2 * Copyright (c) 2017 Paul B Mahol
4 * This file is part of FFmpeg.
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.
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.
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
21 #include "libavutil/opt.h"
22 #include "libavutil/imgutils.h"
28 typedef struct LumakeyContext {
39 int (*do_lumakey_slice)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);
42 static int do_lumakey_slice8(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
44 LumakeyContext *s = ctx->priv;
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;
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) {
59 } else if (luma[x] > b - so && luma[x] < w + so) {
61 alpha[x] = 255 - (luma[x] - b + so) * 255 / so;
63 alpha[x] = (luma[x] - w) * 255 / so;
67 luma += frame->linesize[0];
68 alpha += frame->linesize[3];
74 static int do_lumakey_slice16(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
76 LumakeyContext *s = ctx->priv;
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;
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) {
92 } else if (luma[x] > b - so && luma[x] < w + so) {
94 alpha[x] = m - (luma[x] - b + so) * m / so;
96 alpha[x] = (luma[x] - w) * m / so;
100 luma += frame->linesize[0] / 2;
101 alpha += frame->linesize[3] / 2;
107 static int config_input(AVFilterLink *inlink)
109 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
110 AVFilterContext *ctx = inlink->dst;
111 LumakeyContext *s = ctx->priv;
114 depth = desc->comp[0].depth;
116 s->white = av_clip_uint8(s->threshold + s->tolerance);
117 s->black = av_clip_uint8(s->threshold - s->tolerance);
118 s->do_lumakey_slice = do_lumakey_slice8;
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);
123 s->do_lumakey_slice = do_lumakey_slice16;
129 static int filter_frame(AVFilterLink *link, AVFrame *frame)
131 AVFilterContext *ctx = link->dst;
132 LumakeyContext *s = ctx->priv;
135 if (ret = av_frame_make_writable(frame))
138 if (ret = ctx->internal->execute(ctx, s->do_lumakey_slice, frame, NULL, FFMIN(frame->height, ff_filter_get_nb_threads(ctx))))
141 return ff_filter_frame(ctx->outputs[0], frame);
144 static av_cold int query_formats(AVFilterContext *ctx)
146 static const enum AVPixelFormat pixel_fmts[] = {
147 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
148 AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA420P9,
149 AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA420P10,
150 AV_PIX_FMT_YUVA444P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA420P16,
153 AVFilterFormats *formats;
155 formats = ff_make_format_list(pixel_fmts);
157 return AVERROR(ENOMEM);
159 return ff_set_common_formats(ctx, formats);
162 static const AVFilterPad lumakey_inputs[] = {
165 .type = AVMEDIA_TYPE_VIDEO,
166 .filter_frame = filter_frame,
167 .config_props = config_input,
172 static const AVFilterPad lumakey_outputs[] = {
175 .type = AVMEDIA_TYPE_VIDEO,
180 #define OFFSET(x) offsetof(LumakeyContext, x)
181 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
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 },
190 AVFILTER_DEFINE_CLASS(lumakey);
192 AVFilter ff_vf_lumakey = {
194 .description = NULL_IF_CONFIG_SMALL("Turns a certain luma into transparency."),
195 .priv_size = sizeof(LumakeyContext),
196 .priv_class = &lumakey_class,
197 .query_formats = query_formats,
198 .inputs = lumakey_inputs,
199 .outputs = lumakey_outputs,
200 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SLICE_THREADS,