/// <summary>
/// Adjusts brightness modifying lightness channel of Lab color space
/// </summary>
private static void AdjustLightnessLab()
{
using (var lChannel = new Bitmap())
using (var aChannel = new Bitmap())
using (var bChannel = new Bitmap())
{
using (var reader = ImageReader.Create("../../../../_Input/Chicago.jpg"))
using (var labConverter = new ColorConverter(PixelFormat.Format24bppLab))
using (var splitter = new LabChannelSplitter())
{
splitter.L = lChannel;
splitter.A = aChannel;
splitter.B = bChannel;
Pipeline.Run(reader + labConverter + splitter);
}
lChannel.ColorAdjustment.Brightness(brightnessAmount);
using (var combiner = new LabChannelCombiner())
using (var rgbConverter = new ColorConverter(PixelFormat.Format24bppRgb))
using (var writer = ImageWriter.Create("../../../../_Output/AdjustLightnessLab.jpg"))
{
combiner.L = lChannel;
combiner.A = aChannel;
combiner.B = bChannel;
rgbConverter.DestinationProfile = ColorProfile.FromSrgb();
Pipeline.Run(combiner + rgbConverter + writer);
}
}
}
/// <summary>
/// Tints using Lab color space
/// </summary>
private static void TintUsingLab(RgbColor color)
{
// You can hardcode a = 20, b = 60 for sepia effect
var labColor = RgbToLabColor(color);
var a = labColor.A;
var b = labColor.B;
using (var lChannel = new Bitmap())
{
// Convert to Lab color space and get lightness channel
using (var reader = ImageReader.Create("../../../../_Input/Chicago.jpg"))
using (var labConverter = new ColorConverter(PixelFormat.Format24bppLab))
using (var splitter = new LabChannelSplitter())
{
splitter.L = lChannel;
Pipeline.Run(reader + labConverter + splitter);
}
// Create a and b channels, combine with lightness channel and convert to RGB color space
using (var combiner = new LabChannelCombiner())
using (var aChannel = new Bitmap(lChannel.Width, lChannel.Height, PixelFormat.Format8bppGrayscale,
new GrayscaleColor((byte)(a + 127))))
using (var bChannel = new Bitmap(lChannel.Width, lChannel.Height, PixelFormat.Format8bppGrayscale,
new GrayscaleColor((byte)(b + 127))))
using (var rgbConverter = new ColorConverter(PixelFormat.Format24bppRgb))
using (var writer = ImageWriter.Create("../../../../_Output/TintUsingLab_" + color.ToString() + ".jpg"))
{
combiner.L = lChannel;
combiner.A = aChannel;
combiner.B = bChannel;
rgbConverter.DestinationProfile = ColorProfile.FromSrgb();
Pipeline.Run(combiner + rgbConverter + writer);
}
}
}
/// <summary>
/// Adjusts hue modifying [a] component of Lab color space
/// </summary>
private static void AdjustColorsUsingLab()
{
// L - lightness
// a - green/red
// b - blue/yellow
using (var lChannel = new Bitmap())
using (var aChannel = new Bitmap())
using (var bChannel = new Bitmap())
{
using (var reader = ImageReader.Create("../../../../_Input/Chicago.jpg"))
using (var labConverter = new ColorConverter(PixelFormat.Format24bppLab))
using (var splitter = new LabChannelSplitter())
{
splitter.L = lChannel;
splitter.A = aChannel;
splitter.B = bChannel;
Pipeline.Run(reader + labConverter + splitter);
}
// Increase yellow
bChannel.ColorAdjustment.ChannelBalance(new float[] { 0.1f }, new float[] { 1f });
using (var combiner = new LabChannelCombiner())
using (var rgbConverter = new ColorConverter(PixelFormat.Format24bppRgb))
using (var writer = ImageWriter.Create("../../../../_Output/AdjustColorsUsingLab.jpg"))
{
combiner.L = lChannel;
combiner.A = aChannel;
combiner.B = bChannel;
rgbConverter.DestinationProfile = ColorProfile.FromSrgb();
Pipeline.Run(combiner + rgbConverter + writer);
}
}
}
/// <summary>
/// Corrects tone modifying lightness component of Lab color space
/// </summary>
private static void AdjustLevelsUsingLab()
{
// L - lightness
// a - green/red
// b - blue/yellow
using (var lChannel = new Bitmap())
using (var aChannel = new Bitmap())
using (var bChannel = new Bitmap())
{
using (var reader = ImageReader.Create("../../../../_Input/Chicago.jpg"))
using (var labConverter = new ColorConverter(PixelFormat.Format24bppLab))
using (var splitter = new LabChannelSplitter())
{
splitter.L = lChannel;
splitter.A = aChannel;
splitter.B = bChannel;
Pipeline.Run(reader + labConverter + splitter);
}
lChannel.ColorAdjustment.Levels(0.03F, 0.9F, 0.05F, 1.5F, 0.7F, HistogramMode.Sum);
using (var combiner = new LabChannelCombiner())
using (var rgbConverter = new ColorConverter(PixelFormat.Format24bppRgb))
using (var writer = ImageWriter.Create("../../../../_Output/AdjustLevelsUsingLab.jpg"))
{
combiner.L = lChannel;
combiner.A = aChannel;
combiner.B = bChannel;
rgbConverter.DestinationProfile = ColorProfile.FromSrgb();
Pipeline.Run(combiner + rgbConverter + writer);
}
}
}