Abstract: A process and apparatus for converting an MPEG-2 bitstream into an SMPTE-259 compatible bitstream is characterized by a frame rate converter which is selectively enabled to drop every 1001st frame of the incoming MPEG-2 bitstream depending on the input bitstream frame rate. If the input bitstream frame rate is other than 29.97 or 59.94 Hz, a frame dropper is enabled to discard every 1001st frame. The present converter can convert many different types of input bitstreams, such as all I types, IPIP types, or complex GOP types containing I, P, and B frames. The enabled frame dropper will drop either the I or P frame if it occurs as the 1001st frame, but if the 1001st frame is of the B frame type, the pixel information of the B frame is dropped. This produces a minimum in loss of information during the conversion. The format converter allows existing SMPTE-259 routing equipment to route and utilize MPEG-2 bitstreams, such as HDTV applications.

Abstract: A higher order phase loop filter includes an integrator consisting of an adder (25) and a delay element (31) arranged in a feedback loop between the output port of such adder and one of its input ports. Signal to be filtered is applied to a second input port of the adder. A detector (30) is coupled to the output of the adder to detect limiting values, which, when detected, conditions the detector to reset the current value in the delay element of the integrator to a fixed value such as zero. Resetting the delay element momentarily lowers the order of the filter and speeds system response time in the presence of noise.