FFmpeg  4.0
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  int threshold;
32  int tolerance;
33  int softness;
34 
35  int white;
36  int black;
37  int max;
38 
39  int (*do_lumakey_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
41 
42 static int do_lumakey_slice8(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
43 {
44  LumakeyContext *s = ctx->priv;
45  AVFrame *frame = arg;
46  const int slice_start = (frame->height * jobnr) / nb_jobs;
47  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
48  uint8_t *alpha = frame->data[3] + slice_start * frame->linesize[3];
49  const uint8_t *luma = frame->data[0] + slice_start * frame->linesize[0];
50  const int so = s->softness;
51  const int w = s->white;
52  const int b = s->black;
53  int x, y;
54 
55  for (y = slice_start; y < slice_end; y++) {
56  for (x = 0; x < frame->width; x++) {
57  if (luma[x] >= b && luma[x] <= w) {
58  alpha[x] = 0;
59  } else if (luma[x] > b - so && luma[x] < w + so) {
60  if (luma[x] < b) {
61  alpha[x] = 255 - (luma[x] - b + so) * 255 / so;
62  } else {
63  alpha[x] = (luma[x] - w) * 255 / so;
64  }
65  }
66  }
67  luma += frame->linesize[0];
68  alpha += frame->linesize[3];
69  }
70 
71  return 0;
72 }
73 
74 static int do_lumakey_slice16(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
75 {
76  LumakeyContext *s = ctx->priv;
77  AVFrame *frame = arg;
78  const int slice_start = (frame->height * jobnr) / nb_jobs;
79  const int slice_end = (frame->height * (jobnr + 1)) / nb_jobs;
80  uint16_t *alpha = (uint16_t *)(frame->data[3] + slice_start * frame->linesize[3]);
81  const uint16_t *luma = (const uint16_t *)(frame->data[0] + slice_start * frame->linesize[0]);
82  const int so = s->softness;
83  const int w = s->white;
84  const int b = s->black;
85  const int m = s->max;
86  int x, y;
87 
88  for (y = slice_start; y < slice_end; y++) {
89  for (x = 0; x < frame->width; x++) {
90  if (luma[x] >= b && luma[x] <= w) {
91  alpha[x] = 0;
92  } else if (luma[x] > b - so && luma[x] < w + so) {
93  if (luma[x] < b) {
94  alpha[x] = m - (luma[x] - b + so) * m / so;
95  } else {
96  alpha[x] = (luma[x] - w) * m / so;
97  }
98  }
99  }
100  luma += frame->linesize[0] / 2;
101  alpha += frame->linesize[3] / 2;
102  }
103 
104  return 0;
105 }
106 
107 static int config_input(AVFilterLink *inlink)
108 {
110  AVFilterContext *ctx = inlink->dst;
111  LumakeyContext *s = ctx->priv;
112  int depth;
113 
114  depth = desc->comp[0].depth;
115  if (depth == 8) {
116  s->white = av_clip_uint8(s->threshold + s->tolerance);
117  s->black = av_clip_uint8(s->threshold - s->tolerance);
119  } else {
120  s->max = (1 << depth) - 1;
121  s->white = av_clip(s->threshold + s->tolerance, 0, s->max);
122  s->black = av_clip(s->threshold - s->tolerance, 0, s->max);
124  }
125 
126  return 0;
127 }
128 
130 {
131  AVFilterContext *ctx = link->dst;
132  LumakeyContext *s = ctx->priv;
133  int ret;
134 
135  if (ret = av_frame_make_writable(frame))
136  return ret;
137 
138  if (ret = ctx->internal->execute(ctx, s->do_lumakey_slice, frame, NULL, FFMIN(frame->height, ff_filter_get_nb_threads(ctx))))
139  return ret;
140 
141  return ff_filter_frame(ctx->outputs[0], frame);
142 }
143 
145 {
146  static const enum AVPixelFormat pixel_fmts[] = {
152  };
154 
155  formats = ff_make_format_list(pixel_fmts);
156  if (!formats)
157  return AVERROR(ENOMEM);
158 
159  return ff_set_common_formats(ctx, formats);
160 }
161 
162 static const AVFilterPad lumakey_inputs[] = {
163  {
164  .name = "default",
165  .type = AVMEDIA_TYPE_VIDEO,
166  .filter_frame = filter_frame,
167  .config_props = config_input,
168  },
169  { NULL }
170 };
171 
172 static const AVFilterPad lumakey_outputs[] = {
173  {
174  .name = "default",
175  .type = AVMEDIA_TYPE_VIDEO,
176  },
177  { NULL }
178 };
179 
180 #define OFFSET(x) offsetof(LumakeyContext, x)
181 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
182 
183 static const AVOption lumakey_options[] = {
184  { "threshold", "set the threshold value", OFFSET(threshold), AV_OPT_TYPE_INT, {.i64=0}, 0, UINT16_MAX, FLAGS },
