Refine wcompress settings (lossy to near-lossless).

Hello,

please help me. I am trying to compress a large image data set (512x512x192 px).

Firstly I have a lossless transform block (1D DWT, 2D DWT, 3D DWT, 1D KLT, 2D PCA or combination of them) than I need some quantization and source coding at the end. For the second part I am using wcompress and it works great (compressing 30:1)! But the PSNR is way too low for my application (12dB right now, I need 30 dB minimum). Can anybody help me please?

Official instructions are not very detailed.

https://www.mathworks.com/help/wavelet/ref/wcompress.html