I have a video application, designed in Qsys v. 16.1.
Had some issues with the "Scaler II (4K ready)". During debug, I have cut away everything else, thus my Qsys design now consists of: Test pattern generator -> Scaler II (Dout is exported for analysis)
Test pattern generator is currently configured as 704x576 pix, RGB, colour bars.
The scaler is currently configured over control-interface to downscale to 176x144.
With this configuration, I get the attached uncompressed image.
In horizontal direction I can downscale 4 times, but anything below 240pix vertical dimension, corrupts the image.
This project was originally built in Quartus 13, sp1, using scaler v. 13.0.1
In that project I could scale to 176x144 without any problems.
I just figured it out.
The down scaled image requires more buffering. I guess this is due to reduced pixel-frequency by the horizontal downscale-factor.
My first solution was to insert a frame-buffer after scaling.