2:1 Vertical Reduction

The 2:1 Vertical Reduction filter was designed to reduce the size of each frame by 2:1 in the vertical direction only. A 1x2 non-overlapping matix is used. This filter can also be used to deinterlace. It is MMX optimized.

This filter offers a slight advantage over the VirtualDub resize filters because it does not perform any blurring. Use this filter if you want to maintain absolute maximum sharpness. It is very similar to the 2:1 reduction filter, except that it only works in the vertical direction.

This filter can be used to make good quality VideoCDs by capturing at the 352x480 resolution (interlaced) and then using this filter to downsample to 352x240. Any capture card that uses the Bt848/849 chips should be able to capture at the 352x480 resolution. This filter provides basic deinterlacing and frame height reduction. For better results, place the "smart deinterlace" filter immediately before this filter.