185  { "tolerance", "set the tolerance value", OFFSET(tolerance), AV_OPT_TYPE_INT, {.i64=1}, 0, UINT16_MAX, FLAGS },
186  { "softness", "set the softness value", OFFSET(softness), AV_OPT_TYPE_INT, {.i64=0}, 0, UINT16_MAX, FLAGS },
187  { NULL }
188 };
189 
190 AVFILTER_DEFINE_CLASS(lumakey);
191 
193  .name = "lumakey",
194  .description = NULL_IF_CONFIG_SMALL("Turns a certain luma into transparency."),
195  .priv_size = sizeof(LumakeyContext),
196  .priv_class = &lumakey_class,
198  .inputs = lumakey_inputs,
199  .outputs = lumakey_outputs,
201 };
#define NULL
Definition: coverity.c:32
static int do_lumakey_slice8(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:42
#define AV_PIX_FMT_YUVA422P16
Definition: pixfmt.h:407
const char * s
Definition: avisynth_c.h:768
#define AV_PIX_FMT_YUVA422P9
Definition: pixfmt.h:401
static float alpha(float a)
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2363
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
AVOption.
Definition: opt.h:246
#define AV_PIX_FMT_YUVA420P10
Definition: pixfmt.h:403
static const AVFilterPad lumakey_outputs[]
Definition: vf_lumakey.c:172
static int do_lumakey_slice16(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:74
#define AV_PIX_FMT_YUVA422P10
Definition: pixfmt.h:404
misc image utilities
Main libavfilter public API header.
const char * desc
Definition: nvenc.c:65
const char * b
Definition: vf_curves.c:113
int(* do_lumakey_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: vf_lumakey.c:39
static const AVOption lumakey_options[]
Definition: vf_lumakey.c:183
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
#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:125
const char * name
Pad name.
Definition: internal.h:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:97
AVComponentDescriptor comp[4]
Parameters that describe how pixels are packed.
Definition: pixdesc.h:117
uint8_t
#define av_cold
Definition: attributes.h:82
AVOptions.
#define AV_PIX_FMT_YUVA420P9
Definition: pixfmt.h:400
static AVFrame * frame
static int flags
Definition: log.c:55
#define AV_PIX_FMT_YUVA420P16
Definition: pixfmt.h:406
AVFILTER_DEFINE_CLASS(lumakey)
A filter pad used for either input or output.
Definition: internal.h:54
planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
Definition: pixfmt.h:172
int width
Definition: frame.h:276
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:568
#define FLAGS
Definition: vf_lumakey.c:181
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
Definition: avfilter.h:116
AVFilter ff_vf_lumakey
Definition: vf_lumakey.c:192
#define AV_PIX_FMT_YUVA444P16
Definition: pixfmt.h:408
const char * arg
Definition: jacosubdec.c:66
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:802
#define FFMIN(a, b)
Definition: common.h:96
uint8_t w
Definition: llviddspenc.c:38
AVFormatContext * ctx
Definition: movenc.c:48
#define AV_PIX_FMT_YUVA444P10
Definition: pixfmt.h:405
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
static const AVFilterPad lumakey_inputs[]
Definition: vf_lumakey.c:162
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
Definition: pixfmt.h:173
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
#define OFFSET(x)
Definition: vf_lumakey.c:180
static av_cold int query_formats(AVFilterContext *ctx)
Definition: vf_lumakey.c:144
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:609
AVFilterInternal * internal
An opaque struct for libavfilter internal use.
Definition: avfilter.h:378
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
int
#define AV_PIX_FMT_YUVA444P9
Definition: pixfmt.h:402
avfilter_execute_func * execute
Definition: internal.h:155
static int slice_end(AVCodecContext *avctx, AVFrame *pict)
Handle slice ends.
Definition: mpeg12dec.c:2029
static int filter_frame(AVFilterLink *link, AVFrame *frame)
Definition: vf_lumakey.c:129
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
int height
Definition: frame.h:276
static int config_input(AVFilterLink *inlink)
Definition: vf_lumakey.c:107
formats
Definition: signature.h:48
internal API functions
int depth
Number of bits in the component.
Definition: pixdesc.h:58
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60