DynaPDF Manual - Page 100
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Color spaces
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Active color space
Description
CalGray
The color space can be set to 1 channel images without a color table. The image data
should be defined in a color depth of 1 or 8 bits per pixel. Color depths of 2 or 4 bits
are unusual and maybe not supported in all versions of Adobe's Acrobat or on the
output device. Consider the special treatment of 1 bit images.
CalRGB
The image color space can be any 3 channel color space with exception of Lab.
ICCBased
The image color space and the input color space of the corresponding ICC profile
must be compatible.
Indexed
The color space can be set to 1 channel images with or without a color table. An
already existing color table in the image file will be replaced. Consider the special
treatment of 1 bit images.
Separation
The color space can be set to 1 channel images without a color table. The image data
should be defined in a color depth of 1 or 8 bits per pixel. Color depths of 2 or 4 bits
are unusual and maybe not supported in all versions of Adobe's Acrobat or on the
output device. 1 channel images without a color table are normally defined in
DeviceGray or CalGray but these color spaces are additive color spaces while
Separation is a subtractive color space. To get an image in a compatible range
DynaPDF inverts the pixel data. This behaviour must be taken into account when
creating images for a Separation color space. Consider also the special treatment of
1 bit images.
DeviceN
The supported bit depths and image color spaces depend on the number of color
components defined in the DeviceN color space and which function is used to insert
the image. The default function to insert images defined in a DevicN color space is
InsertRawImage(). This function supports images with up to 32 color channels.
However, it is also possible to exchange the color space of arbitrary images with a
DeviceN color space. The following sub clauses describe the handling if the image is
loaded from an arbitrary image file with InsertImage(), InsertImageEx(), or
InsertImageFromBuffer().
Images with less than 4 color channels will be inverted because DeviceN is a
subtractive color space and images with less than 4 color components are defined in
an additive color space in normal image files.
Num Comp. Supported image formats
1
The image can be any 1 channel image without a color table.
However, the image data should be defined in a color depth of 1 or
8 bits per pixel. Color depths of 2 or 4 bits are unusual and maybe
not supported in all versions of Adobe's Acrobat or on the output
device.
2
DeviceN color spaces with 2 color components can be used with 1
bit images without a color table.
Previous topic: Color Spaces and Images, Handling of non-device color spaces
Next topic: Special treatment of 1 bit images, How to preserve the image color space?, Image Resolution