differences between them? (about jpeg2000)

[Jinny]

What are the differences between jpeg2000 file format and jpeg2000 format?

I installed XnView ver 2.13 and I converted some png files to jp2.

There are two selections about jp2, which are, jpeg2000 file format and jpeg2000 format.

I converted png images to jp2 using both of them(jpeg2000 file format, jpeg2000 format) but their PSNR values were totally different.

And there are some images which are not converted(errors) when I use jpeg2000 format to convert.

But all the images were completely converted when I use jpeg2000 file format.

[cday]

From XnView 2.00 the JPEG2000 plug-in was changed to OpenJPEG from the previous Xjp2.dll but if you have upgraded from an earlier version of XnView the original plug-in remains installed in the Plugins folder and can only be removed manually.

Please see this thread:

http://newsgroup.xnview.com/viewtopic.php?f=35&t=28236

@ Anyone : The PSNR issue...

Edit:

I see that the same issue also applies to XnViewMP so the Xjp2.dll plugin can also be deleted there if desired.

[XnTriq]

I still have xjp2.dll and openjp2.dll plugins, can I simply delete the former? I also still have a vintage 2009 xdjvu.dll, can I keep that?

xjp2.dll can be removed, xdjvu.dll is you have djvu files

Plug-ins for file formats using wavelet-based image compression:

Code: Select all

+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
| openjp2.dll            | JP2 - JPEG-2000 Format               | OpenJPEG   |                 | R&W |                 |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|               Xjp2.dll | JP2 - JPEG-2000 JP2 File Format      | JasPer     | jp2;j2k;jpx;jpf | R&W | jp2000.zip      |
|                        | JPC - JPEG-2000 Code Stream          |            |             jpc | R&W |                 |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
| lwf_jp2.dll            | JP2 - LuraWave JPEG-2000 Format      | LuraTech   |                 | R&W | jpg2000_lwf.zip |
|                        | JPC - LuraWave JPEG-2000 Code Stream |            |                 | R&W |                 |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|     lwf.dll            | LWF - LuraWave                       | LuraTech   |                 | R&W | lwf.zip         |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|     ldf.dll            | LDF - LuraDocument                   | LuraTech   |                 | R&W | ldf.zip         |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
| ldf_jpm.dll            | JPM - LuraDocument.jpm               | LuraTech   |                 | R&W | ldf-jpm.zip     |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|   WaveL.dll + Xiwc.dll | IWC - WaveL                          |            |             iwc | R&W | iwc.zip         |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
| JWICLIB.DLL + Xwic.dll | WIC - J Wavelet Image Codec          |            |             wic | R&W | wic.zip         |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|              Xdjvu.dll | DJVU - DjVu                          | LizardTech |    djvu;djv;iw4 | R   | djvu.zip        |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+
|             XMrSid.dll | SID - MrSid                          | LizardTech |             sid | R   | mrsid.zip       |
+------------------------+--------------------------------------+------------+-----------------+-----+-----------------+

• Tools » Options... » General » Read/Write » Write
• Info » Plug-Ins Information...
• xnview.ini » [Plugins]

<!--// @Pierre: Is that info correct for XnView Classic v2.13? //-->

• Wikipedia
  • JPEG 2000 » Wavelet transform
  • Wavelet transform » Wavelet compression
  • OpenJPEG
  • JasPer
  • LuraTech
  • Peak signal-to-noise ratio (PSNR)
• Softpedia
  • GIPSA-lab: PSNR
  • RGBchannel: PhotoDefiner PSNR Calculator

[xnview]

<!--// @Pierre: Is that info correct for XnView Classic v2.13? //-->

yes

[cday]

The OpenJPEG plug-in is intended to replace the Xjp2.dll plug-in originally included with XnView software. If both are installed there are two entries in the Save As... list of available file formats, with no clear indication as to which entry corresponds to which plug-in. It would be necessary to remove the plug-ins one at a time to determine that.

Jinny reported that the plug-ins produce JPEG2000 images with different PNSR values and that one plug-in didn't convert all images, but the plug-in concerned wasn't identified and so far no-one has commented on either reported issue.

THe OpenJPEG plug-in is produced by http://www.openjpeg.org and has a brief Wikipedia entry http://en.wikipedia.org/wiki/OpenJPEG .

XnView hasn't given a reason for changing the JPEG2000 plug-in included, and with no confirmed issue with either plug-in ultimately users are free to decide which to use based on their own experience. Sorry I can't do more than recap the known facts!

[cday]

Please see also the continuation of this topic in a new thread:

http://newsgroup.xnview.com/viewtopic.php?f=36&t=29274

[Drahken]

"Jpeg-2000 jp2 file format" is the old/jasper plugin.