1 /*
2 * Copyright (c) 2012 Steven Robertson
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 /**
22 * @file
23 * copy an alpha component from another video's luma
24 */
25
26 #include <string.h>
27
28 #include "libavutil/imgutils.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/pixfmt.h"
31 #include "avfilter.h"
32 #include "drawutils.h"
33 #include "formats.h"
34 #include "filters.h"
35 #include "framesync.h"
36 #include "internal.h"
37 #include "video.h"
38
39 enum { Y, U, V, A };
40
41 typedef struct AlphaMergeContext {
42 const AVClass *class;
43
44 int is_packed_rgb;
45 uint8_t rgba_map[4];
46
47 FFFrameSync fs;
48 } AlphaMergeContext;
49
do_alphamerge(FFFrameSync * fs)50 static int do_alphamerge(FFFrameSync *fs)
51 {
52 AVFilterContext *ctx = fs->parent;
53 AlphaMergeContext *s = ctx->priv;
54 AVFrame *main_buf, *alpha_buf;
55 int ret;
56
57 ret = ff_framesync_dualinput_get_writable(fs, &main_buf, &alpha_buf);
58 if (ret < 0)
59 return ret;
60 if (!alpha_buf)
61 return ff_filter_frame(ctx->outputs[0], main_buf);
62
63 if (s->is_packed_rgb) {
64 int x, y;
65 uint8_t *pin, *pout;
66 for (y = 0; y < main_buf->height; y++) {
67 pin = alpha_buf->data[0] + y * alpha_buf->linesize[0];
68 pout = main_buf->data[0] + y * main_buf->linesize[0] + s->rgba_map[A];
69 for (x = 0; x < main_buf->width; x++) {
70 *pout = *pin;
71 pin += 1;
72 pout += 4;
73 }
74 }
75 } else {
76 const int main_linesize = main_buf->linesize[A];
77 const int alpha_linesize = alpha_buf->linesize[Y];
78 av_image_copy_plane(main_buf->data[A], main_linesize,
79 alpha_buf->data[Y], alpha_linesize,
80 FFMIN(main_linesize, alpha_linesize), alpha_buf->height);
81 }
82
83 return ff_filter_frame(ctx->outputs[0], main_buf);
84 }
85
init(AVFilterContext * ctx)86 static av_cold int init(AVFilterContext *ctx)
87 {
88 AlphaMergeContext *s = ctx->priv;
89
90 s->fs.on_event = do_alphamerge;
91 return 0;
92 }
93
query_formats(AVFilterContext * ctx)94 static int query_formats(AVFilterContext *ctx)
95 {
96 static const enum AVPixelFormat main_fmts[] = {
97 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
98 AV_PIX_FMT_GBRAP,
99 AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA, AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR,
100 AV_PIX_FMT_NONE
101 };
102 static const enum AVPixelFormat alpha_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
103 AVFilterFormats *main_formats = ff_make_format_list(main_fmts);
104 int ret;
105
106 if ((ret = ff_formats_ref(main_formats, &ctx->inputs[0]->outcfg.formats)) < 0 ||
107 (ret = ff_formats_ref(main_formats, &ctx->outputs[0]->incfg.formats)) < 0)
108 return ret;
109
110 return ff_formats_ref(ff_make_format_list(alpha_fmts),
111 &ctx->inputs[1]->outcfg.formats);
112 }
113
config_input_main(AVFilterLink * inlink)114 static int config_input_main(AVFilterLink *inlink)
115 {
116 AlphaMergeContext *s = inlink->dst->priv;
117 s->is_packed_rgb =
118 ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0 &&
119 inlink->format != AV_PIX_FMT_GBRAP;
120 return 0;
121 }
122
config_output(AVFilterLink * outlink)123 static int config_output(AVFilterLink *outlink)
124 {
125 AVFilterContext *ctx = outlink->src;
126 AlphaMergeContext *s = ctx->priv;
127 AVFilterLink *mainlink = ctx->inputs[0];
128 AVFilterLink *alphalink = ctx->inputs[1];
129 int ret;
130
131 if (mainlink->w != alphalink->w || mainlink->h != alphalink->h) {
132 av_log(ctx, AV_LOG_ERROR,
133 "Input frame sizes do not match (%dx%d vs %dx%d).\n",
134 mainlink->w, mainlink->h,
135 alphalink->w, alphalink->h);
136 return AVERROR(EINVAL);
137 }
138
139 if ((ret = ff_framesync_init_dualinput(&s->fs, ctx)) < 0)
140 return ret;
141
142 outlink->w = mainlink->w;
143 outlink->h = mainlink->h;
144 outlink->time_base = mainlink->time_base;
145 outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
146 outlink->frame_rate = mainlink->frame_rate;
147
148 return ff_framesync_configure(&s->fs);
149 }
150
activate(AVFilterContext * ctx)151 static int activate(AVFilterContext *ctx)
152 {
153 AlphaMergeContext *s = ctx->priv;
154 return ff_framesync_activate(&s->fs);
155 }
156
uninit(AVFilterContext * ctx)157 static av_cold void uninit(AVFilterContext *ctx)
158 {
159 AlphaMergeContext *s = ctx->priv;
160
161 ff_framesync_uninit(&s->fs);
162 }
163
164 static const AVFilterPad alphamerge_inputs[] = {
165 {
166 .name = "main",
167 .type = AVMEDIA_TYPE_VIDEO,
168 .config_props = config_input_main,
169 },{
170 .name = "alpha",
171 .type = AVMEDIA_TYPE_VIDEO,
172 },
173 };
174
175 static const AVFilterPad alphamerge_outputs[] = {
176 {
177 .name = "default",
178 .type = AVMEDIA_TYPE_VIDEO,
179 .config_props = config_output,
180 },
181 };
182
183 static const AVOption alphamerge_options[] = {
184 { NULL }
185 };
186
187 FRAMESYNC_DEFINE_CLASS(alphamerge, AlphaMergeContext, fs);
188
189 const AVFilter ff_vf_alphamerge = {
190 .name = "alphamerge",
191 .description = NULL_IF_CONFIG_SMALL("Copy the luma value of the second "
192 "input into the alpha channel of the first input."),
193 .preinit = alphamerge_framesync_preinit,
194 .priv_size = sizeof(AlphaMergeContext),
195 .priv_class = &alphamerge_class,
196 .init = init,
197 FILTER_INPUTS(alphamerge_inputs),
198 FILTER_OUTPUTS(alphamerge_outputs),
199 FILTER_QUERY_FUNC(query_formats),
200 .uninit = uninit,
201 .activate = activate,
202 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
203 };
204