Patent ID: 6144415
Filing Date: 2000-11-07
Classification: H04N

Abstract:
Apparatus for combining an auxiliary image and a main image, comprising:a source of a main image signal;a source of samples representing an auxiliary image signal having successive fields;a quincunx subsampler, coupled to the auxiliary image sample source, for selectively subsampling the auxiliary image samples in one of a first sample pattern taking samples at a first set of horizontal locations and a second sample pattern taking samples at a second set of horizontal locations substantially midway between the first set of horizontal locations in response to a control signal;a signal combiner, coupled to the quincunx subsampler and the main image signal source, for combining the main image signal and a signal representing the quincunx subsampled auxiliary image samples to generate a combined image signal; anda control circuit, for generating the quincunx subsampler control signal conditioning the quincunx subsampler to take samples in one of the first and second sample patterns at the beginning of each auxiliary image signal field, and in the other one of the first and second sample patterns after a switch time calculated so that the quincunx subsampled auxiliary image samples represented in the combined image signal all are taken by the same sample pattern.