Data processing methods and systems

Abstract

Data processing methods and systems for accessing a target sample in a media data stream. The media data stream has a plurality of samples and corresponding sample information recorded in at least one entry, wherein the sample information for a predetermined number of the entries is calculated and the calculated result is stored in at least one cache entry. Target sample information corresponding to the target sample is provided. One of the cache entries is located by comparing the target sample information with the calculated result of respective cache entries. After locating the cache entry, the target sample from the entries is located corresponding to the located cache entry.

1 . A data processing method for accessing a target sample in a media data stream, the media data stream having a plurality of samples and corresponding sample information recorded in at least one entry, the method comprising: 
 providing target sample information corresponding to the target sample, wherein the sample information for a predetermined number of entries is calculated and the calculated result is stored in at least one cache entry;    locating one of the cache entries by comparing the target sample information with the calculated result of respective cache entries; and    after locating the cache entry, locating the target sample from the entries corresponding to the located cache entry.    
   
   
       2 . The method of  claim 1  further comprising determining the number of the cache entries according to the number of the entries.  
   
   
       3 . The method of  claim 1  further comprising calculating the sample information for the respective predetermined number of the entries during playback.  
   
   
       4 . The method of  claim 1  wherein at least one table is provided, wherein the table is a time to sample box (STTS) listing the entries and the corresponding sample information, the sample information comprises a decoding time of samples in the corresponding entry.  
   
   
       5 . The method of  claim 4  wherein the target sample information comprises a specific decoding time.  
   
   
       6 . The method of  claim 5  wherein the specific decoding time is between the accumulated time duration recorded in the cache entries prior to the located cache entry, and the accumulated time duration recorded in the located cache entry.  
   
   
       7 . The method of  claim 1  wherein at least one table is provided, wherein the table comprises a sample to chunk box (STSC), comprising chunks of the media data stream, and the sample information comprises the number of samples in respective chunks.  
   
   
       8 . The method of  claim 7  wherein the target sample number is between the accumulated number of samples recorded in the cache entries prior to the located cache entry and the accumulated number of samples recorded in the located cache entry.  
   
   
       9 . The method of  claim 1  wherein the media data stream is of a MPEG-4 file.  
   
   
       10 . The method of  claim 1 , wherein the media data stream is comprised in an audio file with no metadata.  
   
   
       11 . The method of  claim 10 , wherein the media data stream is comprised in an MP3, AAC, or AMR/AWB file.  
   
   
       12 . The method of  claim 10 , further dividing the media data stream into segments, and determining the number of the cache entries according to the number of the segments.  
   
   
       13 . The method of  claim 10 , wherein the sample information comprises offset information of an end point of the corresponding segment.  
   
   
       14 . The method of  claim 13 , further comprising calculating the offset for the entries during playback.  
   
   
       15 . The method of  claim 10 , wherein the target sample information comprises a specific decoding time.  
   
   
       16 . The method of  claim 10 , wherein the target sample is located by locating one of the cache entries by a binary search, and further locating the target sample within the located segment by a linear search.  
   
   
       17 . The method of  claim 10 , further copying the established cache entries.  
   
   
       18 . The method of  claim 10 , further rewriting the cache entries when another audio file is to be processed.  
   
   
       19 . A machine-readable storage medium comprising a computer program, which, when executed, causes a device to perform a data processing method for accessing a target sample in a media data stream, the media data stream having a plurality of samples and corresponding sample information recorded in at least one entry, the method comprising: 
 providing target sample information corresponding to the target sample, wherein the sample information for a predetermined number of entries is calculated and the calculated result is stored in at least one cache entry;    locating one of the cache entries by comparing the target sample information with the calculated result of respective cache entries; and    after locating the cache entry, locating the target sample from the entries corresponding to the located cache entry.    
   
   
       20 . The storage medium of  claim 19  wherein the method further comprising determining the number of the cache entries according to the number of the entries.  
   
   
       21 . The storage medium of  claim 19  wherein the method further comprising calculating the sample information for the respective predetermined number of the entries during playback.  
   
   
       22 . The storage medium of  claim 19  wherein at least one table is provided, wherein the table is a time to sample box (STTS) listing the entries and the corresponding sample information, the sample information comprises a decoding time of samples in the corresponding entry.  
   
   
       23 . The storage medium of  claim 22  wherein the target sample information comprises a specific decoding time.  
   
   
       24 . The storage medium of  claim 23  wherein the specific decoding time is between the accumulated time duration recorded in the cache entries prior to the located cache entry, and the accumulated time duration recorded in the located cache entry.  
   
