Abstract: 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 converted mode video stream. Converted mode video streams, which are interlaced video streams created from an original progressive video stream, are deinterlaced using converted mode deinterlacing, which involves merging two fields to form a frame. Normal mode interlaced 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.