Resize algorithm in JPG exports : bicubic?

[gaminos]

Hi,

my JPG exports in Aftershot are quite blurred/fuzzy.

By comparison with Photoshop resize algorithm, it appears Aftershot uses some kind of mixed bicubic/bicubic sharper algorithm.

PSD, bicubic smoother :


PSD, bicubic :


ASP :


PSD, bicubic sharper :


PSD, bilinear :



Bilinear is best for micro details, here is a comparison between a PSD bilinear USM 50/0.3/0 versus a ASP USM 50/0.3/0 (look at grass on foreground) :





Is there any way to choose some bilinear export, as I think it's the best export for web.

[afx]

There is no way to change the algorithm.
And I personally think Bicubic is not really good.
Lanczos would be miles better.

I know guys who use an Imagemagick backend in the batch queue for resizing. It defaults to Ianczos.

cheers
afx

[gaminos]

Hey, thanks for your quick reply.

What do you mean by batch queue?

[Hobgoblin]

There is no way to change the algorithm.
And I personally think Bicubic is not really good.
Lanczos would be miles better.

I know guys who use an Imagemagick backend in the batch queue for resizing. It defaults to Ianczos.

cheers
afx

Nconvert will do this for you too.
I forget who posted this originally. But basically modify your output batch to call nconvert with this command line.

Code: Select all

-o $%_res -out jpeg -D -q 93 -dct 2 -opthuff -subsampling 2 -resize 1800 1800 -ratio -rflag orient -rtype lanczos -keep_icc %1

AFX may know where the original post came from?
Nconvert is cross platform and available from http://www.xnview.com/en/nconvert/

R.

[gaminos]

Wow, I'm really impressed with this feature.
Flexible and powerful associated with ImageMagick !

Glad to discover it, now ASP is my perfect tool.

I used these parameters with mogrify / image magick :

-resize 950 -unsharp 0x1+0.05+0.03 -quality 81 %1

[gaminos]

To go further, in order to avoid cmd windows opening on each image process :

download hstart : http://www.ntwind.com/software/hstart.html
unzip it
in ASP : select hstart as main program.

Add this kind of command :


Then, on ASP export with imagemagick, no more command window!