   
       25 . The storage medium of  claim 19  wherein at least one table is provided, wherein the table comprises a sample to chunk box (STSC), comprising chunks of the media data stream, and the sample information comprises the number of samples in respective chunks.  
   
   
       26 . The storage medium of  claim 25  wherein the target sample number is between the accumulated number of samples recorded in the cache entries prior to the located cache entry and the accumulated number of samples recorded in the located cache entry.  
   
   
       27 . The storage medium of  claim 19  wherein the media data stream is of a MPEG-4 file.  
   
   
       28 . The storage medium of  claim 19 , wherein the media data stream is comprised in an audio file with no metadata.  
   
   
       29 . The storage medium of  claim 28 , wherein the media data stream is comprised in an MP3, AAC, or AMR/AWB file.  
   
   
       30 . The storage medium of  claim 28 , wherein the method further divides the media data stream into segments, and determines the number of the cache entries according to the number of the segments.  
   
   
       31 . The storage medium of  claim 28 , wherein the sample information comprises offset information of an end point of the corresponding segment.  
   
   
       32 . The storage medium of  claim 31 , wherein the method further comprises calculating the offset for the entries during playback.  
   
   
       33 . The storage medium of  claim 28 , wherein the target sample information comprises a specific decoding time.  
   
   
       34 . The storage medium of  claim 28 , wherein the method further locates the target sample by locating one of the cache entries by a binary search, and further locates the target sample within the located segment by a linear search.  
   
   
       35 . The storage medium of  claim 28 , wherein the method further copies the established cache entries.  
   
   
       36 . The storage medium of  claim 28 , wherein the method further rewrites the cache entries when another audio file is to be processed.  
   
   
       37 . A data processing system, comprising: 
 a media data stream comprising a plurality of samples and corresponding sample information recorded in at least one entry;    at least one cache entry storing a calculated result of the sample information for a predetermined number of the entries; and    a processing unit receiving target sample information corresponding to a target sample, locating one of the cache entries by comparing the target sample information with the calculated result of respective cache entries, and after locating the cache entry, locating the target sample from the entries corresponding to the located cache entry.    
   
   
       38 . The system of  claim 37  wherein the processing unit further determines the number of the cache entries according to the number of the entries.  
   
   
       39 . The system of  claim 37  wherein the processing unit further calculates the sample information for the respective predetermined number of the entries during playback.  
   
   
       40 . The system of  claim 37  wherein at least one table is provided, wherein the table is a time to sample box (STTS) listing the entries and the corresponding sample information, the sample information comprises a decoding time of samples in the corresponding entry.  
   
   
       41 . The system of  claim 40  wherein the target sample information comprises a specific decoding time.  
   
   
       42 . The system of  claim 41  wherein the specific decoding time is between the accumulated time duration recorded in the cache entries prior to the located cache entry, and the accumulated time duration recorded in the located cache entry.  
   
   
       43 . The system of  claim 37  wherein at least one table is provided, wherein the table comprises a sample to chunk box (STSC), comprising chunks of the media data stream, and the sample information comprises the number of samples in respective chunks.  
   
   
       44 . The system of  claim 43  wherein the target sample number is between the accumulated number of samples recorded in the cache entries prior to the located cache entry and the accumulated number of samples recorded in the located cache entry.  
   
   
       45 . The system of  claim 37  wherein the media data stream is of a MPEG-4 file.  
   
   
       46 . The system of  claim 37  wherein the data processing system is a MPEG-4 file decoder.  
   
   
       47 . The system of  claim 37 , wherein the media data stream is comprised in an audio file with no metadata.  
   
   
       48 . The system of  claim 47 , wherein the media data stream is comprised in an MP3, AAC, or AMR/AWB file.  
   
   
       49 . The system of  claim 47 , wherein the processing unit further divides the media data stream into segments, and determines the number of the cache entries according to the number of the segments.  
   
   
       50 . The system of  claim 47 , wherein the sample information comprises offset information of an end point of the corresponding segment.  
   
   
       51 . The system of  claim 50 , wherein the processing unit further calculates the offset for the entries during playback.  
   
   
       52 . The system of  claim 47 , wherein the target sample information comprises a specific decoding time.  
   
   
       53 . The system of  claim 47 , wherein the processing unit further locates the target sample by locating one of the cache entries by a binary search, and further locates the target sample within the located segment by a linear search.  
   
   
       54 . The system of  claim 47 , wherein the processing unit further copies the established cache entries for further use.  
   
   
       55 . The system of  claim 47 , wherein the processing unit further rewrites the cache entries when another audio file is to be processed.