public static byte[] ImageScalingToRange(string path, int maxWidth, int maxHeight, int quality)
{
byte[] bytes = null;
if (!System.IO.File.Exists(path))
{
return(bytes);
}
var fileStream = new System.IO.FileStream(path, System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read); //fileInfo.OpenRead();
if (fileStream.Length > maxLength)
{
fileStream.Dispose();
return(bytes);
}
var sKManagedStream = new SkiaSharp.SKManagedStream(fileStream, true);
var sKBitmap = SkiaSharp.SKBitmap.Decode(sKManagedStream);
sKManagedStream.Dispose();
if (sKBitmap.IsEmpty)
{
return(bytes);
}
if (maxWidth < 1)
{
maxWidth = 1;
}
if (maxHeight < 1)
{
maxHeight = 1;
}
if (quality < 1)
{
quality = 1;
}
if (quality > 100)
{
quality = 100;
}
int oW = sKBitmap.Width;
int oH = sKBitmap.Height;
int nW = oW;
int nH = oH;
if (nW < maxWidth && nH < maxHeight)//放大
{
if (nW < maxWidth)
{
var r = (double)maxWidth / (double)nW;
nW = maxWidth;
nH = (int)Math.Floor((double)nH * r);
}
if (nH < maxHeight)
{
var r = (double)maxHeight / (double)nH;
nH = maxHeight;
nW = (int)Math.Floor((double)nW * r);
}
}
//限制超出(缩小)
if (nW > maxWidth)
{
var r = (double)maxWidth / (double)nW;
nW = maxWidth;
nH = (int)Math.Floor((double)nH * r);
}
if (nH > maxHeight)
{
var r = (double)maxHeight / (double)nH;
nH = maxHeight;
nW = (int)Math.Floor((double)nW * r);
}
var sKBitmap2 = new SkiaSharp.SKBitmap(nW, nH);
var sKCanvas = new SkiaSharp.SKCanvas(sKBitmap2);
var sKPaint = new SkiaSharp.SKPaint
{
FilterQuality = SkiaSharp.SKFilterQuality.Medium,
IsAntialias = true
};
sKCanvas.DrawBitmap(
sKBitmap,
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = 0, Y = 0
},
Size = new SkiaSharp.SKSize {
Height = oH, Width = oW
}
},
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = 0, Y = 0
},
Size = new SkiaSharp.SKSize {
Height = nH, Width = nW
}
}, sKPaint);
sKCanvas.Dispose();
var sKImage2 = SkiaSharp.SKImage.FromBitmap(sKBitmap2);
sKBitmap2.Dispose();
var data = sKImage2.Encode(GetImageFormatByPath(path), quality);
sKImage2.Dispose();
bytes = data.ToArray();
data.Dispose();
return(bytes);
}
/// <summary>
/// 生成二维码(320*320)
/// </summary>
/// <param name="text">文本内容</param>
/// <param name="format">保存格式</param>
/// <param name="logoImgae">Logo图片(缩放到真实二维码区域尺寸的1/6)</param>
/// <param name="keepWhiteBorderPixelVal">白边处理(负值表示不做处理，最大值不超过真实二维码区域的1/10)</param>
/// <returns></returns>
public static byte[] QRCoder(string text, SkiaSharp.SKEncodedImageFormat format, byte[] logoImgae = null, int keepWhiteBorderPixelVal = -1)
{
byte[] reval = null;
int width = 320;
int height = 320;
var qRCodeWriter = new ZXing.QrCode.QRCodeWriter();
var hints = new Dictionary <ZXing.EncodeHintType, object>();
hints.Add(ZXing.EncodeHintType.CHARACTER_SET, "utf-8");
hints.Add(ZXing.EncodeHintType.QR_VERSION, 8);
hints.Add(ZXing.EncodeHintType.ERROR_CORRECTION, ZXing.QrCode.Internal.ErrorCorrectionLevel.Q);
var bitMatrix = qRCodeWriter.encode(text, ZXing.BarcodeFormat.QR_CODE, width, height, hints);
var w = bitMatrix.Width;
var h = bitMatrix.Height;
var sKBitmap = new SkiaSharp.SKBitmap(w, h);
int blackStartPointX = 0;
int blackStartPointY = 0;
int blackEndPointX = w;
int blackEndPointY = h;
#region --绘制二维码(同时获取真实的二维码区域起绘点和结束点的坐标)--
