A content-dependent scan rate converter with adaptive
noise reduction that provides a highly integrated, implementation efficient de-interlacer. By identifying and using redundant information from the image (motion values and edge directions), this scan rate converter is able to perform the tasks of film-mode detection, motion-adaptive scan rate conversion, and content-dependent video
noise reduction.
Adaptive video noise reduction is incorporated in the process where
temporal noise reduction is performed on the still parts of the image, thus preserving high detail spatial information, and data-adaptive
spatial noise reduction is performed on the
moving parts of the image. A low-pass filter is used in flat fields to smooth out
Gaussian noise and a direction-dependent
median filter is used in the presence of impulsive noise or an edge. Therefore, the selected
spatial filter is optimized for the particular pixel that is being processed to maintain crisp edges.