Input data format autodetection systems and methods

A method of determining a data type of a stream of data in a stream processing device, the data type selected from a group comprising a first type identified by embedded encoded words of information and a second type without embedded encoded words of information, comprising the steps of storing a first word of data in a first buffer and initiating a detection loop;

• storing a second word of data in a second buffer, the second word of data being a word stored in the first buffer during a previous loop;
• checking the words stored in the first and second buffers for the encoded words identifying a datastream of the first data type;
• incrementing a first counter when the words stored in the buffers comprise the encoded words identifying data of the first data type;
• incrementing a second counter when the words stored in the buffers do not identify data of the first data type;
• when the count in the first counter reaches a predetermined value, performing the substeps of:
• determining if a current routine being run is compatible with the first data type,
• processing the datastream of the first data type with the current routine if the current routine is compatible with the first data type;
• and
• when the count in the first counter is below the predetermined value, checking the words of data stored in the first and second buffers for the second type of data;
• and
• when the count in the second counter reaches a predetermined value clearing the first counter and checking the first and second buffers for the second type of data.

A method of processing a data stream comprising the steps of:

• determining if selected words in the stream comprise a set of IEC61937 preambles;
• if the selected words comprise a set of IEC61937 preambles, checking if an application being run is compatible with a type of associated compressed data identified by the preambles;
• if the type of data and the application are compatible, searching for sync words for the type of associated compressed data;
• and
• if the sync words are found, decoding a frame of compressed data.

A method of detecting a change in a data stream from PCM data to data of another format comprising the steps of:

• receiving a stream of words;
• checking whether the words comprise part of a stream of constants;
• checking whether the words comprise part of a stream in a format other than PCM, comprising the substeps of:
• checking whether the words include IEC61937 preambles;
• if the words do not include IEC61937 preambles, checking whether the words include DTS_LD sync words;
• if the words do not include DTS_LD sync words, checking whether the words include DTS_CD sync words;
• and
• if the words are in a format other than PCM performing the substeps of:
• determining if a currently running processing routine is compatible with the format;
• processing the words in accordance with such format with the currently running routine if the currently running routine is compatible with the format;
• processing the first and second words as left and right channel PCM data if the words are not constants and are in a PCM format.

An decoder comprising:

• an input for receiving a stream of data, a format type of the data selected from a group comprising a first format type identified by embedded encoded words of information and a second format type without embedded encoded words of information;
• circuitry for automatically detecting a presence of said embedded words to determine the format type of said data stream;
• and
• circuitry for determining if the format type of the data stream is compatible with a current application being run by said decoder.

The decoder of claim 26 wherein said circuitry for automatically detecting is operable to:

• receive said stream of words;
• check whether first and second words of said stream comprise part of a stream of constants;
• check whether the words comprise part of a stream in a format other than PCM;
• if the words are in a format other than PCM, process the words in accordance with such detected format;
• and
• processing the first and second words as left and right channel PCM data if the words are not constants and are in a PCM format.

A digital processing system comprising:

• source of a stream of digital data, said stream of data being in a format selected from a group including a first format including embedded identifiers and a second format;
• a decoder for receiving and processing said stream in response to an application, said decoder operable to automatically check for said embedded identifiers to identify said format and determine if said format is compatible with a currently running application;
• and
• a host processor for downloading said application to said decoder said currently running application is incompatible with said format.