Patent US5502494A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5502494A Expired / Lapsed US ⏱️ 0.0 years remaining

Management of channel buffer in video decoders

Assignee: BS&B Safety Systems Ltd
•
Filing: 1995-03-13
•
Granted: 1996-03-26
•
Expires: 2015-03-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A novel channel buffer management scheme for a video decoder minimizes the amount of memory allocated to buffer a video bitstream received from a transmission channel. A channel buffer accumulates picture data encoded in a video bitstream received from a fixed rate channel. Picture data is read out of the channel buffer by a video decoder immediately after a predetermined or expected amount of bitstream data is received by the channel buffer. Picture decoding, reconstructing, and displaying operations are synchronized to permit the transfer of picture data from the channel buffer to the decoder whenever all of the data bits comprising a picture are received in the channel buffer. A microcontroller monitors and regulates the operation of the novel channel buffer management scheme to avoid overflow or underflow of bitstream data in the channel buffer. In accordance with one aspect of the present invention, a display controller and picture reconstruction means are fabricated as an monolithic integrated circuit device.

Inventors

  • 👤 David R. Auld

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 15:50
CPC Classifications
H; H04; H04N; H04N21/00; H04N21/40; H04N21/43; H04N21/44; H04N21/44004; H04N19/00; H04N19/10; H04N19/134; H04N19/146; H04N19/152; H04N19/42; H04N19/423; H04N19/426; H04N19/427; H04N19/60; H04N19/61; H04N21/4302; H04N21/438; H04N21/4382; H04N19/50

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 150 words
A Motion Picture Experts Group (MPEG) video data transmission system, comprising: a transmitter including an encoder for encoding video data in accordance with an MPEG standard to produce an encoded video bitstream including motion compensated pictures and Discrete Cosine Transform (DCT) encoded pictures; a communications channel for transmitting said video bitstream from the transmitter; and a receiver for receiving said video bitstream from the communications channel, the receiver including: a buffer for temporarily storing said video bitstream; a processor for processing said video bitstream and determining therefrom a number of bits in a picture being stored in the buffer; a reconstruction unit for reconstructing said motion compensated pictures and said DCT encoded pictures; and a controller for causing said picture being stored in the buffer to be transferred from the buffer to the reconstruction unit when said number of bits of said video bitstream has been stored in the buffer.
Claim 2
Dependent Claim 150 words
A Motion Picture Experts Group (MPEG) video data transmission system, comprising: a transmitter including an encoder for encoding video data in accordance with an MPEG standard to produce an encoded video bitstream including motion compensated pictures and Discrete Cosine Transform (DCT) encoded pictures; a communications channel for transmitting said video bitstream from the transmitter; and a receiver for receiving said video bitstream from the communications channel, the receiver including: a buffer for temporarily storing said video bitstream; a processor for processing said video bitstream and determining therefrom a number of bits in a picture being stored in the buffer; a reconstruction unit for reconstructing said motion compensated pictures and said DCT encoded pictures; and a controller for causing said picture being stored in the buffer to be transferred from the buffer to the reconstruction unit when said number of bits of said video bitstream has been stored in the buffer.
Claim 3
Dependent Claim 39 words
A system as in claim 1, in which the reconstruction unit comprises a decoder which includes: a motion pipeline for decoding said motion compensated pictures; and an Inverse Discrete Cosine Transform (IDCT) pipeline for decoding said DCT encoded pictures.
Claim 4
Dependent Claim 33 words
A system as in claim 1, in which: the receiver further comprises a display unit for displaying said pictures; and the controller further synchronizes the buffer, the display unit and the reconstruction unit.
Claim 5
Dependent Claim 34 words
A system as in claim 3, in which the controller causes the display unit to display a first picture while the reconstruction unit reconstructs a second picture and the buffer stores a third picture.
Claim 6
Dependent Claim 32 words
A system as in claim 1, in which the processor comprises means for calculating said number of bits from data included in a header of said picture being stored in the buffer.
Claim 7
Dependent Claim 22 words
A system as in claim 5, in which said data comprises a bit rate parameter and a video buffering verifier delay parameter.
Claim 8
Dependent Claim 25 words
A system as in claim 1, in which the processor comprises means for determining said number of bits by counting bits of said video bitstream.
Claim 9
Dependent Claim 119 words
A Motion Picture Experts Group (MPEG) video data receiver for receiving a video bitstream which is encoded in accordance with an MPEG standard and includes motion compensated pictures and Discrete Cosine Transform (DCT) encoded pictures, the receiver comprising; a buffer for temporarily storing said video bitstream; a processor for processing said video bitstream and determining therefrom a number of bits in a picture being stored in the buffer; a reconstruction unit for reconstructing said motion compensated pictures and said DCT encoded pictures; and a controller for causing said picture being stored in the buffer to be transferred from the buffer to the reconstruction unit when said number of bits of said video bitstream has been stored in the buffer.
Claim 10
Dependent Claim 119 words
A Motion Picture Experts Group (MPEG) video data receiver for receiving a video bitstream which is encoded in accordance with an MPEG standard and includes motion compensated pictures and Discrete Cosine Transform (DCT) encoded pictures, the receiver comprising; a buffer for temporarily storing said video bitstream; a processor for processing said video bitstream and determining therefrom a number of bits in a picture being stored in the buffer; a reconstruction unit for reconstructing said motion compensated pictures and said DCT encoded pictures; and a controller for causing said picture being stored in the buffer to be transferred from the buffer to the reconstruction unit when said number of bits of said video bitstream has been stored in the buffer.
Claim 11
Dependent Claim 39 words
A receiver as in claim 8, in which the reconstruction unit comprises a decoder which includes: a motion pipeline for decoding said motion compensated pictures; and an Inverse Discrete Cosine Transform (IDCT) pipeline for decoding said DCT encoded pictures.
Claim 12
Dependent Claim 30 words
A receiver as in claim 8, further comprising a display unit for displaying said pictures, in which the controller further synchronizes the buffer, the display unit and the reconstruction unit.
Claim 13
Dependent Claim 34 words
A receiver as in claim 10, in which the controller causes the display unit to display a first picture while the reconstruction unit reconstructs a second picture and the buffer stores a third picture.
Claim 14
Dependent Claim 32 words
A receiver as in claim 8, in which the processor comprises means for calculating said number of bits from data included in a header of said picture being stored in the buffer.
Claim 15
Dependent Claim 22 words
A receiver as in claim 12, in which said data comprises a bit rate parameter and a video buffering verifier delay parameter.
Claim 16
Dependent Claim 25 words
A receiver as in claim 8, in which the processor comprises means for determining said number of bits by counting bits of said video bitstream.

References Cited (Backward Citations)

US5148272A Cited
US5379356A Cited
US5283646A Cited
US5398072A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-03-26 1999-09-25 2000-03-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-03-26 2003-09-25 2004-03-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-26 2007-09-25 2008-03-26 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag