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 "internal.h"
36 #include "video.h"
37
38 enum { Y, U, V, A };
39
40 typedef struct AlphaMergeContext {
41 const AVClass *class;
42
43 int is_packed_rgb;
44 uint8_t rgba_map[4];
45 AVFrame *main_frame;
46 AVFrame *alpha_frame;
47 } AlphaMergeContext;
48
query_formats(AVFilterContext * ctx)49 static int query_formats(AVFilterContext *ctx)
50 {
51 static const enum AVPixelFormat main_fmts[] = {
52 AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
53 AV_PIX_FMT_GBRAP,
54 AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA, AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR,
55 AV_PIX_FMT_NONE
56 };
57 static const enum AVPixelFormat alpha_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
58 AVFilterFormats *main_formats = NULL, *alpha_formats = NULL;
59 int ret;
60
61 if (!(main_formats = ff_make_format_list(main_fmts)) ||
62 !(alpha_formats = ff_make_format_list(alpha_fmts))) {
63 ret = AVERROR(ENOMEM);
64 goto fail;
65 }
66 if ((ret = ff_formats_ref(main_formats , &ctx->inputs[0]->out_formats)) < 0 ||
67 (ret = ff_formats_ref(alpha_formats, &ctx->inputs[1]->out_formats)) < 0 ||
68 (ret = ff_formats_ref(main_formats , &ctx->outputs[0]->in_formats)) < 0)
69 goto fail;
70 return 0;
71 fail:
72 if (main_formats)
73 av_freep(&main_formats->formats);
74 av_freep(&main_formats);
75 if (alpha_formats)
76 av_freep(&alpha_formats->formats);
77 av_freep(&alpha_formats);
78 return ret;
79 }
80
config_input_main(AVFilterLink * inlink)81 static int config_input_main(AVFilterLink *inlink)
82 {
83 AlphaMergeContext *s = inlink->dst->priv;
84 s->is_packed_rgb =
85 ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0 &&
86 inlink->format != AV_PIX_FMT_GBRAP;
87 return 0;
88 }
89
config_output(AVFilterLink * outlink)90 static int config_output(AVFilterLink *outlink)
91 {
92 AVFilterContext *ctx = outlink->src;
93 AVFilterLink *mainlink = ctx->inputs[0];
94 AVFilterLink *alphalink = ctx->inputs[1];
95 if (mainlink->w != alphalink->w || mainlink->h != alphalink->h) {
96 av_log(ctx, AV_LOG_ERROR,
97 "Input frame sizes do not match (%dx%d vs %dx%d).\n",
98 mainlink->w, mainlink->h,
99 alphalink->w, alphalink->h);
100 return AVERROR(EINVAL);
101 }
102
103 outlink->w = mainlink->w;
104 outlink->h = mainlink->h;
105 outlink->time_base = mainlink->time_base;
106 outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
107 outlink->frame_rate = mainlink->frame_rate;
108 return 0;
109 }
110
draw_frame(AVFilterContext * ctx,AVFrame * main_buf,AVFrame * alpha_buf)111 static void draw_frame(AVFilterContext *ctx,
112 AVFrame *main_buf,
113 AVFrame *alpha_buf)
114 {
115 AlphaMergeContext *s = ctx->priv;
116 int h = main_buf->height;
117
118 if (s->is_packed_rgb) {
119 int x, y;
120 uint8_t *pin, *pout;
121 for (y = 0; y < h; y++) {
122 pin = alpha_buf->data[0] + y * alpha_buf->linesize[0];
123 pout = main_buf->data[0] + y * main_buf->linesize[0] + s->rgba_map[A];
124 for (x = 0; x < main_buf->width; x++) {
125 *pout = *pin;
126 pin += 1;
127 pout += 4;
128 }
129 }
130 } else {
131 const int main_linesize = main_buf->linesize[A];
132 const int alpha_linesize = alpha_buf->linesize[Y];
133 av_image_copy_plane(main_buf->data[A], main_linesize,
134 alpha_buf->data[Y], alpha_linesize,
135 FFMIN(main_linesize, alpha_linesize), alpha_buf->height);
136 }
137 }
138
activate(AVFilterContext * ctx)139 static int activate(AVFilterContext *ctx)
140 {
141 AVFilterLink *outlink = ctx->outputs[0];
142 AlphaMergeContext *s = ctx->priv;
143 int ret;
144
145 FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, ctx);
146
147 if (!s->main_frame) {
148 ret = ff_inlink_consume_frame(ctx->inputs[0], &s->main_frame);
149 if (ret < 0)
150 return ret;
151 }
152
153 if (!s->alpha_frame) {
154 ret = ff_inlink_consume_frame(ctx->inputs[1], &s->alpha_frame);
155 if (ret < 0)
156 return ret;
157 }
158
159 if (s->main_frame && s->alpha_frame) {
160 if (!ctx->is_disabled)
161 draw_frame(ctx, s->main_frame, s->alpha_frame);
162 ret = ff_filter_frame(outlink, s->main_frame);
163 av_frame_free(&s->alpha_frame);
164 s->main_frame = NULL;
165 return ret;
166 }
167
168 FF_FILTER_FORWARD_STATUS(ctx->inputs[0], outlink);
169 FF_FILTER_FORWARD_STATUS(ctx->inputs[1], outlink);
170
171 if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
172 !ff_outlink_get_status(ctx->inputs[0]) &&
173 !s->main_frame) {
174 ff_inlink_request_frame(ctx->inputs[0]);
175 return 0;
176 }
177
178 if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
179 !ff_outlink_get_status(ctx->inputs[1]) &&
180 !s->alpha_frame) {
181 ff_inlink_request_frame(ctx->inputs[1]);
182 return 0;
183 }
184
185 return FFERROR_NOT_READY;
186 }
187
188 static const AVFilterPad alphamerge_inputs[] = {
189 {
190 .name = "main",
191 .type = AVMEDIA_TYPE_VIDEO,
192 .config_props = config_input_main,
193 .needs_writable = 1,
194 },{
195 .name = "alpha",
196 .type = AVMEDIA_TYPE_VIDEO,
197 },
198 { NULL }
199 };
200
201 static const AVFilterPad alphamerge_outputs[] = {
202 {
203 .name = "default",
204 .type = AVMEDIA_TYPE_VIDEO,
205 .config_props = config_output,
206 },
207 { NULL }
208 };
209
210 static const AVOption alphamerge_options[] = {
211 { NULL }
212 };
213
214 AVFILTER_DEFINE_CLASS(alphamerge);
215
216 AVFilter ff_vf_alphamerge = {
217 .name = "alphamerge",
218 .description = NULL_IF_CONFIG_SMALL("Copy the luma value of the second "
219 "input into the alpha channel of the first input."),
220 .priv_size = sizeof(AlphaMergeContext),
221 .priv_class = &alphamerge_class,
222 .query_formats = query_formats,
223 .inputs = alphamerge_inputs,
224 .outputs = alphamerge_outputs,
225 .activate = activate,
226 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
227 };
228