-map shuffles colormap
Posted: 2007-08-08T16:27:05-07:00
Posted this in the Users section. Got no reply to it, it probably isn't a feature - is it a bug?
Hi all,
I am struggling with the following. I have two Windows BMP files, both 4-bit indexed using the "standard" windows colormap. I have to combine both (compose), but if I do this without further action the resulting file is a 24bit DirectClass BMP. I need this BMP to use exactly the same colormap as the original images, so I used -map. This applies the colormap, BUT shuffles the colors. I was a bit surprised by this, although I can see some reason for it: the set of colors is equal to the original map, so why bother with the order.
Well... in this case the image must be fed by some kind of hardware (PLC) that is programmed to act on index numbers (and not read the associated colors). So it want index 11 for yellow, 9 for red and 0 for black. Is there any way I can accomplish this? The "sad" thing is that the colormap remains intact throughout the complete process: although the image changes to DirectClass the colormap stays unchanged (but obviously it is not used). As soon as I use the -map action the colormap changes.
Hope someone can help me here. I'll attach some colormap info below. Please note: if there is a way to revert the image back to PseudoColor without applying a map and without the image being optimized, that is a solution too...
Kind regards,
Frank
===
Reading 3 files: a unique pixel file and the two images involved in the composition (first will be destination)
After the composition the list is the same, but as soon as I apply the colormap of the first image (unique pixel) this happens:
Hi all,
I am struggling with the following. I have two Windows BMP files, both 4-bit indexed using the "standard" windows colormap. I have to combine both (compose), but if I do this without further action the resulting file is a 24bit DirectClass BMP. I need this BMP to use exactly the same colormap as the original images, so I used -map. This applies the colormap, BUT shuffles the colors. I was a bit surprised by this, although I can see some reason for it: the set of colors is equal to the original map, so why bother with the order.
Well... in this case the image must be fed by some kind of hardware (PLC) that is programmed to act on index numbers (and not read the associated colors). So it want index 11 for yellow, 9 for red and 0 for black. Is there any way I can accomplish this? The "sad" thing is that the colormap remains intact throughout the complete process: although the image changes to DirectClass the colormap stays unchanged (but obviously it is not used). As soon as I use the -map action the colormap changes.
Hope someone can help me here. I'll attach some colormap info below. Please note: if there is a way to revert the image back to PseudoColor without applying a map and without the image being optimized, that is a solution too...
Kind regards,
Frank
===
Reading 3 files: a unique pixel file and the two images involved in the composition (first will be destination)
Code: Select all
0 : 0,0,0,0 0,0,0,0 0,0,0,0
1 : 32896,0,0,0 32896,0,0,0 32896,0,0,0
2 : 0,32896,0,0 0,32896,0,0 0,32896,0,0
3 : 32896,32896,0,0 32896,32896,0,0 32896,32896,0,0
4 : 0,0,32896,0 0,0,32896,0 0,0,32896,0
5 : 32896,0,32896,0 32896,0,32896,0 32896,0,32896,0
6 : 0,32896,32896,0 0,32896,32896,0 0,32896,32896,0
7 : 32896,32896,328 32896,32896,328 32896,32896,328
8 : 49344,49344,493 49344,49344,493 49344,49344,493
9 : 65535,0,0,0 65535,0,0,0 65535,0,0,0
10: 0,65535,0,0 0,65535,0,0 0,65535,0,0
11: 65535,65535,0,0 65535,65535,0,0 65535,65535,0,0
12: 0,0,65535,0 0,0,65535,0 0,0,65535,0
13: 65535,0,65535,0 65535,0,65535,0 65535,0,65535,0
14: 0,65535,65535,0 0,65535,65535,0 0,65535,65535,0
15: 65535,65535,655 65535,65535,655 65535,65535,655Code: Select all
0 : 0,0,0,0 0,0,0,0 0,0,0,0
1 : 32896,0,0,0 32896,0,0,0 32896,0,0,0
2 : 0,32896,0,0 65535,0,0,0 0,32896,0,0
3 : 32896,32896,0,0 0,32896,0,0 32896,32896,0,0
4 : 0,0,32896,0 0,65535,0,0 0,0,32896,0
5 : 32896,0,32896,0 32896,32896,0,0 32896,0,32896,0
6 : 0,32896,32896,0 65535,65535,0,0 0,32896,32896,0
7 : 32896,32896,328 0,0,32896,0 32896,32896,328
8 : 49344,49344,493 0,0,65535,0 49344,49344,493
9 : 65535,0,0,0 32896,0,32896,0 65535,0,0,0
10: 0,65535,0,0 65535,0,65535,0 0,65535,0,0
11: 65535,65535,0,0 0,32896,32896,0 65535,65535,0,0
12: 0,0,65535,0 0,65535,65535,0 0,0,65535,0
13: 65535,0,65535,0 32896,32896,328 65535,0,65535,0
14: 0,65535,65535,0 49344,49344,493 0,65535,65535,0
15: 65535,65535,655 65535,65535,655 65535,65535,655