摘要 |
A video noise reducer comprises a full picture memory and provides comparison of corresponding pixels of undelayed and delayed video signals, in which the delayed signal is fed back and mixed which is the undelayed signal at a controllable fader fading factor controlled by the absolute value difference between compared pixels subjected to filtering and other processing. In this noise reducer pixel comparison is elaborated to provide a signal designating the sign of the difference and a temporal (non-spatial) motion detector checks for the predominance of designations of one sign (and the rarity of designations of the other sign) in order to establish the presence of a fading procedure which must not be mistakenly interpreted as a detection of motion in the picture content. The temporal motion detector can be constituted so that isolated designations of a sign opposite to the preponderant sign of a succession of designations of the same sign cannot prevent the recognition of the presence of a fading procedure.
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