North American Philips Corporation

North American Philips Consumer Electronics Corp.

Kenneth R Skinner

Joseph P Bingham

James E Hitchcock

An extended definition television (EDTV) system transmits, receives and displays both EDTV and conventional signals using a NTSC channel bandwidth. The system produces an EDTV broadcast signal having a picture with a 16:9 aspect ratio and at least one adjacent horizontal border to produce an overall image aspect ratio of 4:3. Picture information is also selectively modulated onto the horizontal border. The EDTV broadcast signal is transmitted in a standard television format, and a receiving circuit is provided comprising a display means with a 16:9 aspect ratio, a detector for determining whether an EDTV or other type of signal is being received, and an expansion circuit responsive to the detector means to produce an expanded picture for display. When an EDTV signal is received, it is expanded and filtered vertically and is expanded horizontally and the 16:9 picture is displayed on the 16:9 display. The receiving circuit derives picture information from both the picture portion and the border portion of the EDTV signal. When a conventional television signal is received, it is displayed on the 16:9 display means with at least one vertical border so that the picture has a 4:3 aspect ratio. The EDTV signal is also compatible with and may be received and displayed on standard NTSC receivers as a 16:9 picture with at least one horizontal border.

Compatible EDTV system providing multi-aspect ratio display on EDTV and

The contrast of a luminescent image produced by a CRT display device is improved by disposing a variable light transmissivity panel adjacent the CRT faceplate to intercept and attenuate ambient light reflected from the screen of the CRT. Control circuitry is provided to effect a decrease in the transmissivity of the panel in response to increasing ambient light intensity. The circuitry also effects an increase in the electron beam current with increasing ambient light intensity to increase the intensity of the luminescent image produced by the electron beam. When the device is not operating, the panel has a very low transmissivity causing the faceplate to appear dark.

CRT display device with variable light transmission panel

A complex television system is provided for accommodating at the same time both highly technically oriented and less technically oriented users of the system. The system includes a state of the art complex television, a complex remote control transmitter device for use by the technically oriented user in both programming and, if desired, controlling the television, and a simple auxiliary remote control transmitter device for the less technically oriented user. The simple auxiliary remote control transmitter device has a minimum of keys, such as power-on, channel-up, channel-down, volume-up, and volume-down, as well as a switch which identifies the user. Different power-on and channel-up and down codes for each switch position is provided by the simple auxiliary remote control transmitter device, and each such code is different than the corresponding codes of the complex remote control transmitter device. In this manner, a microprocessor in the television will recognize which user is in control. By using the complex remote control transmitter device, values for personal preference parameter and/or channel rings associated with each user may be entered and stored in a programmable memory of the television. Then, when the television recognizes the power-on code for a particular user, the personal preference parameter and/or channel rings are immediately accessed. In this manner, less technically oriented users may be the beneficiaries of complex personal preference rings programmed by them by a highly technically oriented user, and will only have to deal with a simple auxiliary remote control transmitter device to control the television.

Remote control television system using supplementary unit for simplified

An extended definition television (EDTV) system transmits, receives and displays both EDTV and NTSC signals using a NTSC channel bandwidth. The system procudes an EDTV broadcast signal having a picture with a 16:9 aspect ratio and at least one adjacent horizontal border to produce an overall image apsect ratio of 4:3. Picture information is also selectively modulated onto the horizontal border. The EDTV broadcast signal is transmitted in a NTSC format, and a receiving circuit is provided comprising a display with a 16:9 aspect ratio, a detector for determining whether an EDTV or other type of signal is being received, and an expansion circuit responsive to the detector to produce an expanded picture for display. When an EDTV signal is received, it is expanded and filtered vertically and is expanded horizontally and the 16:9 picture is displayed on the 16:9 display. The receiving circuit derives picture information from both the picture portion and the border portion of the EDTV signal. When an NTSC signal is received, it is displayed on the 16:9 display with at least one vertical border so that the NTSC picture has a 4:3 aspect ratio. The EDTV signal is also compatible with and may be received and displayed on standard NTSC receivers as a 16:9 picture with at least one horizontal border.

Single channel NTSC compatible EDTV system

A conventional peaking signal derived by delaying the incoming video or luminance signal first by one horizontal line delay and then by a second horizontal line delay is modified by multiplication with an adaptive factor. The adaptive factor is derived by first taking the difference between the incoming signal and the twice delayed signal, then deriving the magnitude or the square of this difference and multiplying this by a factor K empirically derived for the particular display device. The resultant signal is then subtracted from unity. This yields the factor by which the conventional peaking signal is multiplied. The conventional signal multiplied by this factor constitutes the final peaking signal which is added to the 1H delayed luminance signal to yield the desired peaked luminance signal.

Method and apparatus for generating an adaptive peaking signal

The edges of an incoming video signal are sharpened by switching the output furnishing the sharpened signal in sequence first to receive a signal delayed by a greater amount, i.e. a signal which has not as yet undergone transition, and, secondly, to receive a signal delayed by a lesser amount, i.e. one that has already completed the transition. The rise time of the affected edge thus depends only on the time required to switch from one terminal to the next. The same switching sequence is carried out regardless of whether the transition is a negative going or positive going transition.

Method and apparatus for improving the rise and fall time of a video

An interpolated line is created between the horizontal lines of each field of an interlaced television signal on a pixel-by-pixel basis. For each pixel to be interpolated, the pixel in the same field located immediately above and below the interpolated pixel are compared. If the difference between the two values exceeds a predetermined difference, the larger or the smaller pixel value is picked for the interpolated pixel, depending upon the value of the corresponding pixel in the immediately previous field. If the difference between the two pixel values is smaller than the reference value, either of the two values or an average of the two values may be used as the interpolated pixel value.

Growing community of inventors

Jefferson City, TN, United States of America

Kenneth R Skinner