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| Multiplexing I/O module |
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| Modular computer assembly |
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| Ergonomic docking station for a portable computer |
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| High-performance modular memory system with crossbar connections |
| OF THE PREFERRED EMBODIMENTS System Platform FIG. 1 is a block diagram of a Symmetrical Multi-P... |
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| System and method for checking bits in a buffer with multiple entries |
| FIG. 1 shows a computer system 100 having a processor 110, also referred to herein as a controller ... |
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| Control circuitry for data transfer in an advanced data link controller |
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| Enhanced network services using a subnetwork of communicating processors |
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| System and method for providing television services |
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| System for controlling an internally-installed cache memory |
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Video storage
| Details |
Inventors: Bopardikar, Raju C.; Braine, Adrian R.;
Assignee: Discreet Logic Inc. (Quebec, CA)
Primary Examiner: Boccio; Vincent F.
Assistant Examiner:
Attorney, Agent or Firm: Gates & Cooper LLP
Video data in the form of a plurality of digitised frames, is stored on a plurality of magnetic disks. Each image frame is striped across a plurality of disks and redundant parity information, derived from the stripes, is written to an additional disk. Disk failure is detected and in response to this detection missing data is regenerated from the parity information. This allows the transfer of video data in real time to be maintained for output so that the system remains operational. While data is being read in real time, derived-from regenerated data, the regenerated data is written to an operational disk, thereby reprotecting the data in the event of a subsequent failure. Frame supplied to output are labelled as being protected or unprotected and application programs may respond to this status information as considered appropriate. |
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DETAILED DESCRIPTION According to a first aspect of the present invention, there is provided video storage apparatus including storage means, transfer means and processing means, wherein said storage means comprises a plurality of storage of devices configured to store respective stripes of image frames with redundant data derived from said stripes, said transferring means is arranged to transfer image data at substantially image display rate or at a rate greater than said display rate, and said processing means is configured to regenerate lost data from said redundant data during a reading operation and said processing means is configured to write said regenerated data to an operational storage device.
In a preferred embodiment, the storage devices are magnetic disks and each stripe may be written to a respective disk with redundant data being written to a separate disk.
The redundant data may be parity data derived by an exclusive ORing operation.
In a preferred embodiment, output data is written to a frame buffer and two output frame buffers may be provided which alternate in operation, to effect double buffering in which a first buffer is written to randomly from the storage devices and a second buffer is read sequentially as a synchronized video stream.
The video stream may be compatible with D1 video recommendations.
According to a second aspect of the present invention, there is provided a method of storing video data, wherein image stripes derived from image frames in combination with redundant data derived from said stripes are stored on a plurality of storage devices, image data is transferred at substantially image display rate or at a rate greater than said display rate, lost data is regenerated from said redundant data during a reading operation, and said regenerated data is written to an operational storage device while output data is being supplied at said transfer rate.
In a preferred embodiment, errors are detected during the replay of video data and data regeneration is initiated in response to said detection
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I/O Systems 
