Re: [Matplotlib-users] Problem with .png files?

[Michael Droettboom]

Unfortunately, I'm not able to reproduce this here with the .py you 
attached.  Both SVN r3926 (before the PNG resolution change) and SVN 
r3927 (after the PNG resolution change) work for me.  Are you comparing 
those two SVN revisions, or SVN vs. 0.90.1?

I can confirm that the PNG you attached is all white and fully transparent.

Just for information, my machine (RHEL4) has libpng 1.2.7.

Can you send a copy of your matplotlibrc?  Also, can you save out a .raw 
image?  (If you rename it to foo.rgba, you can display these images with 
the ImageMagick command "display -size 1800x1200 -depth 8 foo.rgba") 
That would help determine whether the problem is in the PNG-writing code 
or something higher up.

Cheers,
Mike

Wayne E. Harlan wrote:
> Michael:
> 
> I tried a complete checkout for comparison (3929).  In the meantime, my 
> libpng is 1.2.18 (installed from source as is everything - this is an 
> LFS/BLFS system.)  Yes, the plot was working before the change and I can 
> send you some png's from that if you need to see them, or I can 
> backtrack to 0.90.1 and repeat this.  Please bear in mind that the plot 
> displays (and always has) quite correctly on screen - it's just the 
> saved file that consists of just background.  I have attached the 
> script, the resulting png and a saved screenshot from the Gimp.  
> Attachments are gzipped.
> 
> Wayne
> 
> Michael Droettboom wrote:
>> Hmmm.  I'm very surprised that this change could cause that.  All it 
>> does is add an additional metadata chunk to the PNG file, which 
>> shouldn't have any affect on the image data itself.  simple_plot.py 
>> works fine for me in GIMP 2.0.5 both before and after this change.  
>> Can you verify that this plot was working before the change to save 
>> the resolution in the PNG file?  If so, can you send me the source for 
>> your plot and the PNG file?  Also, what version of libpng are you 
>> using? (pkg-config --version libpng should display this on most recent 
>> Linux distros).
>>   

-- 
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/
_______________________________________________
Matplotlib-users mailing list
Matplotlib-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-users