[magick-users] Saving using magickcore

[Christopher Garrett]

Thank you very much.  I think I will try the changes you suggest in magickcore
first, and then experiment with Magickwand since it does look better suited to
my needs.  The API is quite big at first glance, but looks a lot friendlier to
use!  Is it built upon magickcore, or is it completely standalone? 

Regarding magickwand usage, I see that I can create a new image with
MagickNewImage() as a start.  Is there a way to specify that it should be stored
on disk only, or to stream pixels, rows or tiles from my image data to the file
on disk in order to control memory usage when saving large images?  Is there a
recommended strategy for this when using imagemagick? (my image data is held in
tiles internally, but it is easy for me to pull out entire rows or single
pixels). 

Finally, is there a tutorial anyone can recommend to me for either magickwand,
or magickcore usage (preferably for the C api obviously)?  I have been unable to
find one as yet. 

Best regards, 

Chris.  


Chris Garrett
UNIX Administrator
MISD Operations Group, University of Cambridge 
01223-(7)66687

-----Original Message-----
From: omicronpersei8 at imagemagick.org [mailto:omicronpersei8 at imagemagick.org] 
Sent: 26 April 2007 20:08
To: Christopher Garrett; magick-users at imagemagick.org
Subject: Re: [magick-users] Saving using magickcore

> does not actually produce a file at the end of it

We see a few mistakes.  Number 1, user MagickWand rather than MagickCore.
If you must use MagickCore,  you need to set the output image filename at
image->filename.  You also need to call SyncImagePixels() at the close of your
outer loop to ensure your pixels are updated.  Finally, your image assumes a Q8
version of ImageMagick.  If you have a Q16 version you will need to scale your
pixels froom 0..255 to 0..65535.