SET DQT via -define jpeg:q-table

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whugemann
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SET DQT via -define jpeg:q-table

Post by whugemann » 2019-03-22T10:01:22-07:00

I have just been experimenting with this option on my Windows computer, running IM 7.0.8-23 Q16 x64:

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magick -size 256x256 -depth 8 -seed 1000 plasma:fractal -define jpeg:q-table="C:\Temp\Erich\table.xml" plasma_my.jpg
checking the DQT afterwards with JPEGsnoop (https://www.impulseadventure.com/photo/jpeg-snoop.html) and additionally with a hexeditor.

The DQT entries are not identical to those provided in the XML-File; there seems to be some sort of scaling going on. Same result for the XML-File provided with IM 7, i.e. quantization-table.xml.

Am I missing some point?
Wolfgang Hugemann

elmo
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Re: SET DQT via -define jpeg:q-table

Post by elmo » 2019-05-12T14:08:03-07:00

I'm having the same problem. Any luck?

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