US 4,521,803 A · System for compatible transmission of high-resolution TV

Abstract

A high-resolution television system is described which provides twice the vertical resolution of present television standards and is compatible therewith. A high-resolution television camera substantially simultaneously provides information from each of a pair of adjacent scan lines; the luminance information of both lines is added to provide information for amplitude modulation onto a luminance carrier, while the difference in luminance of the two adjacent scan lines is utilized to modulate a carrier phased in quadrature with the luminance carrier. The chrominance values of both lines are added to modulate a chrominance carrier. The bandwidth of the resulting luminance and chrominance signals are compatible with that of a carrier modulated by a single raster line. At a television receiver, a synchronous quadrature detector provides the sum and difference luminance signals, which are then respectively added to and subtracted from one another to obtain the adjacent line luminance signals for display upon a picture tube in a high-definition television set. A standard television set utilizes only the additive luminance signal to display a compatible picture. Increased horizontal definition, by increasing transmitted signal bandwidth or by utilization of horizontal interlace, and/or increased chroma definition, may be utilized alone or in conjunction with increased vertical resolution to provide a total high-resolution television picture.

Claims98

Dependent claims

A method for increasing the vertical luminance resolution capacity of a transmitted television signal, comprising the steps of:

(a) providing a television camera having a luminance video output signal of magnitude responsive to the visual luminance value at a raster spot then being scanned by a beam;
(b) scanning the beam through a plurality of lines in a horizontal direction;
(c) scanning the beam through each of a plurality L of different vertically-displaced lines during each of the plurality of horizontal line scans;
(d) generating a like plurality L of substantially simultaneous luminance signals each responsive to the luminance video output signal provided by the camera when the beam is at positions defined by the associated one of the plurality L of vertically-displaced lines;
and
(e) modulating a different characteristic of at least one luminance carrier with each of the plurality L of luminance signals to transmit the increased vertical luminance resolution capacity television signal.

3 more elements

A method for increasing the horizontal luminance resolution of a television signal, comprising the steps of:

generating a raster scan waveform having a standard number of horizontal and vertical scan lines in a display raster;
providing a camera having a luminance video output of magnitude responsive to the visual luminance value at a spot on said raster then being scanned by a beam responsive to said raster scan waveform;
providing the camera with a luminance video bandwidth greater than the normal video bandwidth utilized with a raster having the standard number of scan lines;
and
transmitting the luminance video output of said camera as a modulated carrier signal having a lower sideband of bandwidth greater than an upper sideband and with a total bandwidth substantially greater than the bandwidth normally utilized for transmitting a television signal having the normal scan line video signal.

2 more elements

A method for increasing the horizontal luminance resolution of a television signal, comprising the steps of:

providing a television camera having a high horizontal video resolution capability;
scanning a camera beam through a normal number of horizontal scan lines for a normal-resolution picture;
sampling the luminance values along each horizontal scan line at a sampling frequency causing an integer number I of substantially equally-spaced successive samples to occur for each pixel defined in a normal-resolution horizontal line;
selecting, for each successive one of a plurality I of frames, similarly placed samples in each successive group of samples each having the integer number I of samples therein;
forming each successive one of the integer number I of successive video frame waveforms from the successively selected sampled groups;
and transmitting the successive video frame waveforms to provide a television picture having the integer number I of frames interlaced to provide a picture also having increased horizontal resolution when displayed.

3 more elements

A method for increasing chroma resolution in a received color television signal, comprising the steps of:

recovering luminance information from the received television signal;
recovering chroma information from the received television signal;
extracting information characterizing the sharpness of luminance edges from the recovered luminance information;
and
modifying the recovered chroma information, responsive to the extracted luminance edge information, to increase the sharpness of chroma edges and provide a displayed color television signal having an increased color resolution relative to the color resolution of a picture displayed with unmodified color information.

2 more elements

Apparatus for transmitting a television signal with increased vertical resolution, comprising:

first means for providing a horizontal line scanning waveform;
second means for providing a vertical line scanning waveform;
at least one camera tube having at least one beam scanned to a raster position responsive to the vertical and horizontal line scanning waveforms for providing at least one video signal of amplitude responsive to the amount of light impinging upon the spot at which the associated camera beam is then positioned;
third means for providing another waveform combinable with said vertical line scanning waveform for causing each of the said at least one camera beam to scan at least consecutive portions of a plurality of vertically-displaced and non-overlapping lines during each horizontal scan;
and
a plurality of means each for sampling and holding the amplitude of the video waveform output from each of the at least one camera tube whenever said at least one beam is at a point defining an associated one of said plurality of vertically-displaced lines, each of said sampling and holding means providing one of a like plurality of sequential vertical line video waveforms for transmission.

3 more elements

Apparatus for transmitting a television signal with increased vertical resolution, comprising:

first means for providing a horizontal line scanning waveform at a frequency equal to an even-integer multiple of a normal horizontal scanning frequency;
second means for providing a vertical line scanning waveform;
third means for providing a square waveform at a frequency equal to one-half the horizontal line scanning frequency provided in said first means;
means for combining said vertical line scanning waveform and said another waveform to provide a vertical deflection waveform;
at least one camera tube having at least one beam scanned to a raster position responsive to the vertical deflection and horizontal line scanning waveforms for providing at least one video signal of amplitude responsive to the amount of light impinging upon the spot at which the associated camera beam is then positioned;
and
means for consecutively storing the video signals produced during scanning of a plurality of horizontal line scans and for simultaneously reading out another plurality of nonconsecutive stored video signals to provide a like plurality of video luminance waveforms for transmission.

4 more elements

Apparatus for increasing the horizontal luminance resolution of a television picture, comprising:

a television camera having a high horizontal resolution capability;
means for scanning a beam of the camera through a normal number of horizontal scan lines for a normal resolution picture;
means for sampling the luminescence values along each horizontal scan line of a sampling frequency causing an integer number I of substantially equally-spaced successive samples to recover each pixel defined in a normal-resolution-horizontal line;
means for selecting, for each successive one of a plurality I frames, similarly placed samples in each successive group of samples each having the integer number I of samples therein;
means for forming each successive one of the integer number I of successive video frame waveforms from the successively selected sample group;
and
means for sequentially transmitting the successive video frame waveforms, to provide a television signal representing a picture having the integer number I of frames interlaced to provide a picture increased horizontal resolution when displayed at a receiver.

4 more elements

Apparatus for increasing chroma resolution in a color television receiver, comprising:

means for recovering luminance information from a received television signal;
means for recovering chroma information from a received color television signal;
means for extracting information characterizing the sharpness of luminance edges from the recovered luminance information;
and
means for modifying the recovered chroma information, responsive to the extracted luminance edge information, to enhance the sharpness of chroma edges and increase color resolution in a color picture displayed, responsive to the modified chroma information and the recovered luminance information, relative to the color resolution of a picture displayed on the same device with unmodified color information.

2 more elements

Dependencies are inferred from the claim text.

System for compatible transmission of high-resolution TV

Life of this patent

System for compatible transmission of high-resolution TV

Life of this patent

Abstract

Claims98