private (byte a, byte r, byte g, byte b) PoolMean3(LockBitmap4Pointer bitmap, int startX, int xLength, int startY, int yLength)
{
var a = 0;
var r = 0;
var g = 0;
var b = 0;
var index = 0;
for (var x = startX; x < startX + xLength && x < _width; x++)
{
for (var y = startY; y < startY + yLength && y < _height; y++)
{
var color = bitmap.GetPixel(x, y);
a += color.A;
r += color.R;
g += color.G;
b += color.B;
index++;
}
}
_valueSumOfColor[0] += a;
_valueSumOfColor[1] += r;
_valueSumOfColor[2] += g;
_valueSumOfColor[3] += b;
return((byte)(a / index), (byte)(r / index), (byte)(g / index), (byte)(b / index));
}
internal byte[,,] Execute(Bitmap bitmap, int compressionWidth, int compressionHeight, PoolingType poolingType)
{
_width = bitmap.Width;
_height = bitmap.Height;
if (_width < compressionWidth)
{
return(null);
}
if (_height < compressionHeight)
{
return(null);
}
// 倍数
var multipleX = _width / compressionWidth;
var multipleY = _height / compressionHeight;
var cWidth = (int)Math.Ceiling(_width / (float)multipleX);
var cHeight = (int)Math.Ceiling(_height / (float)multipleY);
var result = new byte[cWidth, cHeight, 4];
var lockbmp = new LockBitmap4Pointer(bitmap);
lockbmp.LockBits();
Parallel.For(0, cWidth, (cx) =>
{
//for (int cx = 0; cx < cWidth; cx++)
//{
Parallel.For(0, cHeight, (cy) =>
{
//for (int cy = 0; cy < cHeight; cy++)
//{
(byte a, byte r, byte g, byte b)data;
if (poolingType == PoolingType.Mean)
{
data = PoolMean3(lockbmp, cx * multipleX, multipleX, cy * multipleY, multipleY);
}
else
{
data = PoolMax3(lockbmp, cx * multipleX, multipleX, cy * multipleY, multipleY);
}
result[cx, cy, 0] = data.a;
result[cx, cy, 1] = data.r;
result[cx, cy, 2] = data.g;
result[cx, cy, 3] = data.b;
});
});
//从内存解锁Bitmap
lockbmp.UnlockBits();
return(result);
}
private float PoolMean(LockBitmap4Pointer bitmap, int startX, int xLength, int startY, int yLength)
{
var result = 0f;
var index = 0;
for (var x = startX; x < startX + xLength && x < _width; x++)
{
for (var y = startY; y < startY + yLength && y < _height; y++)
{
result += bitmap.GetPixel(x, y).ToArgb();//.GetBrightness();
index++;
}
}
_valueSum += result;
return(result / index);
}
private float PoolMax(LockBitmap4Pointer bitmap, int startX, int xLength, int startY, int yLength)
{
var result = 0f;
for (var x = startX; x < startX + xLength && x < _width; x++)
{
for (var y = startY; y < startY + yLength && y < _height; y++)
{
var light = Math.Abs(bitmap.GetPixel(x, y).ToArgb());//.GetBrightness();
if (result < light)
{
result = light;
}
_valueSum += light;
}
}
return(result);
}
private (byte a, byte r, byte g, byte b) PoolMax3(LockBitmap4Pointer bitmap, int startX, int xLength, int startY, int yLength)
{
var a = 0;
var r = 0;
var g = 0;
var b = 0;
for (var x = startX; x < startX + xLength && x < _width; x++)
{
for (var y = startY; y < startY + yLength && y < _height; y++)
{
var color = bitmap.GetPixel(x, y);
if (a < color.A)
{
a = color.A;
}
if (r < color.R)
{
r = color.R;
}
if (g < color.G)
{
g = color.G;
}
if (b < color.B)
{
b = color.B;
}
_valueSumOfColor[0] += color.A;
_valueSumOfColor[1] += color.R;
_valueSumOfColor[2] += color.G;
_valueSumOfColor[3] += color.B;
}
}
return((byte)a, (byte)r, (byte)g, (byte)b);
}
