Re: [PanoTools-devel] Re:PTMender and Pano12.dll Updates

[Daniel M. G. <dmg...@uv...>]

 >> 1. Images created using cropped files (during the first stage, the
 >> actual creation of the panorama files) are not identical to the
 >> ones created using the non-cropped files. Look at the following
 >> file:
 >> 
 >> http://turingmachine.org/~dmg/temp/differenceCroppedTest.psd
 >> 
 >> This PSD file has 2 layers (the  uncropped is the background, the
 >> cropped is the first layer). The second layer is using difference
 >> blending. The result should be pure back. The third layer has
 >> exagerated contrast to show the difference. It is a subtle difference,
 >> but it is there.

 Max> Interesting.  Did you use the fast transform logic?  If so, that might explain 
 Max> the difference.  Its interpolation routines depend on start and end points that 

Indeed, that was the reason (I did not know hugin used fast-transform
by default). In fact the differences between fast transform and
default are way bigger than cropped vs non-cropped in fast transform.

 Max> could be different when dealing with cropped images versus full sized images.  
 Max> If not, then I'm not sure what might cause this.  In any case, the differences 
 Max> are so minor (and certainly visible to the naked eye), that I don't think it is 
 Max> much of an issue.

 >> 2. ComputingStitchingMasks is still memory hungry. I'll fix it in my
 >> next patch (ROWSPERSTRIP > 1). It is not using cropped files yet
 >> (if nobody else is looking into this I'll fix it).

 Max> Sounds good.

Ok, I'll do this in the following days. 

 >> 3. Photoshop is not able to read the cropped files properly. Is this a
 >> bug of a "feature" of the tiffs we are generating? If it can't then
 >> we need to add an option where they will be resized back to the
 >> entire size at the end.

 Max> Photoshop doesn't know about (as far as I'm aware) "cropped TIFFs".  Photoshop 
 Max> just reads the physical dimensions of the TIFF fils and ignores the offset 
 Max> data. Software has to be coded to read this offset data and deal with it 
 Max> intelligently.  Enblend does this, but Photoshop doesn't.

MMmm, this is bad news for 16 bit tiffs. Perhaps I'll implement a
"uncropper" tool that fixes this problem.


dmg


--
Daniel M. German                  "Science can be esoteric
    The Economist ->               technology has to be pragmatic"
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