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zjlyou / openjpeg

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incorrect encoding or decoding result #493

Open GoogleCodeExporter opened 8 years ago

GoogleCodeExporter commented 8 years ago 
What steps will reproduce the problem?
1.opj_compress  -i ocean3.tif -o ocean3.jp2 -q 40,40,40 -n 11
2.opj_decompress -i ocean3.jp2 -o out.tif
3.use any image viewer to view out.tif. 

What is the expected output? What do you see instead?
out.tif should be very close to image ocean3.tif, but it looks very different 
instead. 

What version of the product are you using? On what operating system?
I am using openjpeg 2.1 on linux  2.6.39-400.211.1.el6uek.x86_64.  

Please provide any additional information below.
I think the key point is parameter "-n 11". If the number of resolution is 10 
or less, the result looks ok. If the number of resolution is great or equal to 
10, the result is not good. 

Note: the attached file is ocean3.jpg because ocean3.tif is larger than 10M. 
Please first uncompress ocean3.jpg to ocean3.tif to run the test case.

Original issue reported on code.google.com by fec...@gmail.com on 19 May 2015 at 6:45

GoogleCodeExporter commented 8 years ago 
Hi fechen,

Seems that the image is mostly black. I guess that PNG shall be less than 10MB. 
In that case, could you check that the issue is still here with PNG & attach 
that file. This will avoid an unnecessary conversion outside of tested 
software. Thanks.

Original comment by m.darb...@gmail.com on 20 May 2015 at 9:01

GoogleCodeExporter commented 8 years ago 
Here is the same image in PNG format. The problem still exists. 
command: 
   opj_compress -i ocean3.png -o ocean3.jp2 -q 40,40,40 -n 11
   opj_decompress -i ocean3.jp2 -o out.tif

The image is mostly black on the left (which is supposed to be the ocean), on 
the top right side it has data (which is supposed to be the land). This is an 
image with only one component. After jp2 compression and decompression, the 
ocean that surrounds the land is not black anymore, it is in gray color, which 
I think is not correct.

Original comment by fec...@gmail.com on 22 May 2015 at 2:07

Attachments:

GoogleCodeExporter commented 8 years ago 
Hi,

I have uploaded the PNG file and the problem still exists. Please take a
look again.

Original comment by fec...@gmail.com on 28 May 2015 at 2:16