摘要:
A Huffman decoder for decoding data words encoded according to the Huffman coding provisions of either H.261 or MPEG standards, the data words including an identifier that identifies the Huffman code standard under which the data words were coded, comprising means for receiving the Huffman coded data words, including means for reading the identifier to determine which standard governed the Huffman coding of the received data words, and means for converting the data words to JPEG Huffman coded data words, if necessary, in response to reading the identifier that identifies the Huffman coded data words as H.261 or MPEG Huffman coded ; means, operably connected to the Huffman coded data words receiving means, for generating an index number associated with each JPEG Huffman coded data word receiving an index number from the index number generating means, and including an output that is a decoded data word corresponding to the index number.
摘要:
In a system having a data stream including run level code, the improvement characterized by : an interfacing token for control and/or data functions in said data stream, wherein said token comprises a plurality of data words, each said word including an extension indicator which indicates a presence or an absence of additional words in said token, a length of said token being determined by said extension indicators, whereby the length of said token can be unlimited, inverse modeler means active upon said data stream and responsive to said token for expanding out said run level code to a run of zero data followed by a level, whereby each token is expressed with a specified number of values.
摘要:
A method for generating a substituted address in a memory comprising the steps of : providing a first memory having words of predetermined width and composed of partial words ; rotating a partial word to be accessed to a least significant bit justification ; extending a remaining part of a word which contains the partial word so that an accessed word will be recognized as the partial word ; delimiting a substitution field of the partial word with a termination marker, said substitution field being variable in size ; substituting data in all of said substitution field to define a part of an address of a second memory, said address comprising said substituted field and an unsubstituted portion of said partial word ; restoring the remaining part of the word ; and rotating the word until the partial word is restored to its original position.
摘要:
An image formatter for processing encoded video data comprising :
an input element for receiving encoded data having a frame rate and an arrival rate ; a memory defining at least three buffers for storage of the encoded data, one of said buffers being a display buffer, and another of said buffers being an arrival buffer ; a write address generator for generating write addresses for data being stored thereat in said memory ; a read address generator for generating read addresses for reading data stored thereat in said memory ; an output interface linked to said read address generator that produces decoded data at a display rate ; and a buffer manager responsive to said arrival rate, said display rate, and said frame rate for allocating said buffers to said write address generator and said read address generator, wherein said buffers are allocated to said write address generator in response to a timing regime
摘要:
The invention provides a decoder of symbols of received data, the data being encoded according to a convolutional encoding scheme and transmitted through a communications channel. The data is punctuated according to a puncturing matrix, and has a plurality of state values which describe a sequence of state transitions. The decoder has a generation unit that accepts the received data for calculating metrics of the transitions thereof. A selector responsive to the generation unit selects a path of transitions corresponding to the path produced by a transmitter of the data stream. A traceback unit maintains historical information representative of sequential decision operations of the selector. A counter is provided for counting illegal state transitions of the path selected by the selector, and a control unit, responsive to the counter, determines a puncture rate and adjusts a puncture phase of the received data. The decoder can be used in a VLSl receiver circuit which is adapted to the reception of QPSK modulated data.
摘要:
In a system having an input and an output and a plurality of processing stages between the input and the output, the improvement comprising : an interactive interfacing token, defining a universal adaptation unit for control and/or data functions among said processing stages ; and one of said stages receiving said input and adapted to generate and/or convert said tokens , and wherein said one of said stages detects overlapping start codes , whereby the first start code is ignored and the second start code is used to create start code tokens.
摘要:
In a system having an input and an output and a plurality of processing stages between the input and the output, the improvement comprising :
an interactive interfacing token, defining a universal adaptation unit for control and/or data functions among said processing stages ; and one of said stages receiving said input and adapted to generate and/or convert said tokens , and wherein said one of said stages detects overlapping start codes , whereby the first start code is ignored and the second start code is used to create start code tokens.
摘要:
The present invention is directed to a number of techniques for addressing and accessing memory, including accessing from RAM a number M of words that is less than the predetermined fixed burst length N of the RAM. Also disclosed is a method for accessing Dynamic Random Access Memory (DRAM) to store and retrieve data words associated with a two dimensional image, and a procedure for providing a word with fixed width, having a fixed number of bits to be used for addressing variable width data, and having a width defining field and address field, is disclosed. There is also disclosed a method to control the buffering of encoded video data organized as frames or fields. This method involves determining the picture number of each incoming decoded frame, determining the expected presentation number at any time and marking any buffer as ready when its picture number is on or after the presentation number. Finally, there is disclosed a RAM interface for connecting a bus to RAM wherein a separate address generator generates the addresses the RAM interface needs to address the RAM. The address generator communicates with the RAM interface via a two wire interface.
摘要:
The invention provides a decoder of symbols of received data, the data being encoded according to a convolutional encoding scheme and transmitted through a communications channel. The data is punctuated according to a puncturing matrix, and has a plurality of state values which describe a sequence of state transitions. The decoder has a generation unit that accepts the received data for calculating metrics of the transitions thereof. A selector responsive to the generation unit selects a path of transitions corresponding to the path produced by a transmitter of the data stream. A traceback unit maintains historical information representative of sequential decision operations of the selector. A counter is provided for counting illegal state transitions of the path selected by the selector, and a control unit, responsive to the counter, determines a puncture rate and adjusts a puncture phase of the received data. The decoder can be used in a VLSl receiver circuit which is adapted to the reception of QPSK modulated data.