US Patent 7176977 Frame rate conversion of interlaced and progressive video streams

A method and system for deinterlacing an interlaced video stream is presented. The method and system determines whether an interlaced video stream is a normal mode video stream or a special mode video stream. Special mode video streams, which interlaced video streams created from a progressive original video stream, are deinterlaced using special mode deinterlacing, which involves merging two fields to form a frame. Normal mode video streams are deinterlaced using normal mode deinterlacing, which involves converting a field into a frame using line repeating or some form of interpolation to generate the missing scan lines.