Gaming system file authentication

Abstract

A gaming system utilizes watermarks in files to provide file authentication. In one embodiment, the files contain images or video clips. Selected frames of such images or video clips contain a watermark, which is compared to a key stored in the gaming system. The key may be stored in a non-volatile random access memory in the gaming system. In one embodiment, the memory is not modifiable by a customer.

1 . A gaming machine implemented method comprising: 
 reading a frame from a file;    extracting a watermark from the frame; and    comparing the extracted watermark to a key to authenticate the frame.    
   
   
       2 . The method of  claim 1  wherein the file comprises audio/video information stored on the gaming machine.  
   
   
       3 . The method of  claim 1  wherein a frame or file contains more than one watermark.  
   
   
       4 . The method of  claim 1  wherein the file comprises multiple audio/video frames, and wherein every nth frame contains a watermark, wherein n ranges between approximately 30 to 50.  
   
   
       5 . The method of  claim 1  wherein authentication is performed continuously while reading frames from a file.  
   
   
       6 . The method of  claim 5  and further comprising outputting frames from the files to users of the gaming machine as selected frames are authenticated.  
   
   
       7 . The method of  claim 1  and further comprising stopping execution of a game when an extracted watermark does not successfully compare to a corresponding key.  
   
   
       8 . The method of  claim 1  wherein a small percentage of files are authenticated during a boot of the gaming machine.  
   
   
       9 . The method of  claim 1  wherein at least one frame from each file is authenticated on boot or continuous running of the gaming machine.  
   
   
       10 . The method of  claim 9  wherein the location of a watermark in a file is randomized from file to file.  
   
   
       11 . A method of authenticating a file in a gaming system, the method comprising: 
 reading multiple frames from the file;    extracting a watermark from one of the frames;    comparing the extracted watermark to a key stored on the gaming system to authenticate the frame.    
   
   
       12 . The method of  claim 11  wherein a watermark is stored in one of approximately thirty consecutive frames.  
   
   
       13 . The method of  claim 11  wherein frames have different watermarks.  
   
   
       14 . The method of  claim 13  wherein the different watermarks comprise a sequence of different watermarks that are repeated.  
   
   
       15 . The method of  claim 11  wherein the watermark is encrypted, and wherein extracting the watermark further comprises decrypting the watermark.  
   
   
       16 . The method of  claim 11  wherein the key is stored on a memory device that is not accessible to users of the gaming system.  
   
   
       17 . A computer readable medium having instructions encoded thereon for execution by a gaming machine for implementing a method comprising: 
 reading a frame from a file;    extracting a watermark from the frame; and    comparing the extracted watermark to a key to authenticate the frame.    
   
   
       18 . The method of  claim 17  wherein a file contains multiple frames, and wherein a watermark is stored in one of approximately thirty consecutive frames.  
   
   
       19 . The method of  claim 17  wherein the watermark is encrypted, and wherein extracting the watermark further comprises decrypting the watermark.  
   
   
       20 . The method of  claim 17  wherein the key is stored on a memory device that is not accessible to users of the gaming system.  
   
   
       21 . A computer readable medium having code for execution on a gaming system, the medium comprising: 
 a file having multiple frames containing images for display on the gaming system, selected frames having watermarks corresponding to keys stored on the gaming system, wherein the gaming system extracts the watermarks from the selected frames and compares them to the keys for authentication of the frames in real time.    
   
   
       22 . A gaming machine comprising: 
 a storage device having a read only audio/video file containing multiple frames of audio/video information, selected frames having a watermark;    a read only memory device having keys corresponding to watermarks in the selected frames; and    an authentication module that when executed by the gaming machine, authenticates the selected frames by comparing the watermarks to the keys while outputting the frames to the user.    
   
   
       23 . The gaming machine of  claim 22  wherein the storage device comprises a hard disk drive and the memory device comprises a game compact flash card.  
   
   
       24 . A gaming machine implemented method comprising: 
 reading data from a file;    extracting a watermark from the data; and    comparing the extracted watermark to a key to authenticate the file.    
   
   
       25 . The gaming machine implemented method of  claim 24  wherein the data read from the file is selected from the group consisting of audio, video, still image, executable code, and information stored on the gaming machine.  
   
   
       26 . The gaming machine implemented method of  claim 24  wherein a frame or file contains more than one watermark.  
   
   
       27 . The gaming machine implemented method of  claim 24  wherein a small percentage of files are authenticated during a boot of the gaming machine.  
   
   
       28 . The gaming machine implemented method of  claim 24  wherein multiple files in the gaming system are authenticated, and wherein the location of the watermarks in files is randomized from file to file.