Sound-in-video television transmission

• US 4,156,253 A
• Filed: 02/03/1978
• Issued: 05/22/1979
• Est. Priority Date: 02/09/1977
• Status: Expired due to Term

• Current Assignee: Alcatel SA (Nokia Corporation)
• Original Assignee: International Standard Electric Corporation (ITT, Inc.)
• Inventors: Steudel, Gunter
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US05/875,260
• Time in Patent Office: 473 Days
• Field of Search: 358/12, 358/13, 358/143, 358/144, 358/145, 358/147
• US Class Current: 348/524
• CPC Class Codes: H04N 7/085 the inserted signal being digital

Abstract

A sound-in-video signal transmission system is made compatible with present domestic TV receivers by transmitting the color-sync signal in the time domain according to the current standard, and the sound signals are transmitted partly before it and partly after it.

Claims

1. A television transmission system wherein a color-sync signal and digital sound signals from at least one sound channel are transmitted in the horizontal blanking intervals during the period of the back porch, with the color-sync signal and the digital sound signals separated from each other, comprising:

transmitting means for transmitting part of the sound signals to be transmitted during a line period before the color-sync signal, and the remainder thereafter;

receiving means for receiving the video-sound signal so composed and extracting the sound signals therefrom.

2. A system according to claim 1, wherein the transmitting means and the receiving means include counters for reading the sound signals from, and writing them into, a buffer store which count the clock pulses for the buffer store and interrupt them for a time corresponding to the duration of the color-sync signal.

3. A system according to claim 1 wherein the receiving means are incorporated in domestic receivers.

4. A system according to claim 1 wherein the receiving means are designed as add-on units for domestic receivers.

5. A method for transmitting a color-sync signal and sound signals during the horizontal blanking interval of a video signal in a television system, comprising the steps of:

converting the sound signals into a digital form;

transmitting the color-sync signal during a predetermined time of the horizontal blanking interval;

transmitting a portion of the sound signals during a period before the color-sync signal; and

transmitting the remainder of the sound signals after the color-sync signal.

6. A method for transmitting as described in claim 5, additionally comprising the steps of:

generating and transmitting a starting pulse immediately prior to transmission of the first portion of the sound signals; and

generating and transmitting a control pulse after the last sound signal has been transmitted.

7. A system according to claim 5, wherein the method includes the additional steps of:

storing the digital sound signals;

reading a portion of the digital sound signals from storage during a predetermined portion of the horizontal blanking interval;

interrupting the reading of digital sound signals for a time period corresponding to the duration of the color-sync signal; and

reading the remainder of the digital sound signals from storage after the color-sync signal has been transmitted.

8. A method as described in claim 5, additionally comprising the steps of:

receiving the transmitted signals; and

separating the digital sound signals from the color-sync signal.

9. A method as described in claim 8, additionally comprising the steps of:

detecting the reception of the digital sound signals;

writing said digital sound signals into a storage means for a predetermined period of time;

interrupting said writing for a predetermined period of time corresponding to the duration of the color-sync signal;

writing the remainder of the digital sound signals into the storage means; and

reading the digital sound signals from the storage means.

10. A method of transmitting a sound-in-video television signal, comprising the steps of:

transmitting a color-sync signal during a predetermined standard time domain of a horizontal blanking interval; and

transmitting the sound signals during the horizontal blanking interval partially before the color-sync signal and partially after the color-sync signal.