Memory read/write organization for a television signal processor

• US 4,109,276 A
• Filed: 12/30/1976
• Issued: 08/22/1978
• Est. Priority Date: 03/19/1976
• Status: Expired due to Term

• Current Assignee: RCA Corporation (General Electric Company)
• Original Assignee: RCA Corporation (General Electric Company)
• Inventors: Dischert, Robert Adams, Banks, Arthur James, Hopkins, Robert Sherman Jr.
• Primary Examiner(s): Martin, John C.
• Application Number:
  US05/755,949
• Time in Patent Office: 600 Days
• Field of Search: 358/4, 358/8, 358/22, 358/17, 358/19, 358/149, 360/10, 360/11, 360/32, 360/33, 360/35, 360/36, 360/38
• US Class Current: 348/498
• CPC Class Codes: H04N 5/0736 using digital storage buffer techniques

Abstract

In a television signal synchronizer having a coherent memory, it is necessary to modify the writing of data into memory or the reading of data out of memory in order to provide field conversion. In the described apparatus, the reading out of data is always done according to a non-variant sequence determined by the local (studio) reference timing signals. In a first embodiment the read address generator signals are modified so as to read out the stored video signal in accordance with the non-variant write in sequence. In a second embodiment the write address generator signals are modified so as to position the incoming video signal into memory so that it is located in the proper memory position for the non-variant read out sequence.

Claims

1. Television signal synchronizer apparatus for providing field conversions between an input video signal and an output video signal, said input and output video signals being non-synchronous, comprising:

input and output video processing means adapted to be coupled to memory storage means;

a source of independent reference signals having a non-variant field sequence;

memory control means including memory input means for writing said input video signal into said memory storage means and memory output means for reading said output video signal out of said memory storage means;

means for developing field identification signals from one of said input video signal or said independent reference signal;

means for developing a source of field conversion signals from said field identification signals and said non-variant field sequence signal, and

delay means coupled to said memory input and said memory output means responsive to said source of field conversion signals and said field identification signals for modifying the writing and reading of data in and out of said memory storage means so as to provide field conversions consistent with said non-variant field sequence.

2. A television signal synchronizer in which incoming video signals are written into memory storage means, said incoming video signals comprising one or more television fields, each of said television fields comprising horizontal line signals having a horizontal blanking interval containing horizontal and burst synchronizing signal components and an active image information portion, said burst signal component being opposite in phase from one of said television fields to another, said television fields being subject to conversion on reading out of said memory storage means, comprising:

coherent memory storage means having preassigned fixed burst phasing for each line store of said memory storage means;

first signal processing means for developing a first composite horizontal sync and burst timing control signal indicative of the timing of said incoming video signal;

first delay means responsive to said first control signal for delaying the writing into memory of only said active video image information portions so as to write said video image information portion into said memory storage means consistent with said preassigned fixed burst phasing for each of said television fields;

means for generating a non-variant field write in sequence;

second signal processing means for developing a second composite horizontal sync and burst timing control signal indicative of the timing of said non-variant field sequence; and

second delay means responsive to said second control signal for delaying the reading out of memory of only said active video image information portions so as to read said video image information portion of each of said television fields out of said memory storage consistent with said non-variant field write-in sequence.

3. A television signal synchronizer in which incoming video signals are written into memory storage means, said incoming video signals comprising one or more television fields, each of said television fields comprising horizontal line signals having a horizontal blanking interval containing horizontal and burst synchronizing signal components and an active image information portion, said burst signal component being opposite in phase from one of said television fields to another, said television fields being subject to conversion on reading out of said memory storage means comprising:

coherent memory storage means having preassigned fixed burst phasing for each line store of said memory storage means;

means for generating a non-variant field read out sequence

first signal processing means for developing a first composite horizontal sync and burst timing control signal indicative of the timing of said non-variant field sequence;

first delay means responsive to said first control signal for delaying the reading out of memory of only said active video image information portions so as to read said video image information portion of each of said fields out of said memory storage means consistent with said non-variant field read out sequence

second signal processing means for developing a second composite horizontal sync and burst timing control signal indicative of the timing of said incoming video signal and

second delay means responsive to said second control signal for delaying the writing-into memory of only said active video image information portions so as to write said video image information portion of each of said television fields into said memory storage consistent with said preassigned fixed burst phasing for each of said television fields and said non-variant field read out sequence.