摘要:
A scheme is provided for communicating high rate isochronous data in an MPEG-2 type transport stream in a robust manner. The syntax for the data bitstream also provides for the communication of a data clock increment value to a decoder. The increment value enables a simplified and cost effective approach to the direct digital synthesis of a clock frequency necessary to recover data from the packetized data stream at the decoder. The time resolution for presenting isochronous data presentation units at the decoder is increased by providing a presentation time stamp (PTS) extension to supplement a standard MPEG-2 PTS.
摘要:
The apparent accuracy of a clock circuit used to recover timing and transmitted information signals in a data receiver is improved. A timing relationship inherent in a received signal is detected prior to the acquisition of a timing component embedded in a desired information portion of the received signal. The timing relationship has an accuracy that is greater than the accuracy of the clock circuit. The clock circuit is controlled in response to the timing relationship to operate with an improved range of accuracy. Thereafter, the embedded timing component is acquired and used to control the clock circuit. In an illustrated embodiment, the timing relationship is derived from a symbol rate of the received signal. In an alternate embodiment, the timing relationship is obtained from a separate transmitted reference signal, such as a transmitted television signal.
摘要:
A succession of variable length data packets containing a header portion and data portion are received. Selected data from the data packet headers is stored in designated locations of a header memory. A data packet start address is provided with each stored header portion to designate a location in a data memory for commencing the storage of data contained in a corresponding data packet. The data from the received data packets is stored commencing in the data memory locations designated by the corresponding data packet start addresses. In an illustrated embodiment, the data packets are macroblocks from digitized television frames. A plurality of next data packet position indicators are provided in the data, for use in periodically verifying macroblock boundaries during the receipt of the television data and to provide a rapid recovery from a transmission error affecting the actual or identified length of a macroblock.
摘要:
A desired information stream is recovered from a pair of independent bitstreams transmitted using quadrature modulation. One of the independent bitstreams is altered by an invertible alteration function prior to transmission. The quadrature modulated bitstreams are demodulated at a receiver to provide a demodulated I bitstream and a demodulated Q bitstream. One of the demodulated I and Q bitstreams is tentatively provided for decoding. The tentatively provided bitstream can be optionally inverted. One of the tentatively provided bitstream and the optionally inverted bitstream is decoded if it is desired to recover the bitstream that was not altered by the alteration function prior to transmission. One of the tentatively provided bitstream and the optionally inverted bitstream is decoded after applying the inverse of the alteration function thereto if it is desired to recover the bitstream that was altered by the alteration function prior to transmission. An error rate of data decoded during the decoding step is determined. If the error rate is not acceptable, different choices of the demodulated I and Q bitstreams with and without inversion are tried until an acceptable error rate is obtained.
摘要:
An integrated circuit chip in which alteration of secure data stored in a predetermined location of a memory on the chip may be prevented. In one embodiment, the chip includes a memory having a plurality of memory locations, with a predetermined location being for the storage of unalterable secure data; a memory control logic circuit coupled to the memory by an address bus for causing data to be stored in locations of the memory indicated by address signals provided on the address bus; a fuse element having an initial state and an irreversibly altered state; means coupled to the fuse element for irreversibly altering the state of the fuse element in response to a predetermined control signal; and a decoder coupled to the fuse element, the memory control circuit and the address bus for monitoring the state of the fuse element and said address signals, and for preventing the memory control circuit from causing data to be stored in the predetermined memory location after the state of the fuse element has been altered irreversibly whenever the predetermined memory location is indicated by an address signal on the address bus. In another embodiment, the chip, includes a first memory having a plurality of memory locations, with a predetermined location being for the storage of unalterable secure data; a second memory; means for enabling a data pattern to be stored in the second memory; a memory control logic circuit coupled to the first and second memories for causing data to be stored in the predetermined location of the first memory in response to a write signal whenever the second memory contains a predetermined data pattern; means coupled to the second memory for enabling the contents of the second memory to be erased; a fuse element having an initial state and an irreversibly altered state; and means coupled to the fuse element for irreversibly altering the state of the fuse element in response to a predetermined control signal; wherein the fuse element is coupled to the means for enabling a data pattern to be stored in the second memory so as to enable said data pattern storage only prior to the state of the fuse element being irreversibly altered.
摘要:
A content moving device may provide content to plurality of different user devices using a plurality of different DRM systems. The content moving device provides for registration of the DRM systems associated with the user devices. The content moving device may verify a user device by a DRM ID associated with the user device. A domain size may be used to limit the number of content user devices that may be approved for access.
摘要:
In an embodiment, a content array represents media content available from a media server. The content array, sent by a media server in response to a request, lists content program objects that represent media content to be available from the media server. The media server receives a message for altering a transcoding priority of the selected content program object that represents media content not previously transcoded by the media server, and sends a return code for indicating whether the transcoding priority was successfully altered in response to the message. In a further embodiment, a media server system includes a transcoding queue with references to a plurality of content program objects that include an object method for altering a transcoding priority, and includes a transcoder configured to transcode media content associated with the content program objects according to the transcoding priority of each content program object of the transcoding queue.
摘要:
There is a performing of digital rights management (DRM), operable in an offline mode with respect to a communications network. The performing includes identifying a stored rights object associated with a stored asset. The stored rights object includes reporting duration information associated with the stored asset. The performing also includes determining, utilizing a processor, whether a transmission of an early status message is a successful communication based on an early status message determination. If a failure in communicating the early status message is determined, utilizing the stored asset. The performing may also include transmitting an early status message and/or later status message after identifying the stored rights object. There is also a performing of digital rights management (DRM) associated with a DRM system and operable in an offline mode with respect to a communications network. There are also client devices, communicating systems, computer readable mediums and protocols.
摘要:
In a method for encrypting content, the content is received in a device and at least a portion of the content is stored to thereby associate the content with one of a first copy control state and a second copy control state. The method includes creating at least one of a first content pre-key using a local storage key unique to the device as a key to encrypt the content ID of the content and a second content pre-key using the first content pre-key as a key to encrypt the first copy control state, creating a content encryption key using one of the first content pre-key as a key to encrypt the first copy control state and the second content pre-key as a key to encrypt the second copy control state, and encrypting the content using the content encryption key.
摘要:
In an embodiment, a content array represents media content available from a media server. The content array, sent by a media server in response to a request, lists content program objects that represent media content to be available from the media server. The media server receives a message for altering a transcoding priority of the selected content program object that represents media content not previously transcoded by the media server, and sends a return code for indicating whether the transcoding priority was successfully altered in response to the message. In a further embodiment, a media server system includes a transcoding queue with references to a plurality of content program objects that include an object method for altering a transcoding priority, and includes a transcoder configured to transcode media content associated with the content program objects according to the transcoding priority of each content program object of the transcoding queue.