imread/imwrite

[John W. Eaton]

On 19-Jun-2008, Thomas L. Scofield wrote:

| 
| If no one else is working on this, I would like to try my hand at  
| implementing these functions in Octave.
| 
| I've not contributed before, and I still haven't figured out  
| mercurial on my Intel Mac with OS 10.4.11.  So, I'll probably have  
| questions along the way concerning these.
| 
| I've followed discussions about imread/imwrite over the past 6 months  
| or so, so I am aware of things like
| 
|   - these functions are already implemented in the image package,  
| with special cases
|     implemented for .png and .jpg files.
|   - getting these functions into core Octave soon has been made a  
| priority by John Eaton.
|   - the general consensus has thus far been that the best compromise  
| between ease
|     of implementation and bloat is to employ the Magick++ library.

I think we should use the GraphicsMagick++ library since that seems to
have a stable interface.

| Is anyone else working on this?  Has anyone worked on it privately  
| and dropped it, but has useful information to share?

I only looked at it briefly without doing much actual work.  I think
the place to start is the code in Octave Forge.  To simplify the code
in Octave, I think I would would prefer to only use the
GraphicsMagick++ interface and drop the special cases.

| Dumb question from someone who hasn't used libraries for programming  
| in a long time: Does anyone ever remove chunks of code from a library  
| to produce a smaller library?  If it is even possible, does this  
| violate the GPL in any way?  My impression is that the beef against  
| Magick++ is that it has far more capability in it than is now needed,  
| causing a big draw on memory that isn't really necessary.

We won't be distributing the GraphicsMagick++ with Octave, so I would
not worry about this, at least for now.  Is the library really very
big?  It looks like it is around 2.7MB on my system, though it depends
on a lot of other libraries, some of which will be linked to Octave
anyway.  I don't know what the total size is, but does it matter that
much even if it is 20-30MB?

jwe