FFmpeg
vf_lumakey.c
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1 /*
2  * Copyright (c) 2017 Paul B Mahol
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 LumakeyContext {
29  const AVClass *class;
30 
31  double threshold;
32  double tolerance;
33  double softness;
34 
35  int white;
36  int black;
37  int so;
38  int max;
39 
40  int (*do_lumakey_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
42 
43 static int do_lumakey_slice8(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
44 {
45  LumakeyContext *s = ctx->priv;
46  AVFrame *frame = arg;
47  const int slice_start = (frame->height * jobnr) / nb_jobs;
48  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
49  uint8_t *alpha = frame->data[3] + slice_start * frame->linesize[3];
50  const uint8_t *luma = frame->data[0] + slice_start * frame->linesize[0];
51  const int so = s->so;
52  const int w = s->white;
53  const int b = s->black;
54  int x, y;
55 
56  for (y = slice_start; y < slice_end; y++) {
57  for (x = 0; x < frame->width; x++) {
58  if (luma[x] >= b && luma[x] <= w) {
59  alpha[x] = 0;
60  } else if (luma[x] > b - so && luma[x] < w + so) {
61  if (luma[x] < b) {
62  alpha[x] = 255 - (luma[x] - b + so) * 255 / so;
63  } else {
64  alpha[x] = (luma[x] - w) * 255 / so;
65  }
66  }
67  }
68  luma += frame->linesize[0];
69  alpha += frame->linesize[3];
70  }
71 
72  return 0;
73 }
74 
75 static int do_lumakey_slice16(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
76 {
77  LumakeyContext *s = ctx->priv;
78  AVFrame *frame = arg;
79  const int slice_start = (frame->height * jobnr) / nb_jobs;
80  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
81  uint16_t *alpha = (uint16_t *)(frame->data[3] + slice_start * frame->linesize[3]);
82  const uint16_t *luma = (const uint16_t *)(frame->data[0] + slice_start * frame->linesize[0]);
83  const int so = s->so;
84  const int w = s->white;
85  const int b = s->black;
86  const int m = s->max;
87  int x, y;
88 
89  for (y = slice_start; y < slice_end; y++) {
90  for (x = 0; x < frame->width; x++) {
91  if (luma[x] >= b && luma[x] <= w) {
92  alpha[x] = 0;
93  } else if (luma[x] > b - so && luma[x] < w + so) {
94  if (luma[x] < b) {
95  alpha[x] = m - (luma[x] - b + so) * m / so;
96  } else {
97  alpha[x] = (luma[x] - w) * m / so;
98  }
99  }
100  }
101  luma += frame->linesize[0] / 2;
102  alpha += frame->linesize[3] / 2;
103  }
104 
105  return 0;
106 }
107 
109 {
111  AVFilterContext *ctx = inlink->dst;
112  LumakeyContext *s = ctx->priv;
113  int depth;
114 
115  depth = desc->comp[0].depth;
116  if (depth == 8) {
117  s->white = av_clip_uint8((s->threshold + s->tolerance) * 255);
118  s->black = av_clip_uint8((s->threshold - s->tolerance) * 255);
119  s->do_lumakey_slice = do_lumakey_slice8;
120  s->so = s->softness * 255;
121  } else {
122  s->max = (1 << depth) - 1;
123  s->white = av_clip((s->threshold + s->tolerance) * s->max, 0, s->max);
124  s->black = av_clip((s->threshold - s->tolerance) * s->max, 0, s->max);
125  s->do_lumakey_slice = do_lumakey_slice16;
126  s->so = s->softness * s->max;
127  }
128 
129  return 0;
130 }
131 
133 {
134  AVFilterContext *ctx = link->dst;
135  LumakeyContext *s = ctx->priv;
136  int ret;
137 
138  if (ret = ff_filter_execute(ctx, s->do_lumakey_slice, frame, NULL,
140  return ret;
141 
142  return ff_filter_frame(ctx->outputs[0], frame);
143 }
144 
146 {
147  static const enum AVPixelFormat pixel_fmts[] = {
154  };
155 
156  return ff_set_common_formats_from_list(ctx, pixel_fmts);
157 }
158 
159 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
160  char *res, int res_len, int flags)
161 {
162  int ret;
163 
164  ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
165  if (ret < 0)
166  return ret;
167 
168  return config_input(ctx->inputs[0]);
169 }
170 
171 static const AVFilterPad lumakey_inputs[] = {
172  {
173  .name = "default",
174  .type = AVMEDIA_TYPE_VIDEO,
176  .filter_frame = filter_frame,
177  .config_props = config_input,
178  },
179 };
180 
181 static const AVFilterPad lumakey_outputs[] = {
182  {
183  .name = "default",
184  .type = AVMEDIA_TYPE_VIDEO,
185  },
186 };
187 
188 #define OFFSET(x) offsetof(LumakeyContext, x)
189 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
190 
191 static const AVOption lumakey_options[] = {
192  { "threshold", "set the threshold value", OFFSET(threshold), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 1, FLAGS },
193  { "tolerance", "set the tolerance value", OFFSET(tolerance), AV_OPT_TYPE_DOUBLE, {.dbl=0.01}, 0, 1, FLAGS },
194  { "softness", "set the softness value", OFFSET(softness), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 1, FLAGS },
195  { NULL }
196 };
197 
198 AVFILTER_DEFINE_CLASS(lumakey);
199 
201  .name = "lumakey",
202  .description = NULL_IF_CONFIG_SMALL("Turns a certain luma into transparency."),
203  .priv_size = sizeof(LumakeyContext),
204  .priv_class = &lumakey_class,
209  .process_command = process_command,
210 };
LumakeyContext::max
int max
Definition: vf_lumakey.c:38
AV_PIX_FMT_YUVA422P16
#define AV_PIX_FMT_YUVA422P16
Definition: pixfmt.h:432
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
av_clip
#define av_clip
Definition: common.h:96
opt.h
do_lumakey_slice8
static int do_lumakey_slice8(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:43
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1019
av_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2540
LumakeyContext::so
int so
Definition: vf_lumakey.c:37
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
AV_PIX_FMT_YUVA422P9
#define AV_PIX_FMT_YUVA422P9
Definition: pixfmt.h:424
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AV_PIX_FMT_YUVA420P16
#define AV_PIX_FMT_YUVA420P16
Definition: pixfmt.h:431
w
uint8_t w
Definition: llviddspenc.c:38
LumakeyContext::softness
double softness
Definition: vf_lumakey.c:33
AV_PIX_FMT_YUVA420P10
#define AV_PIX_FMT_YUVA420P10
Definition: pixfmt.h:426
AVOption
AVOption.
