public ResizeOperation(int?width, int?height, AnchorPositionMode anchor, ResizeMode mode)
{
_width = width;
_height = height;
_mode = mode;
_anchor = anchor;
}
/// <summary>
/// Resizes the image to a certain width and height. No resizing will be performed if
/// both width and height are set to <c>null</c>.
/// </summary>
/// <param name="width">The desired width. If set to <c>null</c> or <c>0</c>, the image will maintain it's original aspect ratio.</param>
/// <param name="height">The desired height. If set to <c>null</c> or <c>0</c>, the image will maintain it's original aspect ratio.</param>
/// <param name="anchor">The anchor position to use (if necessary).</param>
/// <param name="mode">The resize mode to use.</param>
/// <returns>The current module instance.</returns>
public MutateImage Resize(
int?width,
int?height,
AnchorPositionMode anchor = AnchorPositionMode.Center,
ResizeMode mode = ResizeMode.BoxPad)
{
_operations.Peek().Enqueue(new ResizeOperation(width, height, anchor, mode));
return(this);
}
/// <summary>
/// Draws a given image as an overlay on another image.
/// </summary>
/// <param name="baseImageFilename">Path to the base image.</param>
/// <param name="watermarkImageFilename">Path to the image to be drawn on the base image.</param>
/// <param name="anchorPos">Position to draw the watermark image at.</param>
/// <param name="paddingScale">How much padding to use in positioning.</param>
/// <param name="watermarkScale">How much to scale the watermark when drawn.</param>
/// <returns>The given base image with the watermark drawn on it.</returns>
public static Image WatermarkImage(string baseImageFilename,
string watermarkImageFilename,
AnchorPositionMode anchorPos = AnchorPositionMode.Bottom,
double paddingPercentageHorizontal = 0.10,
double paddingPercentageVertical = 0.1,
double watermarkScale = 0.2,
float opacity = 0.8f)
{
var baseImage = Image.Load(baseImageFilename);
using (var watermarkImage = Image.Load(watermarkImageFilename))
{
//resize the source image if it's too small to draw the watermark on
int resizeWidth = baseImage.Width;
int resizeHeight = baseImage.Height;
while (resizeWidth < watermarkImage.Width || resizeHeight < watermarkImage.Height)
{
resizeWidth *= 2;
resizeHeight *= 2;
}
baseImage.Mutate(x => x.Resize(resizeWidth, resizeHeight));
//scale the watermark so it's proportional in size to the source image
double scaleFactor = baseImage.Width / (double)watermarkImage.Width * watermarkScale;
watermarkImage.ResizeProportional(scaleFactor);
//compute padding
int paddingHorizontal = (int)(baseImage.Width * paddingPercentageHorizontal);
int paddingVertical = (int)(baseImage.Height * paddingPercentageVertical);
//compute the position to draw the watermark at (based on its top-left corner)
Point position;
switch (anchorPos)
{
case AnchorPositionMode.BottomRight:
position = new Point(baseImage.Width - watermarkImage.Width - paddingHorizontal, baseImage.Height - watermarkImage.Height - paddingVertical);
break;
case AnchorPositionMode.Bottom:
position = new Point(baseImage.Width / 2 - watermarkImage.Width / 2, baseImage.Height - watermarkImage.Height - paddingVertical);
break;
case AnchorPositionMode.BottomLeft:
position = new Point(paddingHorizontal, baseImage.Height - watermarkImage.Height - paddingVertical);
break;
default:
position = new Point(0, 0);
break;
}
//draw the watermark on the base image with 80% opacity (make this an argument?)
baseImage.Mutate(x => x.DrawImage(watermarkImage, position, opacity));
return(baseImage);
}
}
private static AnchorPositionMode GetAnchor(
ushort orientation,
CommandCollection commands,
CommandParser parser,
CultureInfo culture)
{
AnchorPositionMode anchor = parser.ParseValue <AnchorPositionMode>(commands.GetValueOrDefault(Anchor), culture);
return(ExifOrientationUtilities.Transform(anchor, orientation));
}
private static void Resize(Image <Rgba32> image, Size size, AnchorPositionMode anchorPositionModel)
{
image.Mutate(ctx => ctx.Resize(new ResizeOptions
{
Size = size,
Sampler = new Lanczos2Resampler(),
Mode = ResizeMode.Crop,
Position = anchorPositionModel
}));
}
public void Resize([DPR] int width, [DPR] int height, Utils.FilterTypes.ResizeMode mode, Utils.FilterTypes.AnchorPositionMode position)
{
ResizeMode mode2 = mode switch
{
Utils.FilterTypes.ResizeMode.Max => ResizeMode.Max,
Utils.FilterTypes.ResizeMode.Min => ResizeMode.Min,
Utils.FilterTypes.ResizeMode.Stretch => ResizeMode.Stretch,
Utils.FilterTypes.ResizeMode.Pad => ResizeMode.Pad,
Utils.FilterTypes.ResizeMode.Crop => ResizeMode.Crop,
_ => throw new Exception(),
};
AnchorPositionMode anchorPositionMode = position switch
{
Utils.FilterTypes.AnchorPositionMode.Bottom => AnchorPositionMode.Bottom,
Utils.FilterTypes.AnchorPositionMode.BottomLeft => AnchorPositionMode.BottomLeft,
Utils.FilterTypes.AnchorPositionMode.BottomRight => AnchorPositionMode.BottomRight,
Utils.FilterTypes.AnchorPositionMode.Center => AnchorPositionMode.Center,
Utils.FilterTypes.AnchorPositionMode.Left => AnchorPositionMode.Left,
Utils.FilterTypes.AnchorPositionMode.Right => AnchorPositionMode.Right,
Utils.FilterTypes.AnchorPositionMode.Top => AnchorPositionMode.Top,
Utils.FilterTypes.AnchorPositionMode.TopLeft => AnchorPositionMode.TopLeft,
Utils.FilterTypes.AnchorPositionMode.TopRight => AnchorPositionMode.TopRight,
_ => throw new Exception(),
};
//prevent upscaling
if (width > Context.Image.Width)
{
width = Context.Image.Width;
}
if (height > Context.Image.Height)
{
height = Context.Image.Height;
}
Context.Image.Mutate(m => m.Resize(new ResizeOptions()
{
Position = anchorPositionMode,
Mode = mode2,
Size = new Size(width, height)
}));
}
/// <summary>
/// Transforms the specified anchor value depending on the specified <paramref name="orientation" />.
/// </summary>
/// <param name="anchor">The input anchor value.</param>
/// <param name="orientation">The EXIF orientation.</param>
/// <returns>
/// The transformed anchor.
/// </returns>
public static AnchorPositionMode Transform(AnchorPositionMode anchor, ushort orientation)
/*
* New anchor position is determined by calculating the direction of the anchor relative to the source image.
* In the following example, the TopRight anchor becomes BottomRight
* T L
+-----------------------+ +--------------+
| *| | |
| | | |
| L | TL | R | |
| | | |
| | B | LB | T
| | | |
+-----------------------+ | |
| B | |
| |
| *|
+--------------+
| R
*/
=> orientation switch
{
public static IImageFilters Resize(this IImageFilters imageUrlBuilder, int width, int height, ResizeMode mode, AnchorPositionMode anchorPosition)
{
imageUrlBuilder.Filter($"resize({width},{height},{mode.ToUrlString()},{anchorPosition.ToUrlString()})");
return(imageUrlBuilder);
}