internal static Point GetSourceOrigin(Size imgSize, Size targetSize, TargetSpot targetSpot)
{
float x, y = 0;
switch (targetSpot)
{
case TargetSpot.Center: x = (imgSize.Width - targetSize.Width) / 2; y = (imgSize.Height - targetSize.Height) / 2; break;
case TargetSpot.TopMiddle: x = (imgSize.Width - targetSize.Width) / 2; y = 0; break;
case TargetSpot.BottomMiddle: x = (imgSize.Width - targetSize.Width) / 2; y = imgSize.Height - targetSize.Height; break;
case TargetSpot.MiddleRight: x = imgSize.Width - targetSize.Width; y = (imgSize.Height - targetSize.Height) / 2; break;
case TargetSpot.BottomRight: x = imgSize.Width - targetSize.Width; y = imgSize.Height - targetSize.Height; break;
case TargetSpot.TopRight: x = imgSize.Width - targetSize.Width; y = 0; break;
case TargetSpot.MiddleLeft: x = 0; y = (imgSize.Height - targetSize.Height) / 2; break;
case TargetSpot.BottomLeft: x = 0; y = imgSize.Height - targetSize.Height * 1; break;
case TargetSpot.TopLeft:
default: x = 0; y = 0; break;
}
return(new Point((int)x, (int)y));
}
/// <summary>
/// add image watermark over the uploaded image
/// </summary>
/// <param name="img"></param>
/// <param name="wmFileName"></param>
/// <param name="spot"></param>
/// <param name="stickToBorder"></param>
public static void ImageWatermark(this Image img, string wmFileName, TargetSpot spot = TargetSpot.TopRight, int margin = 10, int opacity = 35)
{
if (opacity > 0)
{
var graphics = Graphics.FromImage(img);
graphics.SmoothingMode = SmoothingMode.None;
graphics.CompositingMode = CompositingMode.SourceOver;
var wmImage = Image.FromFile(wmFileName);
if (opacity < 100)
{
wmImage = ImageOpacity.ChangeImageOpacity(wmImage, opacity);
}
var wmW = wmImage.Width;
var wmH = wmImage.Height;
var drawingPoint = ImageWatermarkPos(img.Width, img.Height, wmW, wmH, spot, margin);
graphics.DrawImage(wmImage, drawingPoint.X, drawingPoint.Y, wmW, wmH);
graphics.Dispose();
}
}
/// <summary>
/// watermark text pos
/// </summary>
/// <param name="imgWidth"></param>
/// <param name="imgHeight"></param>
/// <param name="fontSize"></param>
/// <param name="pos"></param>
/// <returns></returns>
private static Rectangle SetBGPos(int imgWidth, int imgHeight, int fontSize, TargetSpot spot, int margin)
{
Rectangle rect;
var bgHeight = fontSize * 2;
switch (spot)
{
case TargetSpot.TopLeft:
case TargetSpot.TopMiddle:
case TargetSpot.TopRight:
rect = new Rectangle(0, margin, imgWidth, bgHeight);
break;
case TargetSpot.MiddleLeft:
case TargetSpot.MiddleRight:
case TargetSpot.Center:
rect = new Rectangle(0, imgHeight / 2 - bgHeight / 2, imgWidth, bgHeight);
break;
case TargetSpot.BottomLeft:
case TargetSpot.BottomMiddle:
case TargetSpot.BottomRight:
default:
rect = new Rectangle(0, imgHeight - bgHeight - margin, imgWidth, bgHeight);
break;
}
return(rect);
}
/// <summary>
/// Crop an image according to the specified values
/// </summary>
/// <param name="imgSize">The source image size</param>
/// <param name="targetSize">The target image size</param>
/// <param name="targetSpot">The pre-defined spot of the source image to read and crop.
