Using quality (-q) with jp2 (-out jp2) has no effect

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jedijorgie
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Joined: Tue Nov 11, 2003 6:37 am

Using quality (-q) with jp2 (-out jp2) has no effect

Post by jedijorgie » Tue Nov 11, 2003 6:46 am

I cannot get this to work:

nconvert -out jp2 -q 60 -o output.jp2 input.jp2

It creates output.jp2 just fine, but the quality is at 100%. In my tests I can put any number in place of the 60 and it does the same thing.

If I save the file with XnView with a quality setting of 60 the file goes from over 200K to 44k but looks just fine.

How do I get nconvert to save at the '60' quality level?

Jorgie

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xnview
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Re: Using quality (-q) with jp2 (-out jp2) has no effect

Post by xnview » Wed Nov 12, 2003 2:50 pm

Hello,
jedijorgie wrote:I cannot get this to work:
nconvert -out jp2 -q 60 -o output.jp2 input.jp2
It creates output.jp2 just fine, but the quality is at 100%. In my tests I can put any number in place of the 60 and it does the same thing.
If I save the file with XnView with a quality setting of 60 the file goes from over 200K to 44k but looks just fine.
How do I get nconvert to save at the '60' quality level?
Strange, i have tested with NConvert v4.11, and all is ok!
Regards. Pierre.

jedijorgie
Posts: 3
Joined: Tue Nov 11, 2003 6:37 am

that is really strange

Post by jedijorgie » Wed Nov 12, 2003 8:55 pm

I just downloaded and reinstalled. Here is what I am seeing.

I started with http://jorgie.org/initial.jpg which is 266,223 bytes.
I then ran:
nconvert.exe -out jp2 -q 60 -o nconvert60.jp2 initial.jpg

Which created http://jorgie.org/nconvert60.jp2 which is 425,451 bytes!

I then opened that in XnView and saved it as XnView60.jp2 with the quality set to 60.

That created http://jorgie.org/XnView60.jp2 whis is 71,061 bytes!

So I ask again, how do I get nconvert to output the 71,061 version of the file that XnView produces? Am I using the wrong setting with nconvert?

Jorgie

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xnview
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Re: that is really strange

Post by xnview » Thu Nov 13, 2003 8:14 am

Hello,
jedijorgie wrote:So I ask again, how do I get nconvert to output the 71,061 version of the file that XnView produces? Am I using the wrong setting with nconvert?
No, sorry, there is a little bug. Quality is not used (ratio 1:20 is used).
Regards. Pierre.

jedijorgie
Posts: 3
Joined: Tue Nov 11, 2003 6:37 am

whew!

Post by jedijorgie » Thu Nov 13, 2003 8:24 pm

Well at least I know I am not going crazy!!! :)

Any idea when you will get a chance to fix it?

Thanks for the great programs!

Jorgie

artwork

Post by artwork » Fri Mar 19, 2004 11:37 am

It looks like this bug still present in NConvert 4.17.
Any Idea when it`ll be fixed ?
Or is there any other way to pass the quality settings to NConvert ?

Kind Regards,
Markus

artwork

Post by artwork » Fri Mar 19, 2004 11:44 am

And would it be possible that the option -q would be passed to the lwfjp2 format too ?
Seems that this format always uses a quality setting of 100% (when compring the images in Photoshop using Difference)

Markus

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