Legacy ImageMagick Discussions Archive

Testing on IM 6.6.3-0 Q16 (non-hdri) on my Mac OSX Tiger.

All these work fine for a round trip. NOTE: that if the intermediate image does not support multi-frame images, you will get two images, a -0 and a -1 version, from the -fft and so need to specify both as input to -ift. PNG does not support multi-frame images but MIFF does.


lena2.png -fft -ift lena2_fftift.png

convert lena2.png -fft lena2_fft.png
convert lena2_fft-0.png lena2_fft-1.png -ift lena2_fft_png_ift.png

convert lena2.png -fft lena2_fft.miff
convert lena2_fft.miff -ift lena2_fft_miff_ift.png


Be sure that FFTW delegate is properly installed. Check by typing:

convert -list configure

Look at the line starting with DELEGATES. It should include fftw. If it does not then you have not installed it correctly or need to reinstall IM AFTER installing FFTW.

I am not a windows user, so don't know the details of getting fftw to work with IM. See this link for possible help. viewtopic.php?f=4&t=14251#p56836

Hope this helps.

If you are running HDRI, then let me know and I will reinstall IM in HDRI mode and test again.

Fred

I was gathering the info when your second post arrived - thanks.

I think the command pipeline should be ok:
C:\>convert ndt.png -fft ndt_fft.png
C:\>convert ndt_fft-0.png ndt_fft-1.png -ift ndt_roundtrip2.png

C:\>compare -metric rmse ndt.png ndt_roundtrip2.png NULL.
390.278 (0.00595527)
(Roundtrip with intermediate step: Checking details of ndt.png reveals that the detail structure has completely changed)


But I think this may be the problem:

convert -list configure
Look at the line starting with DELEGATES. It should include fftw.

Under DELEGATES I cannot find fftw. This is strange (because I have everything installed on my machine) but probably a configuration problem I was not aware of.

Thanks for the help, I will post if I have solved the problem.
Conrad.

Be sure to compile IM again after installing FFTW. Also see this about installing on Windows FFTW viewtopic.php?f=4&t=14251#p56836