VB实例编程：VB6把彩色图片变成灰阶的方法_第2页

　　’旋转
　　For Y = 1 To tSBmpInfo.bmHeight
　　For x = 1 To tSBmpInfo.bmWidth
　　b = (x - 1) * BytesPixel + 1
　　l = sBits(b, Y) * 0.114 + sBits(b + 1, Y) * 0.587 + sBits(b + 2, Y) * 0.299
　　dBits(b, Y) = l
　　dBits(b + 1, Y) = l
　　dBits(b + 2, Y) = l
　　’l = dBits((x - 1) * BytesPixel + 1, Y) * 0.114 + dBits((x - 1) * BytesPixel + 2, Y) * 0.587 + dBits((x - 1) * BytesPixel + 3, Y) * 0.299
　　’dBits((x - 1) * BytesPixel + 1, Y) = l
　　’dBits((x - 1) * BytesPixel + 2, Y) = l
　　’dBits((x - 1) * BytesPixel + 3, Y) = l
　　Next x
　　Next Y
　　Call SetBitmapBits(hDestBmp, tDBmpInfo.bmWidthBytes * tDBmpInfo.bmHeight, dBits(1, 1))
　　End Function
　　’算法2.2 提高速度约2秒 是全国计算机等级考试网，加入收藏方法1的46倍速度 参数不一样
　　Public Function TurnPicGray(hSrcBmp As Long) As Boolean
　　Dim x As Long, Y As Long
　　Dim BytesPixel As Long
　　Dim tSBmpInfo As BITMAP
　　Dim sBits() As Byte
　　’获得位图信息
　　Call GetObject(hSrcBmp, Len(tSBmpInfo), tSBmpInfo)
　　’申请空间
　　ReDim sBits(1 To tSBmpInfo.bmWidthBytes, 1 To tSBmpInfo.bmHeight)
　　’获得源图与目标图二进制位
　　Call GetBitmapBits(hSrcBmp, tSBmpInfo.bmWidthBytes * tSBmpInfo.bmHeight, sBits(1, 1))
　　’计算颜色值占用多少字节
　　BytesPixel = tSBmpInfo.bmBitsPixel / 8
　　Dim l As Integer
　　Dim b As Long
　　’旋转
　　For Y = 1 To tSBmpInfo.bmHeight
　　For x = 1 To tSBmpInfo.bmWidth
　　b = (x - 1) * BytesPixel + 1
　　l = sBits(b, Y) * 0.114 + sBits(b + 1, Y) * 0.587 + sBits(b + 2, Y) * 0.299
　　sBits(b, Y) = l
　　sBits(b + 1, Y) = l
　　sBits(b + 2, Y) = l
　　Next x
　　Next Y
　　Call SetBitmapBits(hSrcBmp, tSBmpInfo.bmWidthBytes * tSBmpInfo.bmHeight, sBits(1, 1))
　　End Function
　　’算法
　　Public Sub SetPicGray(Pic As PictureBox)
　　Dim width5 As Long, heigh5 As Long, rgb5 As Long
　　Dim hdc5 As Long, i As Long, j As Long