var sKCanvas = new SkiaSharp.SKCanvas(sKBitmap);
var sKColorBlack = SkiaSharp.SKColor.Parse("000000");
var sKColorWihte = SkiaSharp.SKColor.Parse("ffffff");
sKCanvas.Clear(sKColorWihte);
bool blackStartPointIsNotWriteDown = true;
for (var y = 0; y < h; y++)
{
for (var x = 0; x < w; x++)
{
var flag = bitMatrix[x, y];
if (flag)
{
if (blackStartPointIsNotWriteDown)
{
blackStartPointX = x;
blackStartPointY = y;
blackStartPointIsNotWriteDown = false;
}
blackEndPointX = x;
blackEndPointY = y;
sKCanvas.DrawPoint(x, y, sKColorBlack);
}
else
{
//sKCanvas.DrawPoint(x, y, sKColorWihte);//不用绘制(背景是白色的)
}
}
}
sKCanvas.Dispose();
#endregion
int qrcodeRealWidth = blackEndPointX - blackStartPointX;
int qrcodeRealHeight = blackEndPointY - blackStartPointY;
#region -- 处理白边 --
if (keepWhiteBorderPixelVal > -1)//指定了边框宽度
{
var borderMaxWidth = (int)Math.Floor((double)qrcodeRealWidth / 10);
if (keepWhiteBorderPixelVal > borderMaxWidth)
{
keepWhiteBorderPixelVal = borderMaxWidth;
}
var nQrcodeRealWidth = width - keepWhiteBorderPixelVal - keepWhiteBorderPixelVal;
var nQrcodeRealHeight = height - keepWhiteBorderPixelVal - keepWhiteBorderPixelVal;
var sKBitmap2 = new SkiaSharp.SKBitmap(width, height);
var sKCanvas2 = new SkiaSharp.SKCanvas(sKBitmap2);
sKCanvas2.Clear(sKColorWihte);
//二维码绘制到临时画布上时无需抗锯齿等处理(避免文件增大)
sKCanvas2.DrawBitmap(
sKBitmap,
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = blackStartPointX, Y = blackStartPointY
},
Size = new SkiaSharp.SKSize {
Height = qrcodeRealHeight, Width = qrcodeRealWidth
}
},
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = keepWhiteBorderPixelVal, Y = keepWhiteBorderPixelVal
},
Size = new SkiaSharp.SKSize {
Width = nQrcodeRealWidth, Height = nQrcodeRealHeight
}
});
blackStartPointX = keepWhiteBorderPixelVal;
blackStartPointY = keepWhiteBorderPixelVal;
qrcodeRealWidth = nQrcodeRealWidth;
qrcodeRealHeight = nQrcodeRealHeight;
sKCanvas2.Dispose();
sKBitmap.Dispose();
sKBitmap = sKBitmap2;
}
#endregion
#region -- 绘制LOGO --
if (logoImgae != null && logoImgae.Length > 0)
{
SkiaSharp.SKBitmap sKBitmapLogo = SkiaSharp.SKBitmap.Decode(logoImgae);
if (!sKBitmapLogo.IsEmpty)
{
var sKPaint2 = new SkiaSharp.SKPaint
{
FilterQuality = SkiaSharp.SKFilterQuality.None,
IsAntialias = true
};
var logoTargetMaxWidth = (int)Math.Floor((double)qrcodeRealWidth / 6);
var logoTargetMaxHeight = (int)Math.Floor((double)qrcodeRealHeight / 6);
var qrcodeCenterX = (int)Math.Floor((double)qrcodeRealWidth / 2);
var qrcodeCenterY = (int)Math.Floor((double)qrcodeRealHeight / 2);
var logoResultWidth = sKBitmapLogo.Width;
var logoResultHeight = sKBitmapLogo.Height;
if (logoResultWidth > logoTargetMaxWidth)
{
var r = (double)logoTargetMaxWidth / logoResultWidth;
logoResultWidth = logoTargetMaxWidth;
logoResultHeight = (int)Math.Floor(logoResultHeight * r);
}
if (logoResultHeight > logoTargetMaxHeight)
{
var r = (double)logoTargetMaxHeight / logoResultHeight;
logoResultHeight = logoTargetMaxHeight;
logoResultWidth = (int)Math.Floor(logoResultWidth * r);
}
var pointX = qrcodeCenterX - (int)Math.Floor((double)logoResultWidth / 2) + blackStartPointX;
var pointY = qrcodeCenterY - (int)Math.Floor((double)logoResultHeight / 2) + blackStartPointY;
