公开(公告)号：US09160362B1

公开(公告)日：2015-10-13

申请号：US14272929

申请日：2014-05-08

Applicant: QUALCOMM Incorporated

Inventor： Amin Ansari ,  Vito Remo Bica ,  Rodolfo Giacomo Beraha

IPC: H03M7/30

CPC classification number: H03M7/3088 ,  H03M7/3086 ,  H03M7/40

Abstract: Lempel-Ziv (LZ)-based data compression employing implicit variable-length distance coding is disclosed. Distances in LZ-based data compression length and distance blocks are implicit variable-length encoded during data compression to avoid padding encoded distances with extra bits (e.g., trailing 0's) that require fewer bits for storage than the number of bits needed to store maximum distance length. This reduces distance bit lengths in compressed output data to further reduce data size. During data compression, a distance table is generated that contains entries each having an assigned base and a number of extra bits to be read in compressed data during data decompression. In this manner, during data decompression, the entries in the distance table can be consulted to determine the number of bits in the variable-encoded distance in the compressed data to be read since the encoded distances can be encoded in the compressed data in fewer bits and without bit padding.

Abstract translation: 公开了采用隐式可变长度距离编码的基于Lempel-Ziv（LZ）的数据压缩。 基于LZ的数据压缩长度和距离块的距离是在数据压缩期间进行隐式可变长度编码，以避免用额外的比特（例如，尾随0）来填充编码距离，这需要比存储最大距离所需的比特数少 长度。 这减少了压缩输出数据中的距离位长度，以进一步减少数据大小。 在数据压缩期间，生成一个距离表，该距离表包含在数据解压缩期间每个具有分配的基数和多个待压缩数据的额外位的条目。 以这种方式，在数据解压缩期间，可以参考距离表中的条目以确定要读取的压缩数据中的可变编码距离中的比特数，因为编码的距离可以以较少的比特被编码在压缩数据中 并且没有位填充。

公开(公告)号：US10120581B2

公开(公告)日：2018-11-06

申请号：US15085399

申请日：2016-03-30

Applicant: QUALCOMM Incorporated

Inventor： Richard Senior ,  Amin Ansari ,  Vito Remo Bica ,  Jinxia Bai

IPC: G06F3/06 ,  H03M7/30

Abstract: Aspects for generating compressed data streams with lookback pre-fetch instructions are disclosed. A data compression system is provided and configured to receive and compress an uncompressed data stream as part of a lookback-based compression scheme. The data compression system determines if a current data block was previously compressed. If so, the data compression system is configured to insert a lookback instruction corresponding to the current data block into the compressed data stream. Each lookback instruction includes a lookback buffer index that points to an entry in a lookback buffer where decompressed data corresponding to the data block will be stored during a separate decompression scheme. Once the data blocks have been compressed, the data compression system is configured to move a lookback buffer index of each lookback instruction in the compressed data stream into a lookback pre-fetch instruction located earlier than the corresponding lookback instruction in the compressed data stream.

公开(公告)号：US09344114B1

公开(公告)日：2016-05-17

申请号：US14832739

申请日：2015-08-21

Applicant: QUALCOMM INCORPORATED

Inventor： Adrienne Milner ,  Amin Ansari ,  Richard Senior ,  Vito Remo Bica

IPC: H03M7/38 ,  H03M7/40 ,  H03M7/48 ,  H03M7/30 ,  H04N19/61

CPC classification number: H03M7/4062 ,  G06F2212/401 ,  H03M7/30 ,  H03M7/3084 ,  H03M7/4006 ,  H03M7/42 ,  H03M7/48 ,  H04N19/423 ,  H04N19/91

Abstract: Data compression systems, methods, and computer program products are disclosed. For each successive input word of an input stream, it is determined whether the input word matches an entry in a lookback table. The lookback table is updated in response to the input word. Input words may be of a number of data types, including zero runs and full or partial matches with an entry in the lookback table. A codeword is generated by entropy encoding a data type corresponding to the input word. The lookback table may be indexed by the position of the input word in the input stream.

Abstract translation: 公开了数据压缩系统，方法和计算机程序产品。 对于输入流的每个连续输入字，确定输入字是否与回溯表中的条目匹配。 响应于输入字更新回溯表。 输入字可以是数据类型的数量，包括零运行，以及与回溯表中的条目的完全或部分匹配。 通过对对应于输入字的数据类型进行熵编码来生成码字。 回溯表可以由输入流中的输入字的位置索引。

公开(公告)号：US20170285939A1

公开(公告)日：2017-10-05

申请号：US15085399

申请日：2016-03-30

Applicant: QUALCOMM Incorporated

Inventor： Richard Senior ,  Amin Ansari ,  Vito Remo Bica ,  Jinxia Bai

IPC: G06F3/06

CPC classification number: G06F3/061 ,  G06F3/064 ,  G06F3/0656 ,  G06F3/0673 ,  H03M7/3086 ,  H03M7/6017 ,  H03M7/6029

Abstract: Aspects for generating compressed data streams with lookback pre-fetch instructions are disclosed. A data compression system is provided and configured to receive and compress an uncompressed data stream as part of a lookback-based compression scheme. The data compression system determines if a current data block was previously compressed. If so, the data compression system is configured to insert a lookback instruction corresponding to the current data block into the compressed data stream. Each lookback instruction includes a lookback buffer index that points to an entry in a lookback buffer where decompressed data corresponding to the data block will be stored during a separate decompression scheme. Once the data blocks have been compressed, the data compression system is configured to move a lookback buffer index of each lookback instruction in the compressed data stream into a lookback pre-fetch instruction located earlier than the corresponding lookback instruction in the compressed data stream.

公开(公告)号：US09331712B1

公开(公告)日：2016-05-03

申请号：US14832732

申请日：2015-08-21

Applicant: QUALCOMM INCORPORATED

Inventor： Adrienne Milner ,  Amin Ansari ,  Richard Senior ,  Vito Remo Bica

IPC: H03M5/00 ,  H03M7/40 ,  H03M7/48

CPC classification number: H03M7/4062 ,  G06F2212/401 ,  H03M7/30 ,  H03M7/3084 ,  H03M7/4006 ,  H03M7/42 ,  H03M7/48 ,  H04N19/423 ,  H04N19/91

Abstract: Data compression systems, methods, and computer program products are disclosed. For each successive input word of an input stream, it is determined whether the input word matches an entry in a lookback table. The lookback table is updated in response to the input word. Input words may be of a number of data types, including zero runs and full or partial matches with an entry in the lookback table. A codeword is generated by entropy encoding a data type corresponding to the input word. The lookback table may be indexed by the position of the input word in the input stream.