Question

我正在尝试使用Image Magick将PNG文件转换为BGR 565位图图像。我做了大量的研究，但未能得出答案。任何人都可以帮助我吗？

Answer 1

编译此C程序并将其作为“rgbtobgr565”

安装在搜索路径中

/* rgbtobgr565 - convert 24-bit RGB pixels to 16-bit BGR565 pixels

  Written in 2016 by Glenn Randers-Pehrson <glennrp@users.sf.net>

  To the extent possible under law, the author has dedicated all copyright
  and related and neighboring rights to this software to the public domain
  worldwide. This software is distributed without any warranty.
  See <http://creativecommons.org/publicdomain/zero/1.0/>. 

  Use with ImageMagick or GraphicsMagick to convert 24-bit RGB pixels
  to 16-bit BGR565 pixels, e.g.,

      magick file.png -depth 8 rgb:- | rgbtobgr565 > file.bgr565

  Note that the 16-bit pixels are written in network byte order (most
  significant byte first), with blue in the most significant bits and
  red in the least significant bits.

  ChangLog:
  Jan 2017: changed bgr565 from int to unsigned short (suggested by
             Steven Valsesia)
*/

#include <stdio.h>
int main()
{
    int red,green,blue;
    unsigned short bgr565;
    while (1) {
        red=getchar(); if (red == EOF) return (0);
        green=getchar(); if (green == EOF) return (1);
        blue=getchar(); if (blue == EOF) return (1);
        bgr565 = (unsigned short)(red * 31.0 / 255.0) |
                 (unsigned short)(green * 63.0 / 255.0) << 5 |
                 (unsigned short)(blue * 31.0 / 255.0) << 11;
            putchar((bgr565 >> 8) & 0xFF);
            putchar(bgr565 & 0xFF);
        }
    }

然后运行

magick file.png -depth 8 rgb:- | rgbtobgr565 > file.bgr565

为了完整性，这里是将bgr565像素转换回rgb的程序：

/* bgr565torgb - convert 16-bit BGR565 pixels to 24-bit RGB pixels

  Written in 2016 by Glenn Randers-Pehrson <glennrp@users.sf.net>

  To the extent possible under law, the author has dedicated all copyright
  and related and neighboring rights to this software to the public domain
  worldwide. This software is distributed without any warranty.
  See <http://creativecommons.org/publicdomain/zero/1.0/>. 

  Use with ImageMagick or GraphicsMagick to convert 16-bit BGR565 pixels
  to 24-bit RGB pixels, e.g.,

      bgr565torgb < file.bgr565 > file.rgb
      magick -size WxH -depth 8 file.rgb file.png 
*/

#include <stdio.h>
int main()
{
    int rgbhi,rgblo,red,green,blue;
    while (1) {
        rgbhi=getchar(); if (rgbhi == EOF) return (0);
        rgblo=getchar(); if (rgblo == EOF) return (1);
        putchar((rgblo & 0x1F) << 3 | (rgblo & 0x14) >> 3 );
        putchar((rgbhi & 0x07) << 5 |
                (rgblo & 0xE0) >> 3 |
                (rgbhi & 0x06) >> 1);
        putchar((rgbhi & 0xE0) | (rgbhi >> 5) & 0x07);
    }
}

如何使用ImageMagick将{PNG转换为BGR 565格式

1 个答案: