The latency of the Video Processing Subsystem depends on the configuration of the core. Generally, the latency is on the order of several lines. For example, a vertical scaler with a 6-tap polyphase filter operating on RGB video introduces 4 video lines of delay.
In the Full Fledged configuration with the use of a DMA, the latency is 1 full frame time plus several lines because the video DMA engine is used in the data flow and programmed to read one frame buffer behind the write frame buffer location.
In interlaced video, 1 of field additional delay is incurred by the deinterlacer algorithm.