System and method for caching multimedia data

Abstract

Systems and methods are provided for caching media data to thereby enhance media data read and/or write functionality and performance. A multimedia apparatus, comprises a cache buffer configured to be coupled to a storage device, wherein the cache buffer stores multimedia data, including video and audio data, read from the storage device. A cache manager coupled to the cache buffer, wherein the cache buffer is configured to cause the storage device to enter into a reduced power consumption mode when the amount of data stored in the cache buffer reaches a first level.

What is claimed is: 
     
         1 . A method of controlling a multimedia storage device, the method comprising:
 providing a mass storage device with a multiplicity of blocks of multimedia data stored thereon;   storing said plurality of blocks of multimedia data read from said mass storage device into a cache memory responsive to a read request for one of the plurality of blocks of multimedia data;   receiving a scan command; and   if said multimedia data corresponding to said scan command is stored in said multimedia cache, transferring said corresponding multimedia data from said cache memory to a track buffer for subsequent rendering.   
     
     
         2 . The method according to  claim 1  further comprising:
 receiving a second scan command; 
 reading multimedia data corresponding to said second scan command from the mass storage device when said multimedia data corresponding to the second scan command is not stored in said cache memory. 
 
     
     
         3 . The method according to  claim 1 , wherein sub-band data is stored in said cache memory in synchronization with said plurality of blocks of multimedia data. 
     
     
         4 . A method of controlling a multimedia storage device, the method comprising:
 providing a storage drive with a multiplicity of blocks of multimedia data stored thereon;   providing a cache memory and a track buffer;   transferring said plurality of blocks of multimedia data read from said storage drive into said cache memory and from said cache memory to said track buffer responsive to a read request for one of the plurality of blocks of multimedia data;   transferring additional blocks of said plurality of blocks of multimedia data anticipated being subject to future read requests to substantially fill said cache memory for transfer to said track buffer;   placing said storage drive in a reduced power consumption mode responsive to said cache memory being filled with a plurality of untransferred blocks of multimedia data to a first threshold level;   taking said storage drive out of said reduced power consumption mode responsive to said plurality of untransferred blocks of multimedia data being below a second threshold level; and   replacing blocks of transferred multimedia data in accordance with a priority hierarchy based on at least one characteristic of said blocks of multimedia data.   
     
     
         5 . The method as defined in  claim 4 , further comprising:
 receiving a scan command; and   if said multimedia data corresponding to said scan command is stored in said cache memory, transferring said corresponding multimedia data from said cache memory to said track buffer for subsequent rendering.   
     
     
         6 . The method as defined in  claim 5 , wherein said scan command is one of a fast forward command and a fast reverse command. 
     
     
         7 . The method as defined in  claim 5 , further comprising:
 receiving a second scan command; and   reading multimedia data corresponding to said second scan command from said rotating media storage device when said multimedia data corresponding to the second scan command is not stored in said cache memory.   
     
     
         8 . The method as defined in  claim 4 , wherein sub-band data is stored in said cache memory in synchronization with said plurality of blocks of multimedia data. 
     
     
         9 . The method as defined in  claim 4 , wherein said corresponding multimedia data is transferred from said cache to said track buffer by modifying a pointer value. 
     
     
         10 . A method of processing multimedia data, comprising:
 determining that multimedia data is to be read from a storage device;   transferring a quantity of multimedia data from said storage device to a cache memory responsive to a read request for a first portion of said quantity of multimedia data, a remaining portion of said quantity of multimedia data being multimedia data anticipated being subject to future read requests;   responsive to said first quantity of said multimedia data being stored in said cache memory, ceasing further transfer of said multimedia data from said storage device into said cache memory and causing said storage device to spin down and thereby enter into a power saving mode;   sequentially writing portions of said quantity of multimedia data from said cache memory to a track buffer for subsequent rendering; and   at least partly in response to a portion of said quantity of multimedia data yet to be written to said track buffer stored in said cache memory falling below a threshold value, causing said rotating media storage device to spin up and thereby exit said power saving mode.   
     
     
         11 . The method as defined in  claim 10 , wherein said remaining portion of said quantity of multimedia data includes a plurality of views of at least one image stored in said cache memory. 
     
     
         12 . The method as defined in  claim 10 , wherein the step of sequentially writing is followed by the step of maintaining said quantity of multimedia data in said cache memory subsequent to being rendered for facilitating a scan command without rereading said multimedia data stored on said storage device. 
     
     
         13 . The method as defined in  claim 10 , wherein the step of sequentially writing includes the step of maintaining a DVD menu in said cache memory during playback of a movie stored on said storage device so that said DVD menu can be accessed without rereading said DVD menu from said storage device. 
     
     
         14 . The method as defined in  claim 10 , wherein said remaining portion of said quantity of multimedia data includes menu data and video data.