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path: root/libavfilter/vf_alphamerge.c (plain)
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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/pixfmt.h"
29#include "avfilter.h"
30#include "bufferqueue.h"
31#include "drawutils.h"
32#include "formats.h"
33#include "internal.h"
34#include "video.h"
35
36enum { Y, U, V, A };
37
38typedef struct {
39 int is_packed_rgb;
40 uint8_t rgba_map[4];
41 struct FFBufQueue queue_main;
42 struct FFBufQueue queue_alpha;
43} AlphaMergeContext;
44
45static av_cold void uninit(AVFilterContext *ctx)
46{
47 AlphaMergeContext *merge = ctx->priv;
48 ff_bufqueue_discard_all(&merge->queue_main);
49 ff_bufqueue_discard_all(&merge->queue_alpha);
50}
51
52static int query_formats(AVFilterContext *ctx)
53{
54 static const enum AVPixelFormat main_fmts[] = {
55 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
56 AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA, AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR,
57 AV_PIX_FMT_NONE
58 };
59 static const enum AVPixelFormat alpha_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
60 AVFilterFormats *main_formats = NULL, *alpha_formats = NULL;
61 int ret;
62
63 if (!(main_formats = ff_make_format_list(main_fmts)) ||
64 !(alpha_formats = ff_make_format_list(alpha_fmts))) {
65 ret = AVERROR(ENOMEM);
66 goto fail;
67 }
68 if ((ret = ff_formats_ref(main_formats , &ctx->inputs[0]->out_formats)) < 0 ||
69 (ret = ff_formats_ref(alpha_formats, &ctx->inputs[1]->out_formats)) < 0 ||
70 (ret = ff_formats_ref(main_formats , &ctx->outputs[0]->in_formats)) < 0)
71 goto fail;
72 return 0;
73fail:
74 if (main_formats)
75 av_freep(&main_formats->formats);
76 av_freep(&main_formats);
77 if (alpha_formats)
78 av_freep(&alpha_formats->formats);
79 av_freep(&alpha_formats);
80 return ret;
81}
82
83static int config_input_main(AVFilterLink *inlink)
84{
85 AlphaMergeContext *merge = inlink->dst->priv;
86 merge->is_packed_rgb =
87 ff_fill_rgba_map(merge->rgba_map, inlink->format) >= 0;
88 return 0;
89}
90
91static int config_output(AVFilterLink *outlink)
92{
93 AVFilterContext *ctx = outlink->src;
94 AVFilterLink *mainlink = ctx->inputs[0];
95 AVFilterLink *alphalink = ctx->inputs[1];
96 if (mainlink->w != alphalink->w || mainlink->h != alphalink->h) {
97 av_log(ctx, AV_LOG_ERROR,
98 "Input frame sizes do not match (%dx%d vs %dx%d).\n",
99 mainlink->w, mainlink->h,
100 alphalink->w, alphalink->h);
101 return AVERROR(EINVAL);
102 }
103
104 outlink->w = mainlink->w;
105 outlink->h = mainlink->h;
106 outlink->time_base = mainlink->time_base;
107 outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
108 outlink->frame_rate = mainlink->frame_rate;
109 return 0;
110}
111
112static void draw_frame(AVFilterContext *ctx,
113 AVFrame *main_buf,
114 AVFrame *alpha_buf)
115{
116 AlphaMergeContext *merge = ctx->priv;
117 int h = main_buf->height;
118
119 if (merge->is_packed_rgb) {
120 int x, y;
121 uint8_t *pin, *pout;
122 for (y = 0; y < h; y++) {
123 pin = alpha_buf->data[0] + y * alpha_buf->linesize[0];
124 pout = main_buf->data[0] + y * main_buf->linesize[0] + merge->rgba_map[A];
125 for (x = 0; x < main_buf->width; x++) {
126 *pout = *pin;
127 pin += 1;
128 pout += 4;
129 }
130 }
131 } else {
132 int y;
133 const int main_linesize = main_buf->linesize[A];
134 const int alpha_linesize = alpha_buf->linesize[Y];
135 for (y = 0; y < h && y < alpha_buf->height; y++) {
136 memcpy(main_buf->data[A] + y * main_linesize,
137 alpha_buf->data[Y] + y * alpha_linesize,
138 FFMIN(main_linesize, alpha_linesize));
139 }
140 }
141}
142
143static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
144{
145 AVFilterContext *ctx = inlink->dst;
146 AlphaMergeContext *merge = ctx->priv;
147
148 int ret = 0;
149 int is_alpha = (inlink == ctx->inputs[1]);
150 struct FFBufQueue *queue =
151 (is_alpha ? &merge->queue_alpha : &merge->queue_main);
152 ff_bufqueue_add(ctx, queue, buf);
153
154 do {
155 AVFrame *main_buf, *alpha_buf;
156
157 if (!ff_bufqueue_peek(&merge->queue_main, 0) ||
158 !ff_bufqueue_peek(&merge->queue_alpha, 0)) break;
159
160 main_buf = ff_bufqueue_get(&merge->queue_main);
161 alpha_buf = ff_bufqueue_get(&merge->queue_alpha);
162
163 draw_frame(ctx, main_buf, alpha_buf);
164 ret = ff_filter_frame(ctx->outputs[0], main_buf);
165 av_frame_free(&alpha_buf);
166 } while (ret >= 0);
167 return ret;
168}
169
170static int request_frame(AVFilterLink *outlink)
171{
172 AVFilterContext *ctx = outlink->src;
173 AlphaMergeContext *merge = ctx->priv;
174 int in, ret;
175
176 in = ff_bufqueue_peek(&merge->queue_main, 0) ? 1 : 0;
177 ret = ff_request_frame(ctx->inputs[in]);
178 if (ret < 0)
179 return ret;
180 return 0;
181}
182
183static const AVFilterPad alphamerge_inputs[] = {
184 {
185 .name = "main",
186 .type = AVMEDIA_TYPE_VIDEO,
187 .config_props = config_input_main,
188 .filter_frame = filter_frame,
189 .needs_writable = 1,
190 },{
191 .name = "alpha",
192 .type = AVMEDIA_TYPE_VIDEO,
193 .filter_frame = filter_frame,
194 },
195 { NULL }
196};
197
198static const AVFilterPad alphamerge_outputs[] = {
199 {
200 .name = "default",
201 .type = AVMEDIA_TYPE_VIDEO,
202 .config_props = config_output,
203 .request_frame = request_frame,
204 },
205 { NULL }
206};
207
208AVFilter ff_vf_alphamerge = {
209 .name = "alphamerge",
210 .description = NULL_IF_CONFIG_SMALL("Copy the luma value of the second "
211 "input into the alpha channel of the first input."),
212 .uninit = uninit,
213 .priv_size = sizeof(AlphaMergeContext),
214 .query_formats = query_formats,
215 .inputs = alphamerge_inputs,
216 .outputs = alphamerge_outputs,
217};
218
generated by cgit at 2024-05-17 01:45:31 (GMT)