Pulse or digital communications – Bandwidth reduction or expansion – Television or motion video signal
Reexamination Certificate
1999-11-26
2004-05-18
Kelley, Chris (Department: 2713)
Pulse or digital communications
Bandwidth reduction or expansion
Television or motion video signal
C375S240120
Reexamination Certificate
active
06738422
ABSTRACT:
The invention relates to an apparatus for the generation of a video signal of a quality corresponding to a generating bit rate x.
With such apparatuses, video signals are produced which are composed, for example, of a plurality of sequential image signals which directly follow one another time-wise, with Fe individual image signals being recorded at different geographical locations in order to be transmitted with the smallest possible time delay. This principle as, for example, used in order to put together live weather information from various geographical locations, with the corresponding video signal consisting of cyclically alternating image signals which are respectively recorded at different geographical locations by means of a camera. These image signals are then cut together in a transmission center in order to obtain the video signal that is to be generated in this manner. In accordance with the known principle, the transmission of the image sequences to the transmitting center takes place at least over part of the path by directional radio, cable or satellite. The image signals received from the transmitting center are in this case broadcast at once, i.e. live, as individual part segments of the generated video signal.
The known principle has the disadvantage that when using a directional radio transmission path only relatively short distances between the camera and the transmitting center can be bridged at reasonable cost. This disadvantage can indeed by overcome by the use of a cable or satellite transmission. However, the costs associated therewith are very high, so that, for example, the transmission of image signals from different locations of the earth to a unitary transmission center is not possible with economically sensible cost and complexity.
An object of the invention is to make available an apparatus of the initially named kind which makes it possible, at reasonable economic cost, to receive image signals recorded at different locations far apart from one another and to broadcast them as close as possible time-wise, i.e. with the least possible delay, as elements of a video signal.
In accordance with the invention this object is satisfied by an apparatus for the generation of a video signal of a quality corresponding to a generating bit rate x comprising
a receiver stage having a plurality n of receiving inputs for the simultaneous reception of different image signals Y
i
, at least one of which has a receiving bit rate y
i
lower than the generating bit rate x,
a storage stage for the intermediate storage of the received image signals Y
i
, and
a data retrieval stage for the reading out of the intermediately stored image signals Y
i
which takes place with the generating bit rate x and for the generation of the video signal which is composed of successive time segments of the different image signals Y
i
.
Thus, in accordance with the invention, the speed of transmission with which at least one and preferably a plurality or all image signals are received is smaller than the transmission speed with which the video signal composed of the image signals is transmitted. In order to enable the continuous transmission of the video signal, at high quality or at high transmission speed, despite this speed difference, a plurality of the individual image signals are in each case received simultaneously by the apparatus of the invention, with—as mentioned—the transmission speed of at least one of the received image signals being smaller than the speed of transmission of the video signal composed of the image signals. The reception of the image signals thus preferably takes place offset with time overlap, which will be explained further in the context of the description of the drawings.
An advantage of the apparatus of the invention is consequently to be seen in the fact that the transmission of the different image signals from image signal sources at different geographical locations to an apparatus in accordance with the invention used as a transmission center can take place at a lower data rate. As a result of the reduced speed of transmission already existing transmission paths or data lines with a comparatively low capacity, which are not normally suitable for the transmission of video signals can be used, which enables an image signal transmission over very large distances at comparatively low costs. The construction of new networks and transmission paths is thus not absolutely essential. In particular it is possible, in accordance with the invention, to return to existing selection line networks, such as telephone networks or Internet, in which an intentional dialing in and out can take place, which in turn has the consequence that a line is only used, and only has to be paid for, during those time intervals in which it is actually required.
Despite the slow transmission, it is possible to endow the generated video signal with a live character in accordance with the invention in that one ensures that an image signal fully received by the center at low speed is transmitted directly after, or with only a small time delay after, full reception as an element of the video signal. If the video signal consists exclusively of time segments, which only have a duration of a few minutes or less, then it can be ensured with the apparatus of the invention that the image signals received from the center are transmitted, only a few minutes after their recording by the image signal sources, as a component of the video signal. When producing a video signal which is, for example, intended to transmit weather information from different locations, a delay of this kind of a few minutes is straightforwardly acceptable, since this delay does not negatively impair the live character of the video signal in any way.
At this point it should be noted that the terms video signal and image signal which are used for the explanation of the invention basically also include such signals as additionally contain sound and/or text information in addition to the image or video information.
It is preferably the case, when so many receiving inputs are made available, that the sum of the reception bit rates of the simultaneously received image signals is greater than or the same as the generating bit rate x. In this way it is ensured that adequate image signals are always available for the production of a continuous video signal of high quality.
Receiving bit rates which differ from one another can be associated with different receiving inputs, for example, if more powerful lines exist for specific image signal sources or geographical locations than for other image signal sources.
It is also possible to make available at least one additional receiving input which can, for example, come into use when disturbances occur in the system, i.e. in the image signal sources, on the transmission paths and/or in the center. In the case of such disturbances an additional receiving input can, for example, be operated with an increased reception bit rate, in particular with the generating bit rate x, in order in this manner to receive a signal which can be transmitted directly—without intermediate storage and without time delay—as a video signal, so long as the disturbance in the system has not been remedied. It is particularly preferred when the additional receiving input is coupled via a dedicated line to an image signal source, so that when required a changeover can be made at any time to the image signal received via the additional receiving input at short notice.
In the receiving stage a plurality of receiving inputs can be switched together to a group for the reception of an individual image signal. A group of this kind can include two or more receiving inputs, and in an extreme case all the available receiving inputs. The data of an individual image signal can then be transmitted in parallel via such a group, which leads to a more rapid transmission of the image signal in comparison to the use of a single receiving input for an image signal.
It is particularly preferred when the numbers of the receiving inp
Earth View Television & Datatransfer GmbH
Fitch Even Tabin & Flannery
Kelley Chris
Wong Allen
LandOfFree
Video signal multiplexation apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Video signal multiplexation apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Video signal multiplexation apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3270682