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US4888768A Expired / Lapsed US ⏱️ 0.0 years remaining

Frame format for video codec

Assignee: Grass Valley Group Inc
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Filing: 1987-07-06
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Granted: 1989-12-19
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Expires: 2007-07-06
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Abstract

Abstract A frame format for a video codec combines video data at a video subcarrier frequency with up to five data channels at a DS1 digital telecommunications data rate and an optional audio/telephone channel. Video data is sampled and input to a stuff FIFO at the subcarrier frequency rate and output to a multiplexer at a DS3 digital telecommunications data rate. A stuff word is generated for each DS3 data subframe and contains either a valid data bit or a garbage data bit, as indicated by a stuff flag contained in the stuff word, to compensate for the difference in input and output data rates from the stuff FIFO. The DS3 master frame generated by a multiplexer from the video data and the other data channels is transmitted and decoded at the receiving end in a reverse manner.

Inventors

  • 👤 James A. Michener

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 19:47
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/16; H04J3/1605; H04J3/02; H04J3/06; H04J3/07; H04N; H04N7/00; H04N7/24; H04N7/52; H04N7/54

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 149 words
A video coder comprising: means for storing digital data at a first data rate and for reading out the digital data at a second data rate, the first and second data rates being asynchronous with respect to each other; means for coding a stuff word for addition to the storing means at a third data rate synchronous with the second data rate, the stuff word containing a valid digital data bit from the digital data when necessary to compensate for the rate differential between the first and second data rates; and means for multiplexing the digital data and the stuff word from the storing means with a plurality of other data channels having fourth data rates, the combination of the digital data, the stuff word and other data channels being in the form of a master digital data frame having a data rate equal to the second data rate.
Claim 2
Dependent Claim 149 words
A video coder comprising: means for storing digital data at a first data rate and for reading out the digital data at a second data rate, the first and second data rates being asynchronous with respect to each other; means for coding a stuff word for addition to the storing means at a third data rate synchronous with the second data rate, the stuff word containing a valid digital data bit from the digital data when necessary to compensate for the rate differential between the first and second data rates; and means for multiplexing the digital data and the stuff word from the storing means with a plurality of other data channels having fourth data rates, the combination of the digital data, the stuff word and other data channels being in the form of a master digital data frame having a data rate equal to the second data rate.
Claim 3
Dependent Claim 46 words
A video coder as recited in claim 1 wherein the master digital data frame comprises a plurality of subframes, each subframe having data bits representing digital data sampled at the first data rate, having the stuff word, and having data bits representing the other data channels.
Claim 4
Dependent Claim 26 words
A video coder as recited in claim 2 wherein the stuff word further comprises a digital bit from an ancillary source at a fifth data rate.
Claim 5
Dependent Claim 160 words
A video decoder comprising: means for demultiplexing digital data, a stuff word and a plurality of other data channels having first data rates from a master digital data frame having a second data rate, the master digital data frame being a combination of the digital data, the stuff word and the other data channels; means for storing the digital data and the stuff word at the second data rate and for reading out the digital data at a third data rate, the second and third data rates being asynchronous with respect to each other; and means for decoding the stuff word, the stuff word occurring at a fourth data rate synchronous with the second data rate and containing a valid digital data bit of the digital data when necessary to compensate for the rate differential between the second and third data rates, the valid digital data bit being read out of the storing means as part of the digital data.
Claim 6
Dependent Claim 160 words
A video decoder comprising: means for demultiplexing digital data, a stuff word and a plurality of other data channels having first data rates from a master digital data frame having a second data rate, the master digital data frame being a combination of the digital data, the stuff word and the other data channels; means for storing the digital data and the stuff word at the second data rate and for reading out the digital data at a third data rate, the second and third data rates being asynchronous with respect to each other; and means for decoding the stuff word, the stuff word occurring at a fourth data rate synchronous with the second data rate and containing a valid digital data bit of the digital data when necessary to compensate for the rate differential between the second and third data rates, the valid digital data bit being read out of the storing means as part of the digital data.
Claim 7
Dependent Claim 46 words
A video decoder as recited in claim 4 wherein the master digital data frame comprises a plurality of subframes, each subframe having data bits representing digital data sampled at the third data rate, including the stuff word, and having data bits representing the other data channels.
Claim 8
Dependent Claim 26 words
A video decoder as recited in claim 5 wherein the stuff word further comprises a digital bit from an ancillary source at a fifth data rate.
Claim 9
Dependent Claim 146 words
A video coder comprising: means for sampling a video input signal at a first data rate, the sampled video input signal being stored in a FIFO buffer; means for reading out the sampled video input signal from the FIFO buffer at a second data rate faster than and asynchronous with the first data rate; means for inserting a stuff word word into the sampled video input signal to compensate for the difference in rates between the first and second data rates, the stuff word containing a valid data bit when necessary to provide the compensation; and means for multiplexing the sampled video input signal, including the stuff word, with a plurality of other data channels that have third data rates slower than the first data rate and synchronous with the second data rate to produce a master data frame for transmission at the second data rate.
Claim 10
Dependent Claim 146 words
A video coder comprising: means for sampling a video input signal at a first data rate, the sampled video input signal being stored in a FIFO buffer; means for reading out the sampled video input signal from the FIFO buffer at a second data rate faster than and asynchronous with the first data rate; means for inserting a stuff word word into the sampled video input signal to compensate for the difference in rates between the first and second data rates, the stuff word containing a valid data bit when necessary to provide the compensation; and means for multiplexing the sampled video input signal, including the stuff word, with a plurality of other data channels that have third data rates slower than the first data rate and synchronous with the second data rate to produce a master data frame for transmission at the second data rate.
Claim 11
Dependent Claim 28 words
A video coder as recited in claim 7 further comprising means for inserting a digital bit from an ancillary source at a fourth rate into each stuff word.
Claim 12
Dependent Claim 155 words
A video decoder comprising: means for demultiplexing a master data frame transmitted at a first data rate into a video data channel and a plurality of other data channels; means for storing the data from the master data frame representing video data for the video data channel in a FIFO buffer at the first data rate, the stored data including a stuff word; means for reading out the stored data for the video data channel from the storing means, except the stuff word, at a second data rate slower than and asynchronous with the first data rate; and means for extracting from the stuff word a valid video data bit to compensate for the difference in rates between the first and second data rates when such compensation is necessary, the valid video data bit being added to the stored data for the video data channel from the storing means to produce an output video signal.
Claim 13
Dependent Claim 155 words
A video decoder comprising: means for demultiplexing a master data frame transmitted at a first data rate into a video data channel and a plurality of other data channels; means for storing the data from the master data frame representing video data for the video data channel in a FIFO buffer at the first data rate, the stored data including a stuff word; means for reading out the stored data for the video data channel from the storing means, except the stuff word, at a second data rate slower than and asynchronous with the first data rate; and means for extracting from the stuff word a valid video data bit to compensate for the difference in rates between the first and second data rates when such compensation is necessary, the valid video data bit being added to the stored data for the video data channel from the storing means to produce an output video signal.
Claim 14
Dependent Claim 33 words
A video decoder as recited in claim 9 further comprising means for extracting a digital bit from each stuff word corresponding to digital data at a third data rate for an ancillary device.

References Cited (Backward Citations)

US4538286A Cited
US4553129A Cited
US4558445A Cited
US4661966A Cited
US4649536A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-12-18 1993-06-19 1993-12-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-12-18 1997-06-19 1997-12-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-12-18 2001-06-19 2001-12-19 $7700.00 Window Closed / Lapsed

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