Abstract: Two encoders are used in cascade wherein one encoder functions as a preprocessor for the other by collecting statistics concerning partially processed input data. The statistics thus derived are autonomously transferred to a second decoder in a self-synchronized manner, avoiding any need for external glue logic, and utilized to select encoding options for encoding and/or compressing the data so that the quality of encoded data is optimized based on the content of current input data.

Abstract: Two encoders are used in cascade wherein one encoder functions as a preprocessor for the other by collecting statistics concerning partially processed input data. The statistics thus derived are autonomously transferred to a second decoder in a self-synchronized manner, avoiding any need for external glue logic, and utilized to select encoding options for encoding and/or compressing the data so that the quality of encoded data is optimized based on the content of current input data.

Abstract: An apparatus and method for synchronizing multiple circuits or chips clocked at a divided phase lock loop (PLL) frequency. The apparatus generally includes a plurality of chips, each chip including a phase locked loop (PLL) and a circuit for generating a system clock signal, a circuit for receiving the lock signal from each PLL and for generating an All-Locked signal in response to all of the PLLs achieving lock, and a synchronizing circuit for synchronizing the system clocks of the plurality of chips upon receipt of the All-Locked signal.

Abstract: An apparatus and method for extracting vertical (V-SYNC) and horizontal (H-Blank) sync signals from a digital composite sync signal (C-SYNC) of a master video source for use in controlling a second video source, which allows for an adjustable delay relationship between the C-SYNC from the master source and the generated H-Blank. The present invention also provides a system and method for varying the responsiveness or gain of the genlocking circuit used to synchronize the system pixel clock frequency of the second video source to that of the master video signal.

Abstract: A method to compensate for a fade in a digital video input sequence is provided where the video input sequence is to be compressed according to the MPEG-2 video compression standard. The method comprises a first step of dividing each frame of a current frame into two fields. In a second step, each field of the current frame is divided into at least one field band. In a third step, the luminance and chrominance pixel values are individually summed for the pixels in each field of the current frame. In a fourth step, the luminance pixel values are summed for the pixels in each field band of the current frame. In a fifth step, each respective field band sum and field sum of the current frame is compared with that of the previous frame in the video input sequence. In a sixth step, detection of whether or not a fade has occurred is provided, based upon the comparison in the fifth step. In a seventh step, the encoding algorithm is adjusted if a fade has occurred.

Abstract: A cache storage system is disclosed which has a high speed buffer (cache), a directory-look-aside-table, and apparatus for maintaining binary coded information signifying the order of use of various sections of the cache. A separately addressable and controllable storage array is provided for each bit position of the binary code so that updating of a code is accomplished by selectively writing certain but not all of the bits in the arrays storing said bits to be updated. This avoids the need to read all bits from an array, change the appropriate bits, then write all bits back into the array. Bits signifying the changed or unchanged state of data in said various sections of the cache are also stored in separately addressable arrays to permit updating of their value merely by selectively writing to the appropriate array.