Apparatus and method for concealing interpolation artifacts in a video interlaced to progressive scan converter

摘要

Progressive-scan video signals that are generated from interlaced-scan video signals by interpolation may be subject to temporal distortion when the interstitial interpolated lines have a different time reference than the interlaced lines. This distortion may be mitigated by detecting vertical low-frequency spatial distortion in an interpolated video signal and by generating a compensating signal that, when added to the interpolated video signal reduces that vertical low-frequency spatial distortion. A spatial low-pass filter is applied to corresponding pixels of several adjacent lines of the current field of the original interlaced image. Concurrently, a spatial low-pass filter is applied to corresponding pixels of several interpolated lines that are inserted between the lines of the interlaced image to produce the progressive image. At each pixel position, the low-pass filtered values are compared. If the difference between the low-pass filtered values exceeds a predetermined threshold value, a value approximately equal to the difference between the original pixels and the interpolated pixels is added to the interpolated pixel. <IMAGE>