ImageGear22.Core Assembly > ImageGear.Processing Namespace > ImGearRasterProcessing Class > ConvertColorSpace Method : ConvertColorSpace(ImGearRasterPage,ImGearColorSpace,Boolean) Method |
'Declaration Public Overloads Shared Sub ConvertColorSpace( _ ByVal page As ImGearRasterPage, _ ByVal newColorSpace As ImGearColorSpace, _ ByVal doNotScalePixels As Boolean _ )
'Usage Dim page As ImGearRasterPage Dim newColorSpace As ImGearColorSpace Dim doNotScalePixels As Boolean ImGearRasterProcessing.ConvertColorSpace(page, newColorSpace, doNotScalePixels)
public static void ConvertColorSpace( ImGearRasterPage page, ImGearColorSpace newColorSpace, bool doNotScalePixels )
public: static void ConvertColorSpace( ImGearRasterPage* page, ImGearColorSpace newColorSpace, bool doNotScalePixels )
public: static void ConvertColorSpace( ImGearRasterPage^ page, ImGearColorSpace newColorSpace, bool doNotScalePixels )
This method Converts page to the newColorSpace
. This method works in two modes:
If dontScalePixels
is false (default), the image's pixels are recalculated.
If the new color space differs from the old color space only by an alpha channel (add, remove, set to pre-multiplied/non-pre-multiplied), ChannelDepths of color channels are preserved. For example, 5-6-5-8 RGBA will be converted to 5-6-5 RGB. Otherwise, ChannelDepths of color channels are set to maximum of original channel depths. For example, 3-5-4 RGB will be converted to 5-5-5-5 CMYK.
Any conversions are supported, except for conversion into Indexed color space.
The following formula is used to burn alpha (i.e., to convert from RGBA/P to RGB):
If Page is not pre-multiplied:
I = I * A + B (1-A)
If Page is pre-multiplied:
I = I + B (1-A)
If the image contains extra channels and newColorSpace contains extra channels, the method does not change them.
If dontScalePixels
is true, the page's color space property is changed, but the pixels are not modified. The number of channels of newColorSpace should be the same as that of the original image. When converting from Indexed to Grayscale, the palette is removed. When converting from Grayscale to Indexed, a default palette is created. Conversion to Grayscale colorspace takes into account the human eye's sensitivity to different parts of the light spectrum. ImageGear uses the following formula when converting from RGB to Grayscale: Gray = Red * 77 / 255 + Green * 151 / 255 + Blue * 28 / 255. If you need to convert an image to Grayscale using equal weights for Red, Green and Blue, or any other weights, use ConvertColorSpace(ImGearRasterPage,ImGearColorSpace,Double[,])