[Digikam-users] Re: aspect ratio crop tool

[Remco Viëtor]

on Monday 16 May 2011, David Kerber wrote: 
> On 5/16/2011 11:42 AM, Dan McDaniel wrote:
> >
> > I have noticed that very often the Aspect Ratio Crop Tool does not crop
> > accurately, but will be off by pixel.  So, for example, if I want  a 5:4
> > aspect ratio which should be 1.25 the crop will be off by a pixel and
> > give a ratio of 1.2499 or such.
> >
> > This small difference does not affect the look of the image, but when I
> > send it to the photo service to be printed the software detects that it
> > is not in the correct ratio and each time I have to tell it that it's OK
> > to crop the image.
> >
> > Has anyone else noticed this? I'm using 1.2.0 on Debian and 1.9.0 on
> > Fedora and both exhibit this behavior.
> >
> 
> Are your originals' sizes such that 1.25 will give an exact pixel 
> result, and not have to be rounded either up or down to get to a whole 
> pixel?
> 

the size of the original isn't important, the size of the crop is:
if you take a length of 1003 pixels, there's no way you can get the 5:4 ratio 
exact on pixel level, as we only use whole pixels: you'd have to make the long 
edge either 1000 (giving 800 for the short side) or 1005 (804 for the short 
size). 

Already in 1.9.0 (and a few versions before iirc) there is the 'exact ratio' 
option, which indeed limits the sizes you can pick so that you get the exact 
ratio specified.

Remco