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More compress ratio

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Information:
Type :: IDEA
Status :: OPENED
Assigned to :: nobody

Description:
Dear Michal,
Hello,
What changes have to do in mkjpeg for more compress ratios?
It will be done simply by changing some parameters in the code or it is more complicated.
Thnaks

Comments:

Mattu, Steven Nov 12, 2012
Ok thanks Michal, i'll try that!
Mattu, Steven Nov 9, 2012
Ok thanks Michal, i'll try that!
Mattu, Steven Nov 9, 2012
Hi Michal

I have used Infraview and Jpegsnoop to extract Quantization tables and have got some good results. However my image is always larger than the Infraview version. So far i have not changed the Huffman tables as i am i bit unclear on how to change them, could you help me please with this?

Steve
Krepa, Michal Nov 9, 2012
For Huffman tables you need to modify Header RAM hex file. See 1.10.1 Header RAM Programming in documentation.

Michal
Mattu, Steven Nov 9, 2012
Hi Michal

I have used Infraview and Jpegsnoop to extract Quantization tables and have got some good results. However my image is always larger than the Infraview version. So far i have not changed the Huffman tables as i am i bit unclear on how to change them, could you help me please with this?

Steve
Khaleghian, Mahdi Nov 16, 2010
Thanks
Khaleghian, Mahdi Nov 16, 2010
Thanks
Krepa, Michal Nov 16, 2010
This is done via huffman AC and DC quantization tables.
You can use freely available Irfanview and Jpegsnoop to extract those tables for different quality settings per given image.

Michal

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