Protected Media Decoding System Supporting Metadata

Abstract

Video content is protected using a digital rights management (DRM) mechanism, the video content having been previously encrypted and compressed for distribution, and also including metadata such as closed captioning data, which might be encrypted or clear. The video content is obtained by a system of a computing device, the metadata is extracted from the video content and provided to a video decoder, and the video content is provided to a secure DRM component. The secure DRM component decrypts the video content and provides the decrypted video content to a secure decoder component of a video decoder. As part of the decryption, the secure DRM component drops the metadata that was included in the obtained video content. However, the video decoder receives the extracted metadata in a non-protected environment, and thus is able to provide the extracted metadata and the decoded video content to a content playback application.

1 . A method implemented in a computing device, the method comprising:
 obtaining video content from a media source, the video content including multiple video frames that include metadata as well as protected video content;   extracting the metadata from the multiple video frames;   providing the extracted metadata to a video decoder;   providing the multiple video frames to a secure digital rights management component;   receiving, from the secure digital rights management component, a re-encrypted version of the multiple video frames, the re-encrypted version of the multiple video frames comprising a version of the multiple video frames from which the protected video content has been decrypted and re-encrypted based on a key of the computing device;   providing the re-encrypted version of the multiple video frames to the video decoder for decoding of the re-encrypted version of the multiple video frames rather than decoding of the multiple video frames; and   providing the extracted metadata and the decoded video frames to an application for playback.   
     
     
         2 . The method of  claim 1 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder only if the metadata is clear data. 
     
     
         3 . The method of  claim 1 , the metadata comprising closed captioning data. 
     
     
         4 . The method of  claim 1 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder from a media source component that obtains the video content. 
     
     
         5 . The method of  claim 1 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder from a digital rights management decryptor component that provides the multiple video frames to the secure digital rights management component. 
     
     
         6 . The method of  claim 1 , the providing the multiple video frames to the secure digital rights management component comprising providing, by a digital rights management decryptor component, the multiple video frames to the secure digital rights management component, the digital rights management decryptor component being implemented in an unsecure layer of the computing device and the secure digital rights management component being implemented in a secure layer of the computing device, components in the secure layer having access to one or more keys to decrypt the protected video content, and components in the unsecure layer having no access to the one or more keys to decrypt the protected video content. 
     
     
         7 . A method implemented in a computing device, the method comprising:
 obtaining video content from a media source, the video content including multiple video frames that include metadata as well as protected video content;   extracting the metadata from the multiple video frames;   providing the extracted metadata to a video decoder;   providing the multiple video frames to a secure digital rights management component, the secure digital rights management component decrypting the protected video content and providing the decrypted content to a secure decoder component for decoding of the decrypted content rather than decoding of the multiple video frames; and   providing the extracted metadata and the decoded content to an application for playback.   
     
     
         8 . The method of  claim 7 , the secure digital rights management component and the secure decoder component being implemented as part of a secure layer of the computing device, only components in the secure layer having access to one or more keys to decrypt the protected video content, the providing the multiple video frames to the secure digital rights management component comprising storing the decrypted content in memory of the computing device that is accessible to only components of the secure layer. 
     
     
         9 . The method of  claim 7 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder only if the metadata is clear data. 
     
     
         10 . The method of  claim 7 , the metadata comprising closed captioning data. 
     
     
         11 . The method of  claim 7 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder from a media source component that obtains the video content. 
     
     
         12 . The method of  claim 7 , the providing the extracted metadata to the video decoder comprising providing the extracted metadata to the video decoder from a digital rights management decryptor component that provides the multiple video frames to the secure digital rights management component. 
     
     
         13 . A computing device comprising:
 a media source component configured to obtain video content from a media source, the video content including multiple video frames that include metadata as well as protected video content;   an extraction component configured to extract the metadata from the multiple video frames and provide the extracted metadata to a video decoder;   a secure digital rights management component configured to receive the multiple video frames and provide the protected video content to the video decoder for decoding of the protected video content rather than decoding of the multiple video frames; and   a video decoder component configured to provide the extracted metadata and the decoded content to an application for playback.   
     
     
         14 . The computing device of  claim 13 , the secure digital rights management component being further configured to:
 decrypt the protected video content; and   provide, to the video decoder as the protected video content, the decrypted content.   
     
     
         15 . The computing device of  claim 13 , the secure digital rights management component being further configured to provide, to the video decoder as the protected video content, the protected video content in the multiple video frames as well as one or more keys, and the video decoder component being further configured to decrypt the protected video content. 
     
     
         16 . The computing device of  claim 13 , the extraction component and the media source component comprising the same component. 
     
     
         17 . The computing device of  claim 13 , the extraction component comprising a digital rights management decryptor component that is further configured to receive the multiple video frames from the media source component and provide the multiple video frames to the secure digital rights management component. 
     
     
         18 . The computing device of  claim 13 , the secure digital rights management component being further configured to decrypt the protected content and re-encrypt the decrypted content based on a key of the computing device prior to providing the decrypted content to the video decoder. 
     
     
         19 . The computing device of  claim 13 , the secure digital rights management component being implemented in a secure layer, the extraction component being implemented in an unsecure layer, and only components in the secure layer having access to one or more keys to decrypt the protected video content. 
     
     
         20 . The computing device of  claim 19 , the secure digital rights management component being implemented in hardware.