var sKCanvas3 = new SkiaSharp.SKCanvas(sKBitmap);
var sKPaint = new SkiaSharp.SKPaint
{
FilterQuality = SkiaSharp.SKFilterQuality.Medium,
IsAntialias = true
};
sKCanvas3.DrawBitmap(
sKBitmapLogo,
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = 0, Y = 0
},
Size = new SkiaSharp.SKSize {
Height = sKBitmapLogo.Height, Width = sKBitmapLogo.Width
}
},
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = pointX, Y = pointY
},
Size = new SkiaSharp.SKSize {
Height = logoResultHeight, Width = logoResultWidth
}
}, sKPaint);
sKCanvas3.Dispose();
sKPaint.Dispose();
sKBitmapLogo.Dispose();
}
else
{
sKBitmapLogo.Dispose();
}
}
#endregion
SkiaSharp.SKImage sKImage = SkiaSharp.SKImage.FromBitmap(sKBitmap);
sKBitmap.Dispose();
var data = sKImage.Encode(format, 75);
sKImage.Dispose();
reval = data.ToArray();
data.Dispose();
return(reval);
}
public static byte[] ImageMaxCutByCenter(string path, int saveWidth, int saveHeight, int quality)
{
byte[] bytes = null;
if (!System.IO.File.Exists(path))
{
return(bytes);
}
var fileStream = new System.IO.FileStream(path, System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read); //fileInfo.OpenRead();
if (fileStream.Length > maxLength)
{
fileStream.Dispose();
return(bytes);
}
var sKManagedStream = new SkiaSharp.SKManagedStream(fileStream, true);
var sKBitmap = SkiaSharp.SKBitmap.Decode(sKManagedStream);
sKManagedStream.Dispose();
if (sKBitmap.IsEmpty)
{
return(bytes);
}
if (saveWidth < 1)
{
saveWidth = 1;
}
if (saveHeight < 1)
{
saveHeight = 1;
}
if (quality < 1)
{
quality = 1;
}
if (quality > 100)
{
quality = 100;
}
int oW = sKBitmap.Width;
int oH = sKBitmap.Height;
int cutW = saveWidth;
int cutH = saveHeight;
double ratio = 1;
if (cutW > oW)
{
ratio = (double)oW / (double)cutW;
cutH = Convert.ToInt32((double)cutH * ratio);
cutW = oW;
if (cutH > oH)
{
ratio = (double)oH / (double)cutH;
cutW = Convert.ToInt32((double)cutW * ratio);
cutH = oH;
}
}
else if (cutW < oW)
{
ratio = (double)oW / (double)cutW;
cutH = Convert.ToInt32(Convert.ToDouble(cutH) * ratio);
cutW = oW;
if (cutH > oH)
{
ratio = (double)oH / (double)cutH;
cutW = Convert.ToInt32((double)cutW * ratio);
cutH = oH;
}
}
else
{
if (cutH > oH)
{
ratio = (double)oH / (double)cutH;
cutW = Convert.ToInt32((double)cutW * ratio);
cutH = oH;
}
}
int startX = oW > cutW ? (oW / 2 - cutW / 2) : (cutW / 2 - oW / 2);
int startY = oH > cutH ? (oH / 2 - cutH / 2) : (cutH / 2 - oH / 2);
var sKBitmap2 = new SkiaSharp.SKBitmap(saveWidth, saveHeight);
var sKCanvas = new SkiaSharp.SKCanvas(sKBitmap2);
var sKPaint = new SkiaSharp.SKPaint
{
FilterQuality = SkiaSharp.SKFilterQuality.Medium,
IsAntialias = true
};
sKCanvas.DrawBitmap(
sKBitmap,
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = startX, Y = startY
},
Size = new SkiaSharp.SKSize {
Height = cutH, Width = cutW
}
},
new SkiaSharp.SKRect
{
Location = new SkiaSharp.SKPoint {
X = 0, Y = 0
},
Size = new SkiaSharp.SKSize {
Height = saveHeight, Width = saveWidth
}
}, sKPaint);
sKCanvas.Dispose();
var sKImage2 = SkiaSharp.SKImage.FromBitmap(sKBitmap2);
sKBitmap2.Dispose();
var data = sKImage2.Encode(GetImageFormatByPath(path), quality);
sKImage2.Dispose();
bytes = data.ToArray();
data.Dispose();
return(bytes);
}