US Patent 10128868 Efficient dictionary for lossless compression

Various systems and methods for lossless data compression are described herein. A process for lossless data compression includes hashing an input byte stream to produce a hash key; identifying a set of dictionary entries in a hash table using the hash key, the hash key associated with a word from a compact dictionary; identifying a set of candidate words from the compact dictionary based on the identified set of dictionary entries, the compact dictionary being a subset of a standard dictionary; determining a best match of the set of candidate words with the input byte stream; and encoding the best match of the set of candidate words as a compressed output of the input byte stream, the encoding including an operation to determine an index into the standard dictionary of the best match and using the index in the encoding operation.