/// <see cref="TargetSpot"/></param>
public Crop(Size imgSize, Size targetSize, TargetSpot targetSpot)
{
TargetSize = targetSize;
SourceSize = targetSize;
SourceOrigin = ResizeMethods.SourceOrigin.GetSourceOrigin(imgSize, targetSize, targetSpot);
TargetOrigin = new Point(0, 0);
}
public Crop(Size imgSize, Size targetSize, TargetSpot targetSpot)
{
_targetSize = targetSize;
_sourceSize = targetSize;
_sourceOrigin = SourceOrigin.GetSourceOrigin(imgSize, targetSize, targetSpot);
_targetOrigin = new Point(0, 0);
}
/// <summary>
/// add watermark text over image
/// </summary>
/// <param name="img"></param>
/// <param name="text"></param>
/// <param name="color">hex8 Color e.g. #77FFFFFF</param>
/// <param name="bgColor">hex8 Color e.g. #00000000</param>
/// <param name="fontFamily"></param>
/// <param name="size"></param>
/// <param name="align"></param>
/// <param name="vAlign"></param>
/// <param name="style"></param>
public static void TextWatermark(this Image img,
string text,
string color = "#77FFFFFF", string bgColor = "#00000000",
string fontFamily = "Arial", int size = 24,
TargetSpot spot = TargetSpot.BottomLeft, FontStyle style = FontStyle.Regular, int margin = 10)
{
var graphics = Graphics.FromImage(img);
graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
graphics.TextContrast = 12;
graphics.SmoothingMode = SmoothingMode.None;
graphics.CompositingMode = CompositingMode.SourceOver;
var _bgAlpha = int.Parse(bgColor.Substring(1, 2), NumberStyles.HexNumber);
var _bgColor = bgColor.Substring(3, 6);
var bgBrush = new SolidBrush(
Color.FromArgb(_bgAlpha, ColorTranslator.FromHtml($"#{_bgColor}")));
var rectPos = SetBGPos(img.Width, img.Height, size, spot, margin);
graphics.FillRectangle(bgBrush, rectPos);
var textFont = new Font(fontFamily, size, style, GraphicsUnit.Pixel);
var _alpha = int.Parse(color.Substring(1, 2), NumberStyles.HexNumber);
var _color = color.Substring(3, 6);
var textBrush = new SolidBrush(
Color.FromArgb(_alpha, ColorTranslator.FromHtml($"#{_color}")));
var textMetrics = graphics.MeasureString(text, textFont);
var beforeText = SetTextAlign(textMetrics, img.Width, spot);
var drawPoint = new PointF(beforeText, rectPos.Y + (rectPos.Height / 4));
graphics.DrawString(text, textFont, textBrush, drawPoint);
graphics.Dispose();
}
internal static int SetTextAlign(SizeF textMetrics, int imgWidth, TargetSpot spot)
{
int space;
switch (spot)
{
case TargetSpot.BottomMiddle:
case TargetSpot.TopMiddle:
case TargetSpot.Center:
space = (int)(imgWidth - textMetrics.Width) / 2; break;
case TargetSpot.BottomRight:
case TargetSpot.MiddleRight:
case TargetSpot.TopRight:
space = (int)(imgWidth - textMetrics.Width) - 5; break;
case TargetSpot.BottomLeft:
case TargetSpot.MiddleLeft:
case TargetSpot.TopLeft:
default: space = 5; break;
}
return(space);
}
private static PointF ImageWatermarkPos(int imgWidth, int imgHeight, int wmWidth, int wmHeight, TargetSpot spot, int margin)
{
PointF point;
switch (spot)
{
case TargetSpot.BottomLeft: point = new PointF(margin, imgHeight - (wmHeight + margin)); break;
case TargetSpot.BottomMiddle: point = new PointF((imgWidth / 2) - (wmWidth / 2), imgHeight - (wmHeight + margin)); break;
case TargetSpot.BottomRight: point = new PointF(imgWidth - (wmWidth + margin), imgHeight - (wmHeight + margin)); break;
case TargetSpot.MiddleLeft: point = new PointF(margin, (imgHeight / 2) - (wmHeight / 2)); break;
case TargetSpot.Center: point = new PointF((imgWidth / 2) - (wmWidth / 2), (imgHeight / 2) - (wmHeight / 2)); break;
case TargetSpot.MiddleRight: point = new PointF(imgWidth - (wmWidth + margin), (imgHeight / 2) - (wmHeight / 2)); break;
case TargetSpot.TopLeft: point = new PointF(margin, margin); break;
case TargetSpot.TopMiddle: point = new PointF((imgWidth / 2) - (wmWidth / 2), margin); break;
case TargetSpot.TopRight:
default: point = new PointF(imgWidth - (margin + wmWidth), margin); break;
}
return(point);
}
/// <summary>
/// Directly crop original image without scaling it.
/// Final image aspect ratio is equal to given new width/height
/// </summary>
/// <param name="img"></param>
/// <param name="newWidth"></param>
/// <param name="newHeight"></param>
/// <param name="spot">target spot to crop and save</param>
/// <param name="ops">Graphic options <see cref="GraphicOptions"/></param>
/// <returns></returns>
public static Image Crop(this Image img, int newWidth, int newHeight, GraphicOptions ops, TargetSpot spot = TargetSpot.Center)
{
var resize = new Crop(img.Size, new Size(newWidth, newHeight), spot);
return(Resize(img, resize.SourceRect, resize.TargetRect, ops));
}
/// <summary>
/// Scale target image till shortest border are equal to target value,
/// then crop the additonal pixels from the longest border.
/// Final image aspect ratio is equal to the given new width/height
/// </summary>
/// <param name="img"></param>
/// <param name="newWidth"></param>
/// <param name="newHeight"></param>
/// <param name="spot"></param>
/// <returns></returns>
public static Image ScaleAndCrop(this Image img, int newWidth, int newHeight, TargetSpot spot = TargetSpot.Center)
{
var resize = new ScaleAndCrop(img.Size, new Size(newWidth, newHeight), spot);
return(Resize(img, resize.SourceRect, resize.TargetRect));
}
