Undesired (incorrect?) behavour of CVI AV-ST output

Niki,

I have seen this post, as well as one other from you. We are using the Altera VIP Suite to implement a video processing system. We accept several different video input formats, and the processor card that feeds us the video stream can change formats without notice, and mid frame (we have no control over this). When we switch between formats, we get the CVI module to hang. This problem is fairly regular, and we have a script that can reproduce it by repeatedly changing the input source every few seconds. The Avalon bus registers indicate that a FIFO overflow has occurred. After this condition occurs, we are unable to get any video through the pipeline, and the system sits there until a hard reset is applied. We have even tried resetting only the CVI module, but this does not seem to work.

It seems to us that the issue is the transition from one format to another which is abrupt, and often accompanied by a frequency change, depending on the input video format. I was wondering if you ever resolved this issue posted above, or your other related issue. We are looking for a work around to this CVI issue, and any help would be greatly appreciated.

Thanks in advance,

Thomas