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From: Christian Henning (chhenning_at_[hidden])
Date: 2007-04-23 11:37:41

Hi there, in the course of getting more familiar with gil 2.0 I
started writing a new extension for downsampling (don't if that's the
right term) an source image to its unsigned 8 bit counterpart. You
would use such an extension when trying to save an image that is using
more than 8 bit per channel, e.g. rgb32_image_t. Some file formats
only take unsigned 8bit per channel.

Attached there is the code I have so far. But there are still some
areas where my extension isn't generic enough or even the algorithm
fails due to my own short comings.

Here are some questions I have:

1. How do I figure out if the src channel type is signed? If it is I
would like to add half the value range to all channels and pixels.

2. When dealing with heterogeneous pixel types how can I initializes
them generically?

3. How do I compute the unsigned 8bit image type of the src image
type? I'm looking for xxx8_image_t.

Thanks ahead. Any ideas or suggestions are welcome.


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