FFmpeg
vf_colorkey.c
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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 "config_components.h"
22 
23 #include "libavutil/opt.h"
24 #include "libavutil/pixdesc.h"
25 #include "avfilter.h"
26 #include "drawutils.h"
27 #include "internal.h"
28 
29 typedef struct ColorkeyContext {
30  const AVClass *class;
31 
32  /* color offsets rgba */
33  uint8_t co[4];
34 
35  uint8_t colorkey_rgba[4];
36  float similarity;
37  float blend;
38  double scale;
39  int depth;
40  int max;
41 
43  int jobnr, int nb_jobs);
45 
46 static int do_colorkey_pixel(const uint8_t *colorkey_rgba, int r, int g, int b,
47  float similarity, float iblend, int max, double scale)
48 {
49  double dr, dg, db, diff;
50 
51  dr = r * scale - colorkey_rgba[0];
52  dg = g * scale - colorkey_rgba[1];
53  db = b * scale - colorkey_rgba[2];
54 
55  diff = sqrt((dr * dr + dg * dg + db * db) / (255.0 * 255.0 * 3.0));
56 
57  if (iblend < 10000.0) {
58  return av_clipd((diff - similarity) * iblend, 0.0, 1.0) * max;
59  } else {
60  return (diff > similarity) ? max : 0;
61  }
62 }
63 
64 #define COLORKEY_SLICE(name, type) \
65 static int do_colorkey_slice##name(AVFilterContext *avctx, \
66  void *arg, \
67  int jobnr, int nb_jobs) \
68 { \
69  AVFrame *frame = arg; \
70  const int slice_start = (frame->height * jobnr) / nb_jobs; \
71  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs; \
72  ColorkeyContext *ctx = avctx->priv; \
73  const float similarity = ctx->similarity; \
74  const float iblend = 1.f / ctx->blend; \
75  const uint8_t *colorkey_rgba = ctx->colorkey_rgba; \
76  const uint8_t *co = ctx->co; \
77  const double scale = ctx->scale; \
78  const int max = ctx->max; \
79  \
80  for (int y = slice_start; y < slice_end; y++) { \
81  type *dst = (type *)(frame->data[0] + y * frame->linesize[0]);\
82  \
83  for (int x = 0; x < frame->width; x++) { \
84  const int o = x * 4; \
85  \
86  dst[o + co[3]] = do_colorkey_pixel(colorkey_rgba, \
87  dst[o + co[0]], \
88  dst[o + co[1]], \
89  dst[o + co[2]], \
90  similarity, iblend, max, scale); \
91  } \
92  } \
93  \
94  return 0; \
95 }
96 
97 COLORKEY_SLICE(8, uint8_t)
98 COLORKEY_SLICE(16, uint16_t)
99 
100 #define COLORHOLD_SLICE(name, type, htype) \
101 static int do_colorhold_slice##name(AVFilterContext *avctx, void *arg, \
102  int jobnr, int nb_jobs) \
103 { \
104  AVFrame *frame = arg; \
105  const int slice_start = (frame->height * jobnr) / nb_jobs; \
106  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs; \
107  ColorkeyContext *ctx = avctx->priv; \
108  const int depth = ctx->depth; \
109  const int max = ctx->max; \
110  const int half = max / 2; \
111  const uint8_t *co = ctx->co; \
112  const uint8_t *colorkey_rgba = ctx->colorkey_rgba; \
113  const float similarity = ctx->similarity; \
114  const float iblend = 1.f / ctx->blend; \
115  const double scale = ctx->scale; \
116  \
117  for (int y = slice_start; y < slice_end; ++y) { \
118  type *dst = (type *)(frame->data[0] + y * frame->linesize[0]); \
119  \
120  for (int x = 0; x < frame->width; ++x) { \
121  int o, t, r, g, b; \
122  \
123  o = x * 4; \
124  r = dst[o + co[0]]; \
125  g = dst[o + co[1]]; \
126  b = dst[o + co[2]]; \
127  \
128  t = do_colorkey_pixel(colorkey_rgba, r, g, b, \
129  similarity, iblend, max, scale); \
130  \
131  if (t > 0) { \
132  htype a = (r + g + b) / 3; \
133  htype rt = max - t; \
134  \
135  dst[o + co[0]] = (a * t + r * rt + half) >> depth; \
136  dst[o + co[1]] = (a * t + g * rt + half) >> depth; \
137  dst[o + co[2]] = (a * t + b * rt + half) >> depth; \
138  } \
139  } \
140  } \
141  \
142  return 0; \
143 }
144 
145 COLORHOLD_SLICE(8, uint8_t, int)
146 COLORHOLD_SLICE(16, uint16_t, int64_t)
147 
149 {
