Append+ function on indexed images

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mattyrb
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Joined: 2018-10-03T08:08:10-07:00
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Append+ function on indexed images

Post by mattyrb »

Hi,
I have two indexed colour images (16 colours). I'd appended them together and was hoping that the palettes would be stacked one after the other but Imagemagick seems to optimise the palette? I notice in most cases the 16th colour is moved to the 2nd colour (index position 1) and the rest of the palette is left untouched. Could someone tell me what rules are being applied to optimise the palette?

Best wishes,
Matt

snibgo
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Location: England, UK

Re: Append+ function on indexed images

Post by snibgo »

IM doesn't guarantee to do anything in particular with palettes. You could examine the source code to see what it happens to do currently and how it orders the entries, but that could change in future versions.

IM doesn't provide control of palettes for users. Gimp does.
snibgo's IM pages: im.snibgo.com

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