vf_drawbox.c
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1 /*
2  * Copyright (c) 2008 Affine Systems, Inc (Michael Sullivan, Bobby Impollonia)
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
27 #include "libavutil/colorspace.h"
28 #include "libavutil/pixdesc.h"
29 #include "libavutil/parseutils.h"
30 #include "avfilter.h"
31 
32 enum { Y, U, V, A };
33 
34 typedef struct {
35  int x, y, w, h;
36  unsigned char yuv_color[4];
37  int vsub, hsub;
39 
40 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
41 {
43  char color_str[1024] = "black";
44  uint8_t rgba_color[4];
45 
46  drawbox->x = drawbox->y = drawbox->w = drawbox->h = 0;
47 
48  if (args)
49  sscanf(args, "%d:%d:%d:%d:%s",
50  &drawbox->x, &drawbox->y, &drawbox->w, &drawbox->h, color_str);
51 
52  if (av_parse_color(rgba_color, color_str, -1, ctx) < 0)
53  return AVERROR(EINVAL);
54 
55  drawbox->yuv_color[Y] = RGB_TO_Y_CCIR(rgba_color[0], rgba_color[1], rgba_color[2]);
56  drawbox->yuv_color[U] = RGB_TO_U_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
57  drawbox->yuv_color[V] = RGB_TO_V_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
58  drawbox->yuv_color[A] = rgba_color[3];
59 
60  return 0;
61 }
62 
64 {
65  enum PixelFormat pix_fmts[] = {
71  };
72 
74  return 0;
75 }
76 
77 static int config_input(AVFilterLink *inlink)
78 {
79  DrawBoxContext *drawbox = inlink->dst->priv;
80 
81  drawbox->hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
82  drawbox->vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
83 
84  if (drawbox->w == 0) drawbox->w = inlink->w;
85  if (drawbox->h == 0) drawbox->h = inlink->h;
86 
87  av_log(inlink->dst, AV_LOG_INFO, "x:%d y:%d w:%d h:%d color:0x%02X%02X%02X%02X\n",
88  drawbox->w, drawbox->y, drawbox->w, drawbox->h,
89  drawbox->yuv_color[Y], drawbox->yuv_color[U], drawbox->yuv_color[V], drawbox->yuv_color[A]);
90 
91  return 0;
92 }
93 
94 static void draw_slice(AVFilterLink *inlink, int y0, int h, int slice_dir)
95 {
96  DrawBoxContext *drawbox = inlink->dst->priv;
97  int plane, x, y, xb = drawbox->x, yb = drawbox->y;
98  unsigned char *row[4];
99  AVFilterBufferRef *picref = inlink->cur_buf;
100 
101  for (y = FFMAX(yb, y0); y < (y0 + h) && y < (yb + drawbox->h); y++) {
102  row[0] = picref->data[0] + y * picref->linesize[0];
103 
104  for (plane = 1; plane < 3; plane++)
105  row[plane] = picref->data[plane] +
106  picref->linesize[plane] * (y >> drawbox->vsub);
107 
108  for (x = FFMAX(xb, 0); x < (xb + drawbox->w) && x < picref->video->w; x++) {
109  double alpha = (double)drawbox->yuv_color[A] / 255;
110 
111  if ((y - yb < 3) || (yb + drawbox->h - y < 4) ||
112  (x - xb < 3) || (xb + drawbox->w - x < 4)) {
113  row[0][x ] = (1 - alpha) * row[0][x ] + alpha * drawbox->yuv_color[Y];
114  row[1][x >> drawbox->hsub] = (1 - alpha) * row[1][x >> drawbox->hsub] + alpha * drawbox->yuv_color[U];
115  row[2][x >> drawbox->hsub] = (1 - alpha) * row[2][x >> drawbox->hsub] + alpha * drawbox->yuv_color[V];
116  }
117  }
118  }
119 
120  avfilter_draw_slice(inlink->dst->outputs[0], y0, h, 1);
121 }
122 
124  .name = "drawbox",
125  .description = NULL_IF_CONFIG_SMALL("Draw a colored box on the input video."),
126  .priv_size = sizeof(DrawBoxContext),
127  .init = init,
128 
130  .inputs = (AVFilterPad[]) {{ .name = "default",
131  .type = AVMEDIA_TYPE_VIDEO,
132  .config_props = config_input,
133  .get_video_buffer = avfilter_null_get_video_buffer,
134  .start_frame = avfilter_null_start_frame,
135  .draw_slice = draw_slice,
136  .end_frame = avfilter_null_end_frame,
137  .min_perms = AV_PERM_WRITE | AV_PERM_READ,
138  .rej_perms = AV_PERM_PRESERVE },
139  { .name = NULL}},
140  .outputs = (AVFilterPad[]) {{ .name = "default",
141  .type = AVMEDIA_TYPE_VIDEO, },
142  { .name = NULL}},
143 };