150  AVFilterContext *avctx = link->dst;
151  ColorkeyContext *ctx = avctx->priv;
152  int res;
153 
154  if (res = ff_filter_execute(avctx, ctx->do_slice, frame, NULL,
156  return res;
157 
158  return ff_filter_frame(avctx->outputs[0], frame);
159 }
160 
161 static av_cold int config_output(AVFilterLink *outlink)
162 {
163  AVFilterContext *avctx = outlink->src;
164  ColorkeyContext *ctx = avctx->priv;
166 
167  ctx->depth = desc->comp[0].depth;
168  ctx->max = (1 << ctx->depth) - 1;
169  ctx->scale = 255.0 / ctx->max;
170  outlink->w = avctx->inputs[0]->w;
171  outlink->h = avctx->inputs[0]->h;
172  outlink->time_base = avctx->inputs[0]->time_base;
173  ff_fill_rgba_map(ctx->co, outlink->format);
174 
175  if (!strcmp(avctx->filter->name, "colorkey")) {
176  ctx->do_slice = ctx->max == 255 ? do_colorkey_slice8 : do_colorkey_slice16;
177  } else {
178  ctx->do_slice = ctx->max == 255 ? do_colorhold_slice8 : do_colorhold_slice16;
179  }
180 
181  return 0;
182 }
183 
184 static const enum AVPixelFormat pixel_fmts[] = {
192 };
193 
194 static const AVFilterPad colorkey_inputs[] = {
195  {
196  .name = "default",
197  .type = AVMEDIA_TYPE_VIDEO,
199  .filter_frame = filter_frame,
200  },
201 };
202 
203 static const AVFilterPad colorkey_outputs[] = {
204  {
205  .name = "default",
206  .type = AVMEDIA_TYPE_VIDEO,
207  .config_props = config_output,
208  },
209 };
210 
211 #define OFFSET(x) offsetof(ColorkeyContext, x)
212 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
213 
214 #if CONFIG_COLORKEY_FILTER
215 
216 static const AVOption colorkey_options[] = {
217  { "color", "set the colorkey key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
218  { "similarity", "set the colorkey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.00001, 1.0, FLAGS },
219  { "blend", "set the colorkey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
220  { NULL }
221 };
222 
223 AVFILTER_DEFINE_CLASS(colorkey);
224 
225 const AVFilter ff_vf_colorkey = {
226  .name = "colorkey",
227  .description = NULL_IF_CONFIG_SMALL("Turns a certain color into transparency. Operates on RGB colors."),
228  .priv_size = sizeof(ColorkeyContext),
229  .priv_class = &colorkey_class,
234  .process_command = ff_filter_process_command,
235 };
236 
237 #endif /* CONFIG_COLORKEY_FILTER */
238 #if CONFIG_COLORHOLD_FILTER
239 
240 static const AVOption colorhold_options[] = {
241  { "color", "set the colorhold key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, 0, 0, FLAGS },
242  { "similarity", "set the colorhold similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.00001, 1.0, FLAGS },
243  { "blend", "set the colorhold blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
244  { NULL }
245 };
246 
247 AVFILTER_DEFINE_CLASS(colorhold);
248 
249 const AVFilter ff_vf_colorhold = {
250  .name = "colorhold",
251  .description = NULL_IF_CONFIG_SMALL("Turns a certain color range into gray. Operates on RGB colors."),
252  .priv_size = sizeof(ColorkeyContext),
253  .priv_class = &colorhold_class,
258  .process_command = ff_filter_process_command,
259 };
260 
261 #endif /* CONFIG_COLORHOLD_FILTER */
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
r
const char * r
Definition: vf_curves.c:126
opt.h
colorkey_outputs
static const AVFilterPad colorkey_outputs[]
Definition: vf_colorkey.c:203
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1007
av_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2968
ff_vf_colorhold
const AVFilter ff_vf_colorhold
FILTER_PIXFMTS_ARRAY
#define FILTER_PIXFMTS_ARRAY(array)
Definition: internal.h:162
ColorkeyContext::scale
double scale
Definition: vf_colorkey.c:38
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
ColorkeyContext::max
int max
Definition: vf_colorkey.c:40
pixdesc.h
AVOption
AVOption.
