JamieG Analysis

Hi,

Today I want to bring to light a bug in rhozet and Procoder (all versions including th new V3).

It appears that Procoder introduces a colour space compression on encoded files. This compression is a typical one used to bring the video signal into a safe levels for typical cathode ray tube display. In effect it brings the whites up a little and black down a little. Ie so no black blacks or white whites.

This is all well and good considering the past, however, as very few displays have this restriction. (Ie few Tube displays left.) and really, if I want this safe levels feature, I should have a choice to turn it on or off.

You can, however, use a filter called 601-shrink colour space. In effect, it adjusts the colour space before its encoded as so after it is encoded it comes up with a similar range of colour. However, this squash/stretching of the colour space introduces banding and other unwanted artefacts which again, make it unacceptable.

To help people understand, I have made some images to demonstrate the problem.

Note: I also include mainconcept encoder in the test to show rhoset what SHOULD result from the test.

They can be found at.

http://www2.digitall.net.au/CanopusTests/

I have been talking to rhozet about this for a while. I also spent some time making these tests to show them.

They have not bothered to download them, as such, its time to let the world know.