Definition: opt.h:247
b
#define b
Definition: input.c:40
filter_frame
static int filter_frame(AVFilterLink *link, AVFrame *frame)
Definition: vf_lumakey.c:132
LumakeyContext
Definition: vf_lumakey.c:28
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
video.h
AV_PIX_FMT_YUVA422P10
#define AV_PIX_FMT_YUVA422P10
Definition: pixfmt.h:427
formats.h
AV_PIX_FMT_YUVA420P9
#define AV_PIX_FMT_YUVA420P9
Definition: pixfmt.h:423
AV_PIX_FMT_YUVA444P16
#define AV_PIX_FMT_YUVA444P16
Definition: pixfmt.h:433
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
av_cold
#define av_cold
Definition: attributes.h:90
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_PIX_FMT_YUVA420P
@ AV_PIX_FMT_YUVA420P
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
slice_end
static int slice_end(AVCodecContext *avctx, AVFrame *pict)
Handle slice ends.
Definition: mpeg12dec.c:2041
lumakey_inputs
static const AVFilterPad lumakey_inputs[]
Definition: vf_lumakey.c:171
ff_set_common_formats_from_list
int ff_set_common_formats_from_list(AVFilterContext *ctx, const int *fmts)
Equivalent to ff_set_common_formats(ctx, ff_make_format_list(fmts))
Definition: formats.c:703
AV_PIX_FMT_YUVA444P12
#define AV_PIX_FMT_YUVA444P12
Definition: pixfmt.h:430
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:152
LumakeyContext::black
int black
Definition: vf_lumakey.c:36
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
arg
const char * arg
Definition: jacosubdec.c:67
LumakeyContext::white
int white
Definition: vf_lumakey.c:35
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
LumakeyContext::threshold
double threshold
Definition: vf_lumakey.c:31
LumakeyContext::do_lumakey_slice
int(* do_lumakey_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:40
OFFSET
#define OFFSET(x)
Definition: vf_lumakey.c:188
lumakey_outputs
static const AVFilterPad lumakey_outputs[]
Definition: vf_lumakey.c:181
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:117
do_lumakey_slice16
static int do_lumakey_slice16(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:75
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:883
AV_PIX_FMT_YUVA444P
@ AV_PIX_FMT_YUVA444P
planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
Definition: pixfmt.h:167
AV_PIX_FMT_YUVA444P10
#define AV_PIX_FMT_YUVA444P10
Definition: pixfmt.h:428
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:130
LumakeyContext::tolerance
double tolerance
Definition: vf_lumakey.c:32
ff_filter_get_nb_threads
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:804
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
ff_vf_lumakey
const AVFilter ff_vf_lumakey
Definition: vf_lumakey.c:200
AVFilter
Filter definition.
Definition: avfilter.h:149
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_PIX_FMT_YUVA444P9
#define AV_PIX_FMT_YUVA444P9
Definition: pixfmt.h:425
config_input
static int config_input(AVFilterLink *inlink)
Definition: vf_lumakey.c:108
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AV_PIX_FMT_YUVA422P12
#define AV_PIX_FMT_YUVA422P12
Definition: pixfmt.h:429
avfilter.h
query_formats
static av_cold int query_formats(AVFilterContext *ctx)
Definition: vf_lumakey.c:145
lumakey_options
static const AVOption lumakey_options[]
Definition: vf_lumakey.c:191
av_clip_uint8
#define av_clip_uint8
Definition: common.h:102
AVFilterContext
An instance of a filter.
Definition: avfilter.h:346
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:121
desc
const char * desc
Definition: libsvtav1.c:79
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
alpha
static const int16_t alpha[]
Definition: ilbcdata.h:55
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:153
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: vf_lumakey.c:159
FLAGS
#define FLAGS
Definition: vf_lumakey.c:189
imgutils.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
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:143
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(lumakey)
int
int
Definition: ffmpeg_filter.c:156
AV_PIX_FMT_YUVA422P
@ AV_PIX_FMT_YUVA422P
planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
Definition: pixfmt.h:166
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:69