Patents Assigned to Thomson Grand Public
  • Patent number: 5214751
    Abstract: A method enabling reconstitution of the luminance values of a frame from the luminance values of the pixels of two known frames. The method includes estimating a velocity vector for each pixel of a single frame corresponding with an instant T.sub.1 between T.sub.a and T.sub.b, or being T.sub.a or T.sub.b. For each pixel of this image, called the father pixel, the coordinates of the center of a pixel to be interpolated, called the son pixel, are successively determined, corresponding with the center of the father pixel by a translation whose vector is a function of the velocity vector of the father pixel, multiplied by the duration T.sub.1 -T.sub.j.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: May 25, 1993
    Assignee: Thomson Grand Public
    Inventor: Philippe Robert
  • Patent number: 5055833
    Abstract: A control method and control circuit for an electro-optic matrix screen wherein: a) during a frame time period, and during the control of certain lines, the screen is controlled by voltages of a determined polarity; b) during the same frame time period, and during the control of the other lines, the screen is controlled by voltages of reverse polarity; and c) during the following frame time period, the control voltages is reversed. An inverter control circuit C.INV enables the inversion of the voltages given by input circuits INV, IN, ADD.C to the column electrodes, and by an addressing circuit ADD.C to the line electrodes. The invention can be applied to the control of liquid crystal display panels to eliminate display faults.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: October 8, 1991
    Assignee: Thomson Grand Public
    Inventors: Robert Hehlen, deceased, by Philippe Hehlen, legal representative, by Bernard Hehlen, legal representative, Maurice Le Galguen, Bruno Mourey
  • Patent number: 4938567
    Abstract: The invention concerns an electro-optical panel and, more especially, an intersection point transistor structure made with thin films, wherein there is provided a doubling of the line and column electrodes (LG, CL) by doubling elements (1g.sub.1, Col. 1, Col. 2), as well as a light barrier (EC) shielding a transistor. The invention also concerns a method for making a screen of this type. The invention can be applied especially in the technology of liquid crystal display panels.
    Type: Grant
    Filed: July 20, 1988
    Date of Patent: July 3, 1990
    Assignee: Thomson Grand Public
    Inventor: Eric Chartier
  • Patent number: 4903128
    Abstract: Disclosed is a method for the reduction of the noise generated during the encoding/decoding of digitized images operating by blocks. To reduce the faults visible in the restored image, the method consists in filtering the image by using a filtering window, for example with dimensions of 3.times.3 pixels, which scans the image, the current point being the central point of this window, and in determining, for each point, the mean of the values associated wih the points of this window, and in determining for the current point, from this mean and from a characteristic value of the operating status of the encoder, a filtering parameter which can be used to determine the filtered value associated with the current point. The invention can be applied to the resutitution of block encoded images especially in digitalized video tape-recorders.
    Type: Grant
    Filed: August 25, 1988
    Date of Patent: February 20, 1990
    Assignee: Thomson Grand Public
    Inventor: Dominique Thoreau
  • Patent number: 4814862
    Abstract: The luminance and chrominance signals of a PAL or SECAM composite video signal are separated by means of a method comprising the following steps:sampling and digitizing the composite video signal;determination of a luminance signal and a chrominance signal by means of a first processing channel, from the digital sample of the current point of the image, from a previous sample corresponding to the current point located on the line in the previous field which is spatially positioned in the image immediately beneath the current line, from the luminance signal values already determined in a spatiotemporal neighborhood of the current point and in accordance with an analysis of the local spatiotemporal context of the current point;determination of a luminance signal and a chrominance signal by means of a second processing channel by applying the digital composite signal to the input respectively of a luminance filter and a chrominance filter;selection of the luminance and chrominance signals which are present at th
    Type: Grant
    Filed: December 28, 1987
    Date of Patent: March 21, 1989
    Assignee: Thomson Grand Public
    Inventor: Serge Travert
  • Patent number: 4754491
    Abstract: The invention provides cosine transform computing devices and image decoding devices and coding devices comprising such computing devices. One embodiment of a device for calculating monodimensional cosine transforms by blocks of 16 values comprises: three elementary computing devices for carrying out operations of the addition or subtraction type; two elementary computing devices for carrying out operations of the multiplication and accumulation type; a coupling device; and control means. The number of elementary computing devices is equal to the minimum number required for carrying out the transform calculations at the timing imposed by the arrival of the values to be transformed. Each elementary computing device is reused several times for the calculation of each transform. The coupling device is controlled by the control means for connecting the elementary computing devices in series in an order which varies at each step of the succession of calculations.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: June 28, 1988
    Assignee: Thomson Grand Public
    Inventors: Denis Mischler, Yves Le Pannerer
  • Patent number: 4707738
    Abstract: This process uses a bidirectional transformation by blocks for images representing highly animated scenes and also uses a differential coding of the transformation coefficients when the pictures show slightly animated scenes. The coding device mainly comprises a cosine transformation device, a subtractor, and inter-image decoding device, a multiplexer, a device for discriminating the blocks showing highly animated scenes and blocks showing slightly animated scenes. The latter device controls the multiplexer. The subtractor and the decoding device make it possible to calculate the difference between each transformation coefficient and the homologous coefficient of the homologous block in the preceding picture. Moreover, a weighting device makes it possible to transmit with a larger number of bits the coefficients or coefficient differences corresponding to the low spatial frequencies of the images.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: November 17, 1987
    Assignee: Thomson Grand Public
    Inventors: Alain Ferre, Yannick Villalon