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DynaPDF Manual - Page 72

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Color spaces
Page 72 of 766
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.
 

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