Libav 0.7.1
libavfilter/vf_drawbox.c
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00001 /*
00002  * Copyright (c) 2008 Affine Systems, Inc (Michael Sullivan, Bobby Impollonia)
00003  *
00004  * This file is part of Libav.
00005  *
00006  * Libav is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * Libav is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with Libav; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00027 #include "libavutil/colorspace.h"
00028 #include "libavutil/pixdesc.h"
00029 #include "libavutil/parseutils.h"
00030 #include "avfilter.h"
00031 
00032 enum { Y, U, V, A };
00033 
00034 typedef struct {
00035     int x, y, w, h;
00036     unsigned char yuv_color[4];
00037     int vsub, hsub;   //< chroma subsampling
00038 } DrawBoxContext;
00039 
00040 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00041 {
00042     DrawBoxContext *drawbox= ctx->priv;
00043     char color_str[1024] = "black";
00044     uint8_t rgba_color[4];
00045 
00046     drawbox->x = drawbox->y = drawbox->w = drawbox->h = 0;
00047 
00048     if (args)
00049         sscanf(args, "%d:%d:%d:%d:%s",
00050                &drawbox->x, &drawbox->y, &drawbox->w, &drawbox->h, color_str);
00051 
00052     if (av_parse_color(rgba_color, color_str, -1, ctx) < 0)
00053         return AVERROR(EINVAL);
00054 
00055     drawbox->yuv_color[Y] = RGB_TO_Y_CCIR(rgba_color[0], rgba_color[1], rgba_color[2]);
00056     drawbox->yuv_color[U] = RGB_TO_U_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
00057     drawbox->yuv_color[V] = RGB_TO_V_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
00058     drawbox->yuv_color[A] = rgba_color[3];
00059 
00060     return 0;
00061 }
00062 
00063 static int query_formats(AVFilterContext *ctx)
00064 {
00065     enum PixelFormat pix_fmts[] = {
00066         PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P,
00067         PIX_FMT_YUV411P,  PIX_FMT_YUV410P,
00068         PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,
00069         PIX_FMT_YUV440P,  PIX_FMT_YUVJ440P,
00070         PIX_FMT_NONE
00071     };
00072 
00073     avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
00074     return 0;
00075 }
00076 
00077 static int config_input(AVFilterLink *inlink)
00078 {
00079     DrawBoxContext *drawbox = inlink->dst->priv;
00080 
00081     drawbox->hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
00082     drawbox->vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
00083 
00084     if (drawbox->w == 0) drawbox->w = inlink->w;
00085     if (drawbox->h == 0) drawbox->h = inlink->h;
00086 
00087     av_log(inlink->dst, AV_LOG_INFO, "x:%d y:%d w:%d h:%d color:0x%02X%02X%02X%02X\n",
00088            drawbox->w, drawbox->y, drawbox->w, drawbox->h,
00089            drawbox->yuv_color[Y], drawbox->yuv_color[U], drawbox->yuv_color[V], drawbox->yuv_color[A]);
00090 
00091     return 0;
00092 }
00093 
00094 static void draw_slice(AVFilterLink *inlink, int y0, int h, int slice_dir)
00095 {
00096     DrawBoxContext *drawbox = inlink->dst->priv;
00097     int plane, x, y, xb = drawbox->x, yb = drawbox->y;
00098     unsigned char *row[4];
00099     AVFilterBufferRef *picref = inlink->cur_buf;
00100 
00101     for (y = FFMAX(yb, y0); y < (y0 + h) && y < (yb + drawbox->h); y++) {
00102         row[0] = picref->data[0] + y * picref->linesize[0];
00103 
00104         for (plane = 1; plane < 3; plane++)
00105             row[plane] = picref->data[plane] +
00106                 picref->linesize[plane] * (y >> drawbox->vsub);
00107 
00108         for (x = FFMAX(xb, 0); x < (xb + drawbox->w) && x < picref->video->w; x++) {
00109             double alpha = (double)drawbox->yuv_color[A] / 255;
00110 
00111             if ((y - yb < 3) || (yb + drawbox->h - y < 4) ||
00112                 (x - xb < 3) || (xb + drawbox->w - x < 4)) {
00113                 row[0][x                 ] = (1 - alpha) * row[0][x                 ] + alpha * drawbox->yuv_color[Y];
00114                 row[1][x >> drawbox->hsub] = (1 - alpha) * row[1][x >> drawbox->hsub] + alpha * drawbox->yuv_color[U];
00115                 row[2][x >> drawbox->hsub] = (1 - alpha) * row[2][x >> drawbox->hsub] + alpha * drawbox->yuv_color[V];
00116             }
00117         }
00118     }
00119 
00120     avfilter_draw_slice(inlink->dst->outputs[0], y0, h, 1);
00121 }
00122 
00123 AVFilter avfilter_vf_drawbox = {
00124     .name      = "drawbox",
00125     .description = NULL_IF_CONFIG_SMALL("Draw a colored box on the input video."),
00126     .priv_size = sizeof(DrawBoxContext),
00127     .init      = init,
00128 
00129     .query_formats   = query_formats,
00130     .inputs    = (AVFilterPad[]) {{ .name             = "default",
00131                                     .type             = AVMEDIA_TYPE_VIDEO,
00132                                     .config_props     = config_input,
00133                                     .get_video_buffer = avfilter_null_get_video_buffer,
00134                                     .start_frame      = avfilter_null_start_frame,
00135                                     .draw_slice       = draw_slice,
00136                                     .end_frame        = avfilter_null_end_frame,
00137                                     .min_perms        = AV_PERM_WRITE | AV_PERM_READ,
00138                                     .rej_perms        = AV_PERM_PRESERVE },
00139                                   { .name = NULL}},
00140     .outputs   = (AVFilterPad[]) {{ .name             = "default",
00141                                     .type             = AVMEDIA_TYPE_VIDEO, },
00142                                   { .name = NULL}},
00143 };