libavfilter/vf_drawbox.c

   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
  21 /**
  22  * @file
  23  * Box drawing filter. Also a nice template for a filter that needs to
  24  * write in the input frame.
  25  */
  26
  27 #include "libavutil/colorspace.h"
  28 #include "libavutil/common.h"
  29 #include "libavutil/pixdesc.h"
  30 #include "libavutil/parseutils.h"
  31 #include "avfilter.h"
  32 #include "formats.h"
  33 #include "internal.h"
  34 #include "video.h"
  35
  36 enum { Y, U, V, A };
  37
  38 typedef struct {
  39     int x, y, w, h;
  40     unsigned char yuv_color[4];
  41     int vsub, hsub;   ///< chroma subsampling
  42 } DrawBoxContext;
  43
  44 static av_cold int init(AVFilterContext *ctx, const char *args)
  45 {
  46     DrawBoxContext *drawbox= ctx->priv;
  47     char color_str[1024] = "black";
  48     uint8_t rgba_color[4];
  49
  50     drawbox->x = drawbox->y = drawbox->w = drawbox->h = 0;
  51
  52     if (args)
  53         sscanf(args, "%d:%d:%d:%d:%s",
  54                &drawbox->x, &drawbox->y, &drawbox->w, &drawbox->h, color_str);
  55
  56     if (av_parse_color(rgba_color, color_str, -1, ctx) < 0)
  57         return AVERROR(EINVAL);
  58
  59     drawbox->yuv_color[Y] = RGB_TO_Y_CCIR(rgba_color[0], rgba_color[1], rgba_color[2]);
  60     drawbox->yuv_color[U] = RGB_TO_U_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
  61     drawbox->yuv_color[V] = RGB_TO_V_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
  62     drawbox->yuv_color[A] = rgba_color[3];
  63
  64     return 0;
  65 }
  66
  67 static int query_formats(AVFilterContext *ctx)
  68 {
  69     enum AVPixelFormat pix_fmts[] = {
  70         AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV420P,
  71         AV_PIX_FMT_YUV411P,  AV_PIX_FMT_YUV410P,
  72         AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
  73         AV_PIX_FMT_YUV440P,  AV_PIX_FMT_YUVJ440P,
  74         AV_PIX_FMT_NONE
  75     };
  76
  77     ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
  78     return 0;
  79 }
  80
  81 static int config_input(AVFilterLink *inlink)
  82 {
  83     DrawBoxContext *drawbox = inlink->dst->priv;
  84     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
  85
  86     drawbox->hsub = desc->log2_chroma_w;
  87     drawbox->vsub = desc->log2_chroma_h;
  88
  89     if (drawbox->w == 0) drawbox->w = inlink->w;
  90     if (drawbox->h == 0) drawbox->h = inlink->h;
  91
  92     av_log(inlink->dst, AV_LOG_VERBOSE, "x:%d y:%d w:%d h:%d color:0x%02X%02X%02X%02X\n",
  93            drawbox->w, drawbox->y, drawbox->w, drawbox->h,
  94            drawbox->yuv_color[Y], drawbox->yuv_color[U], drawbox->yuv_color[V], drawbox->yuv_color[A]);
  95
  96     return 0;
  97 }
  98
  99 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
 100 {
 101     DrawBoxContext *drawbox = inlink->dst->priv;
 102     int plane, x, y, xb = drawbox->x, yb = drawbox->y;
 103     unsigned char *row[4];
 104
 105     for (y = FFMAX(yb, 0); y < frame->height && y < (yb + drawbox->h); y++) {
 106         row[0] = frame->data[0] + y * frame->linesize[0];
 107
 108         for (plane = 1; plane < 3; plane++)
 109             row[plane] = frame->data[plane] +
 110                  frame->linesize[plane] * (y >> drawbox->vsub);
 111
 112         for (x = FFMAX(xb, 0); x < (xb + drawbox->w) && x < frame->width; x++) {
 113             double alpha = (double)drawbox->yuv_color[A] / 255;
 114
 115             if ((y - yb < 3) || (yb + drawbox->h - y < 4) ||
 116                 (x - xb < 3) || (xb + drawbox->w - x < 4)) {
 117                 row[0][x                 ] = (1 - alpha) * row[0][x                 ] + alpha * drawbox->yuv_color[Y];
 118                 row[1][x >> drawbox->hsub] = (1 - alpha) * row[1][x >> drawbox->hsub] + alpha * drawbox->yuv_color[U];
 119                 row[2][x >> drawbox->hsub] = (1 - alpha) * row[2][x >> drawbox->hsub] + alpha * drawbox->yuv_color[V];
 120             }
 121         }
 122     }
 123
 124     return ff_filter_frame(inlink->dst->outputs[0], frame);
 125 }
 126
 127 static const AVFilterPad avfilter_vf_drawbox_inputs[] = {
 128     {
 129         .name             = "default",
 130         .type             = AVMEDIA_TYPE_VIDEO,
 131         .config_props     = config_input,
 132         .get_video_buffer = ff_null_get_video_buffer,
 133         .filter_frame     = filter_frame,
 134         .needs_writable   = 1,
 135     },
 136     { NULL }
 137 };
 138
 139 static const AVFilterPad avfilter_vf_drawbox_outputs[] = {
 140     {
 141         .name = "default",
 142         .type = AVMEDIA_TYPE_VIDEO,
 143     },
 144     { NULL }
 145 };
 146
 147 AVFilter avfilter_vf_drawbox = {
 148     .name      = "drawbox",
 149     .description = NULL_IF_CONFIG_SMALL("Draw a colored box on the input video."),
 150     .priv_size = sizeof(DrawBoxContext),
 151     .init      = init,
 152
 153     .query_formats   = query_formats,
 154     .inputs    = avfilter_vf_drawbox_inputs,
 155     .outputs   = avfilter_vf_drawbox_outputs,
 156 };