Uncompress JPEG 2000 lossless image different from original one

[alessandro_c_]

Hello,

I need to create an application that is be able to compress and decompress image in Jpeg 2000 lossless format. So I have integrate IPP libraray  (Package ID: w_ccompxe_2011.10.325 w_ipp_7.0.7.325). I've used UIC to interface my program with IPP library. I notice the following problem:

1) I compress an image (example lena.bmp ) to jpeg 2000 lossless (lena.jp2)

2) I uncompress the image (lena.jp2) to lenauncompress.bmp

3) lenauncompress.bmp is different from the original one lena.bmp. Very little difference but it is important for me that the orginal image and the decompress one are the same image.

 Of course I thought that the problem is on my side.  However i try to do the same procedure (step 1) 2) 3) ) with the application uic_transcoder_con.exe and i see that I've the same problem. In particular i've performed the following step:

a) uic_transcoder_con -i lena.bmp -o lena.jp2 -l 1   (for losslell compression)

b) uic_transcoder_con -i lena.jp2 -o lenauncompress.bmp

lena and lenauncompress are different

I also see that the problem is in the compression step because if I try to perform compression with another library (Openjpeg) and i try to uncompress with IPP all is ok. Moreover if i try to compress with IPP library and uncompress with OpenJpeg i've the same problem

I attach the two files

lena.bmp original one

lenauncompress.bmp the file that i've obtained compress jpeg2000 lossless the original one and then uncompress

thank you for anyone help

Alessandro Ciurlo

[Images removed by Intel® Developer Zone]

[Jeffrey_M_Intel1]

Thank you for your detailed problem report. This is a known issue which has been in UIC's jpeg2000 implementation for quite a while. UIC is a sample, so it is more like a starting point than a fully developed library that is ready to use in a product. I wish I had better news, but it is unlikely that a fix for jpeg2000 lossless encode will be prioritized on a timeline that will be helpful for your current project. Best regards, Jeff