats(AVFilterContext *avctx)
165 {
166 static const enum AVPixelFormat pixel_fmts[] = {
167 AV_PIX_FMT_ARGB,
168 AV_PIX_FMT_RGBA,
169 AV_PIX_FMT_ABGR,
170 AV_PIX_FMT_BGRA,
171 AV_PIX_FMT_NONE
172 };
173
174 AVFilterFormats *formats = NULL;
175
176 formats = ff_make_format_list(pixel_fmts);
177 if (!formats)
178 return AVERROR(ENOMEM);
179
180 return ff_set_common_formats(avctx, formats);
181 }
182
183 static const AVFilterPad colorkey_inputs[] = {
184 {
185 .name = "default",
186 .type = AVMEDIA_TYPE_VIDEO,
187 .filter_frame = filter_frame,
188 },
189 { NULL }
190 };
191
192 static const AVFilterPad colorkey_outputs[] = {
193 {
194 .name = "default",
195 .type = AVMEDIA_TYPE_VIDEO,
196 .config_props = config_output,
197 },
198 { NULL }
199 };
200
201 #define OFFSET(x) offsetof(ColorkeyContext, x)
202 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
203
204 #if CONFIG_COLORKEY_FILTER
205
206 static const AVOption colorkey_options[] = {
207 { "color", "set the colorkey key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
208 { "similarity", "set the colorkey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
209 { "blend", "set the colorkey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
210 { NULL }
211 };
212
213 AVFILTER_DEFINE_CLASS(colorkey);
214
215 AVFilter ff_vf_colorkey = {
216 .name = "colorkey",
217 .description = NULL_IF_CONFIG_SMALL("Turns a certain color into transparency. Operates on RGB colors."),
218 .priv_size = sizeof(ColorkeyContext),
219 .priv_class = &colorkey_class,
220 .query_formats = query_formats,
221 .init = init_filter,
222 .inputs = colorkey_inputs,
223 .outputs = colorkey_outputs,
224 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
225 .process_command = ff_filter_process_command,
226 };
227
228 #endif /* CONFIG_COLORKEY_FILTER */
229 #if CONFIG_COLORHOLD_FILTER
230
231 static const AVOption colorhold_options[] = {
232 { "color", "set the colorhold key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
233 { "similarity", "set the colorhold similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
234 { "blend", "set the colorhold blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
235 { NULL }
236 };
237
238 AVFILTER_DEFINE_CLASS(colorhold);
239
240 AVFilter ff_vf_colorhold = {
241 .name = "colorhold",
242 .description = NULL_IF_CONFIG_SMALL("Turns a certain color range into gray. Operates on RGB colors."),
243 .priv_size = sizeof(ColorkeyContext),
244 .priv_class = &colorhold_class,
245 .query_formats = query_formats,
246 .init = init_filter,
247 .inputs = colorkey_inputs,
248 .outputs = colorkey_outputs,
249 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,
250 .process_command = ff_filter_process_command,
251 };
252
253 #endif /* CONFIG_COLORHOLD_FILTER */
254