General Information

The number of DVE channels that can be used in Viz Engine depends on the video hardware. The limiting factor is the amount of memory on the card, but also the available bandwidth for transfers between the FPGA and the on-board memory. For example, on a Matrox X.mio 3 / DSX LE 4 card, you can scale eight 1080i surfaces to 99.9% and compose those eight surfaces at the same time. If the scaling factor is reduced, the overall DVE performance increases, due to the lowered amount of bandwidth needed. At a certain point, it might even be possible to add an additional DVE input. Looking at a single channel system fit with an X.mio3, nine inputs can be used as DVE, as one is always consumed by the background layer. However, setting the system up as dual channel, reduces the amount of DVE layers to three in each channel, considering that two background layers are used.