/// <summary>
/// 補完した値を求める
/// </summary>
/// <param name="bmpByte">BitmapDataのバイト配列</param>
/// <param name="x">変形後の位置 x</param>
/// <param name="y">変形後の位置 y</param>
/// <param name="pxCol">求めた色情報</param>
/// <returns>true:補完成功, false:対象座標は形状外部</returns>
private static bool Interpolate(BitmapByte bmpByte, double x, double y, ref Color pxCol)
{
int x0 = (int)(x + 0.5);
int y0 = (int)(y + 0.5);
if (x0 < 0 || bmpByte.Width <= x0 || y0 < 0 || bmpByte.Height <= y0)
{
return(false); // 対象座標は形状外部
}
pxCol = GetPixelByte(bmpByte, x0, y0);
return(true);
}
/// <summary>
/// BitmapDataのバイト配列対象のピクセルに色情報を設定
/// </summary>
/// <param name="bmpByte">BitmapDataのバイト配列情報</param>
/// <param name="x">対象のx座標</param>
/// <param name="y">対象のy座標</param>
/// <param name="col">設定する色情報</param>
private static void SetPixelByte(BitmapByte bmpByte, int x, int y, Color col)
{
int pos = x * bmpByte.DepthByte + bmpByte.Stride * y;
bmpByte.PixelBytes[pos + 0] = col.B;
bmpByte.PixelBytes[pos + 1] = col.G;
bmpByte.PixelBytes[pos + 2] = col.R;
if (bmpByte.DepthByte == 4)
{
bmpByte.PixelBytes[pos + 3] = col.A;
}
}
/// <summary>
/// BitmapDataのバイト配列よりピクセル情報を取得
/// </summary>
/// <param name="bmpByte">BitmapDataのバイト配列情報</param>
/// <param name="x">対象のx座標</param>
/// <param name="y">対象のy座標</param>
/// <returns>対象ピクセルの色情報</returns>
private static Color GetPixelByte(BitmapByte bmpByte, int x, int y)
{
int pos = x * bmpByte.DepthByte + bmpByte.Stride * y;
byte b = bmpByte.PixelBytes[pos + 0];
byte g = bmpByte.PixelBytes[pos + 1];
byte r = bmpByte.PixelBytes[pos + 2];
byte a = 255;
if (bmpByte.DepthByte == 4)
{
a = bmpByte.PixelBytes[pos + 3];
}
return(Color.FromArgb(a, r, g, b));
}
/// <summary>
/// 変形処理
/// </summary>
/// <param name="srcImg">元画像</param>
/// <param name="destImg">[out] 変形後画像</param>
/// <param name="pt">変形後画像の頂点情報</param>
/// <returns>true:成功, false:失敗</returns>
public static bool Transform(Bitmap srcImg, out Bitmap destImg, List <Point> pt)
{
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
sw.Reset();
sw.Start();
destImg = null;
BitmapByte srcByte = new BitmapByte();
BitmapByte destByte = new BitmapByte();
Color pxCol = Color.FromArgb(0, 0, 0, 0);
Color bgCol = Color.FromArgb(0, 0, 0, 0);
TfParam p = new TfParam();
int calcWidth, calcHeight;
int destWidth, destHeight;
double xa, ya, xb, yb, xc, yc, xd, yd;
double s, t; // 対象画素の元画像に対する比率 (0 <= s,t <=1)
double tx, ty; // 変形後の座標
try
{
destWidth = pt[0].X;
destHeight = pt[0].Y;;
for (int i = 1; i < pt.Count; i++)
{
if (destWidth < pt[i].X)
{
destWidth = pt[i].X;
}
if (destHeight < pt[i].Y)
{
destHeight = pt[i].Y;
}
}
destWidth++;
destHeight++;
destImg = new Bitmap(destWidth, destHeight);
destByte.LockBitmap(destImg, ImageLockMode.WriteOnly);
srcByte.LockBitmap(srcImg, ImageLockMode.ReadOnly);
calcWidth = srcByte.Width - 1;
calcHeight = srcByte.Height - 1;
// 頂点データは反時計回りだが、パラメータには時計回りでセットする
xa = pt[0].X; ya = pt[0].Y;
xb = pt[3].X; yb = pt[3].Y;
xc = pt[2].X; yc = pt[2].Y;
xd = pt[1].X; yd = pt[1].Y;
p.a = (xc - xd - xb + xa);
p.b = (xb - xa);
p.c = (xd - xa);
p.f = (yc - yd - yb + ya);
p.g = (yb - ya);
p.h = (yd - ya);
for (int y = 0; y < destHeight; y++)
{
for (int x = 0; x < destWidth; x++)
{
p.d = (x - xa);
p.e = (y - ya);
if (ResolveEqu(p, out s, out t) == false)
{
SetPixelByte(destByte, x, y, bgCol);
continue;
}
//if ((0 <= s && s <= 1.0) && (0 <= t && t <= 1.0))
//{
tx = s * calcWidth;
ty = t * calcHeight;
//}
if (Interpolate(srcByte, tx, ty, ref pxCol))
{
SetPixelByte(destByte, x, y, pxCol);
}
else
{
SetPixelByte(destByte, x, y, bgCol);
}
}
}
destByte.MarshalCopy();
}
catch (Exception ex)
{
return(false);
}
finally
{
try
{
if (srcByte != null)
{
srcByte.UnlockBitmap();
}
}
finally
{
if (destByte != null)
{
destByte.UnlockBitmap();
}
}
sw.Stop();
Console.WriteLine("Transform time: {0}", sw.ElapsedMilliseconds);
}
return(true);
}
