new version of PVRTexTool produce poor quality PVRTC image than old version


I downloaded the latest PVRTexTool(4.1.6 (SDK build 3.5@3523712)) a few days ago, and use it to compress png files to PVRTC1_4.
I find that the quality is kind of poor.
One of my friend send me an old version of PVRTexTool(3.23 (SDK build and it seems working much better.
I am confused why newer version works worse than old ones.

The command I was using are: (the first command is for newer version, and the second one is for older version)
PVRTexToolCli -i lossless.png -o aaa_new.pvr -l -f PVRTC1_4 -q pvrtcbest -legacypvr -p
PVRTexTool -i lossless.png -o aaa_old.pvr -f PVRTC4 -q 5 -premultalpha

the source image and result image(converted to PNG) are in the attachments.

  1. lossless.png is original.
  2. aaa_new.png is compressed using new version of PVRTexTool.
  3. aaa_old.png is compressed using old version of PVRTexTool.

My questions are:

  1. why old version works better?
  2. if old version is better, can I download it from anyware?

Thank you.

Thanks for reporting this issue and providing example images. We will discuss this quality regression with the PVRTexTool lead engineer.

Would you please provide me an old version PVRTexTool running on Mac for me? I have only the windows version.

We’ve reproduced the artefacts in the 3.5 SDK PVRTexTool PVRTC compressor. I’ve filed BRN55829 in our issue tracker for this.

If you create a ticket in our support system, we can share a legacy PVRTexTool package with you.

Sorry but I cannot open this URL [URL corrected]
Could you send it to my E-mail address?

To access that page, you must login to the support portal. Registration and private support are provided free of charge.

We would prefer for your request to come through the ticketing system so we can easily assign the task to one of the engineers in our team.

A colleague pointed out I used the wrong URL in my previous posts. I’ve corrected the URLs in this discussion chain. Apologies for any confusion this caused.

That is OK.
I’ve searched by Google and solved.
please see here