声明: property scanline[row: integer]: pointer read getscanline ;(只读)
//以下函数把位图变也灰度（可调节）procedure graybitmap(abitmap: tbitmap; value: integer=0);var pixel: prgbtriple; //用来接收返回值 w, h: integer; x, y: integer; avg: integer;begin abitmap.pixelformat := pf24bit; w := abitmap.width; h := abitmap.height; for y := 0 to h - 1 do begin pixel := abitmap.scanline[y]; for x := 0 to w - 1 do begin avg := ((pixel^.rgbtred + pixel^.rgbtgreen + pixel^.rgbtblue) div 3)+ value; if avg > 240 then avg := 240; pixel^.rgbtred := avg; pixel^.rgbtgreen := avg; pixel^.rgbtblue := avg; inc(pixel); end; end;end;
附定义: prgbtriple = ^trgbtriple;
trgbtriple = tagrgbtriple;tagrgbtriple = packed record rgbtblue: byte; rgbtgreen: byte; rgbtred: byte;end;