Definition: opt.h:251
b
#define b
Definition: input.c:41
AV_PIX_FMT_BGRA
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:102
max
#define max(a, b)
Definition: cuda_runtime.h:33
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
ColorkeyContext::co
uint8_t co[4]
Definition: vf_colorkey.c:33
COLORKEY_SLICE
#define COLORKEY_SLICE(name, type)
Definition: vf_colorkey.c:64
COLORHOLD_SLICE
#define COLORHOLD_SLICE(name, type, htype)
Definition: vf_colorkey.c:100
AVFilterContext::priv
void * priv
private data for use by the filter
Definition: avfilter.h:424
ColorkeyContext::blend
float blend
Definition: vf_colorkey.c:37
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
ColorkeyContext::do_slice
int(* do_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_colorkey.c:42
av_cold
#define av_cold
Definition: attributes.h:90
filter_frame
static int filter_frame(AVFilterLink *link, AVFrame *frame)
Definition: vf_colorkey.c:148
g
const char * g
Definition: vf_curves.c:127
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ColorkeyContext::colorkey_rgba
uint8_t colorkey_rgba[4]
Definition: vf_colorkey.c:35
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
link
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a link
Definition: filter_design.txt:23
AV_PIX_FMT_RGBA
@ AV_PIX_FMT_RGBA
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:100
frame
static AVFrame * frame
Definition: demux_decode.c:54
arg
const char * arg
Definition: jacosubdec.c:67
AV_PIX_FMT_RGBA64
#define AV_PIX_FMT_RGBA64
Definition: pixfmt.h:472
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
ColorkeyContext
Definition: vf_colorkey.c:29
AV_OPT_TYPE_COLOR
@ AV_OPT_TYPE_COLOR
Definition: opt.h:240
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:417
AV_PIX_FMT_ABGR
@ AV_PIX_FMT_ABGR
packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
Definition: pixfmt.h:101
scale
static void scale(int *out, const int *in, const int w, const int h, const int shift)
Definition: vvc_intra.c:292
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:106
ff_filter_process_command
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
Definition: avfilter.c:879
diff
static av_always_inline int diff(const struct color_info *a, const struct color_info *b, const int trans_thresh)
Definition: vf_paletteuse.c:164
ColorkeyContext::similarity
float similarity
Definition: vf_colorkey.c:36
colorkey_inputs
static const AVFilterPad colorkey_inputs[]
Definition: vf_colorkey.c:194
internal.h
AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:147
AVFILTER_DEFINE_CLASS
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:315
AV_PIX_FMT_ARGB
@ AV_PIX_FMT_ARGB
packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
Definition: pixfmt.h:99
AV_OPT_TYPE_FLOAT
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:228
AV_PIX_FMT_BGRA64
#define AV_PIX_FMT_BGRA64
Definition: pixfmt.h:477
FLAGS
#define FLAGS
Definition: vf_colorkey.c:212
ff_filter_get_nb_threads
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:814
ColorkeyContext::depth
int depth
Definition: vf_colorkey.c:39
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
AVFilter
Filter definition.
Definition: avfilter.h:166
pixel_fmts
static enum AVPixelFormat pixel_fmts[]
Definition: vf_colorkey.c:184
AVFrame::height
int height
Definition: frame.h:412
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
avfilter.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:409
AVFILTER_FLAG_SLICE_THREADS
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
Definition: avfilter.h:117
desc
const char * desc
Definition: libsvtav1.c:83
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPixFmtDescriptor
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:69
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
ff_fill_rgba_map
int ff_fill_rgba_map(uint8_t *rgba_map, enum AVPixelFormat pix_fmt)
Definition: drawutils.c:35
OFFSET
#define OFFSET(x)
Definition: vf_colorkey.c:211
AVFilterContext::filter
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:412
drawutils.h
ff_filter_execute
static av_always_inline int ff_filter_execute(AVFilterContext *ctx, avfilter_action_func *func, void *arg, int *ret, int nb_jobs)
Definition: internal.h:134
do_colorkey_pixel
static int do_colorkey_pixel(const uint8_t *colorkey_rgba, int r, int g, int b, float similarity, float iblend, int max, double scale)
Definition: vf_colorkey.c:46
int
int
Definition: ffmpeg_filter.c:424
av_clipd
av_clipd
Definition: af_crystalizer.c:131
config_output
static av_cold int config_output(AVFilterLink *outlink)
Definition: vf_colorkey.c:161
ff_vf_colorkey
const AVFilter ff_vf_colorkey
AVFilterContext::outputs
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:421
AVFILTERPAD_FLAG_NEEDS_WRITABLE
#define AVFILTERPAD_FLAG_NEEDS_WRITABLE
The filter expects writable frames from its input link, duplicating data buffers if needed.
Definition: internal.h:52