Re: post.trm image max colors patch

[Daniel J S. <dan...@ie...>]

Ethan Merritt wrote:
> On Thursday 09 February 2006 09:44 pm, Daniel J Sebald wrote:
> 
>>Attached is a bug fix for the PostScript image using the five operand
>>form (i.e., no palette).  The bug was that the max colors was not set
>>to 2^N, where N is 1, 2, 4, 8, or 12.  So if the gray scale max was
>>128 (2^7) the brightness was lower than it should have been.
> 
> 
> Could you please provide a demo script that shows the difference
> between before/after this patch?

Sure, from the demo directory:

set palette gray maxcolors 128
plot 'blutux.rgb' binary array=128x128 flipy format='%uchar%uchar%uchar' using ($1+$2+$3)/3 with image
set output
set term post monochrome eps
set output 'test.eps'
replot
set output
# To illustrate other terms work
set term png
set output 'test.png'
replot
set output

The EPS appears too dark without the patch when maxcolors is 2 4 16 256 or 4096.

Dan