Imagedata row order

[Jeanne A. E. DeVoto]

At 12:32 PM -0600 7/25/2006, Dar Scott wrote:
>>No. It's run-length-encoded. Just as well, since the text property 
>>is what's stored on disk, and a 32-bit image with no compression 
>>whatever would take up a ton of room. Take a look at the length of 
>>the text versus the length of the imageData of a typical image 
>>object.
>
>Wow, where is this in the dictionary?

I don't think it is ;-), except in a passing mention (RLE is expanded 
in the glossary).

Not that it would be a bad idea to document the internal format 
necessarily, but I don't think anyone ever thought in terms of people 
wanting to modify the text of an image on the fly - since you'd 
generally export it or use a referenced image, and do the 
modifications in an image editing program. (This was before anyone I 
know of had started thinking of doing image processing tasks in Rev.)

>I have tried setting the text of an image to some PBM/PGM/PPM 
>formats (P6 and P3 mostly, I think), but got no response to the 
>image or size.  When I tried to subsequently export, I got an error.
>
>Maybe something was wrong with my data.

Could be. I have successfully imported PBM and PGM files created by 
Graphic Converter, for what's it's worth. I don't think you can 
create a PBM/PPM/PGM by setting an image's text property - it looks 
like it's getting converted to PNG or RLE on the way in when it's 
imported, so there may not actually be such a thing as "a Rev image 
object in PBM/PGM/PPM format".
-- 
jeanne a. e. devoto ~ revolution at jaedworks.com
http://www.jaedworks.com