Abstract: A display device comprises revolving coloured wheels, so as to generate a periodic coloured beam, and an imager which modulates the coloured beam as a function of a received video signal. The coloured beam (8) takes successively at each period a plurality of primary colours in synchronism with the images generated by the imager for each primary colour. By adjustment of the relative position of the coloured wheels, it is possible to modify the hue of the primary colours so as to best match them to the received video signal.

Abstract: The present invention relates to a device and a method for displaying images. To combat the copying of images by a camcorder in a cinema auditorium, modulating the luminance of the pixels of a pattern around the value to be displayed to a high frequency which makes the pattern invisible to the human eye but which generates artefacts on the sequence filmed by the camcorder is known. According to the invention, it is proposed to temporally modulate the pattern only in the fixed areas (background or indoor scenes) or, where appropriate, the areas with weak movements. Thus, rather than degrading the image in the areas with movement by applying to them the temporal modulation processing, a decision is taken not to temporally modulate the pattern in these critical areas.

Abstract: The present invention relates to a method of displaying a colour video image in a sequential colour display panel. The video frame is divided into a plurality of consecutive time segments each assigned to a given colour component, and the video level of the pixels of the image is displayed by modulating the display time of the corresponding cells. The invention aims to propose a display method that reduces the blurring effect without causing colour break-up. According to the invention, at least one reference time segment is defined in said plurality of time segments, and the image is displayed giving priority to lighting the cells during the reference time segment and the time segments closest to the reference time segment. Application to LCOS, OLED and DMD sequential colour display panels.

Abstract: The invention relates to a method and a device for scanning pixels in a sequence of images presenting a time recurrence. According to the invention, the order of scanning of the pixels in one and the same line is reversed from one frame to the next. Applicable to motion estimation.

Abstract: The invention corrects display faults due to the disparities between the phosphors of a display device. The correction is carried out by image processing. The invention provides a method for displaying a sequence of video images on a phosphor device comprising at least two types of phosphors together with the device comprising the means for implementing this method. The correction is carried out by computing an intermediate image between two successive images, then by displaying one of the two successive images on one type of phosphor and by simultaneously displaying the intermediate image on another type of phosphor.

Abstract: The present invention relates to an apparatus and a device for displaying images. It is known to inlay a pattern of watermark type into the sequence of images to be displayed so as to combat the copying of images by picture-taking. This inlaying consists in modulating the intensity of the pixels of the pattern about the value to be displayed at a high frequency which renders the pattern invisible to the human eye but which generates artefacts on the sequence filmed by the camcorder. This technique poses problems when the sequence of images to be displayed comprises scenes in motion. The pattern appears since the integration carried out by the eye at the moment of display of the images is not correct. According to the invention, it is proposed that the patterns to be inlayed be motion compensated.

Abstract: The present invention relates to a device for digital display of a video image using time-division modulation. This device is intended to display a video image during a video frame comprising a plurality of consecutive subfields distributed within at least two separate identical time segments. According to the invention, the pixels of the video image change state at most once during each time segment and the video image to be displayed is saved in the image memory in the form of information identifying, for each subfield, the pixels changing state.

Abstract: The invention provides a solution for reducing the bit rate of the image memory which stores the binary images displayed on a digital display device. At least one binary image 16c is stored per group of at least two pixels of like binary value. Means duplicate the pixels of the image stored per group of pixels during display on a digital display element.

Abstract: The present invention relates to a method of processing a video image sequence in a liquid crystal display panel and to a device for implementing this method. According to one embodiment of the invention, at least one motion-compensated image is generated for each group of m consecutive images of the sequence, m being greater or equal to 2, in order to obtain a group of n consecutive images, with n>m. Said group of n consecutive images replaces the group of m consecutive images into the sequence. Next, for each pixel having in a current image of the new sequence a current grey level and in the next image a different target grey level, an intercalary grey level is calculated which is higher or lower than said target grey level depending on whether said target grey level is respectively higher or lower than the current grey level of the pixel. Next, in the current image, the current grey level of the pixels is replaced with said calculated intercalary level.

Abstract: The present invention relates to a method for displaying a video image on a digital display device during a video frame comprising at least two distinct time segments for displaying a grey level. The cells of the device are able to take selectively an on state or an off state. The cells are able moreover to change state several times during a video frame. According to the invention, the cells change state at most once during each time segment of the video frame. The invention makes it possible to attenuate or suppress disturbances related to the temporal integration and to the sequential displaying of the R, G, B components of the video image.

Abstract: The invention relates to a method of displaying a sequence of video images on a plasma display panel comprising a plurality of elementary cells coloured by phosphors (blue, green, red). According to the invention, a movement vector corresponding to movement between two successive images is computed and then the subscans associated with at least one type of phosphor is displaced, the amplitude of the displacement depending on the amplitude of the movement vector and on the type of phosphor. This allows the effects of image afterglow to be corrected.

Abstract: The present invention relates to a method of displaying video images on a display device and especially on a plasma display panel. The frame for displaying a video image is divided into two subframes, both comprising approximately the same number of subscans. The subscans of the first subframe are arranged in a first order in which their weights increase and those of the second subframe in the reverse order. The second subframe is consecutive to the first subframe. Each cell of the PDP changes state at least once during the first subframe. The same applies during the second subframe.

Abstract: The present invention relates to a method of displaying video images on a digital display device. The display frame of an image comprises periods for addressing the odd row cells and the even row cells of the device separately and periods for erasing them separately. Each subfield of the video frame comprises at least one address period, one erase period and at least one sustain period. The periods are arranged among themselves so as to obtain an arrangement of the subfields in the video frame or a temporal position of the video frame which is different for the odd rows and the even rows of the device. Preferably, the device is a plasma display panel.

Abstract: The object of the invention is to provide a system for encoding grey levels which makes it possible to reduce the problems of contouring by increasing the number of subscans using subscans common to several rows, thereby remedying the error due to the difference between the grey levels of simultaneously scanned cells. The invention provides a method and a device which make row groupings dynamically according to the content of the image.

Abstract: The present invention relates to a method of displaying video images on a plasma display panel. The invention is applicable in plasma display panels (PDPs). According to the invention, in order to achieve contouring movement compensation, the subscans are divided into two symmetrical groups of subscans. Moreover, the movement of the video image to be displayed with respect to the preceding video image is estimated so as to generate a movement vector for each pixel of the video image. Finally, for each pixel of the video image, the subscans of the second group are displaced by an amount proportional to the estimated movement vector.

Abstract: The invention concerns a method for displaying video images on a plasma display panel. The invention is particularly applicable in plasma display panels comprising a matrix of elementary cells which can be either lighted or unlighted. The invention is characterized in that in order to provide motion compensation of irregular contours, the method consists in defining in the temporal integration window a reference time and in moving the underscans of the temporal integration window relative to said reference time. The underscans consecutive to the time reference in the temporal integration window are moved in the motion direction and the other underscans are moved in the opposite direction.

Abstract: The invention deals with the large area flicker effect reduction in display devices like plasma display panels, in which the light output is controlled by small pulses over a whole frame period and the amount of small pulses determine the brightness of the light output. The invention proposes an adaptation of the known principle of sub-field grouping for large area flicker reduction for the specific sub-field coding process called incremental sub-field coding, in which only those sub-field code words are taken for display driving having the characteristic that there is never a sub-field inactivated between two activated sub-fields or never a sub-field is activated between two inactivated sub-fields.

Abstract: The invention corrects display faults due to the disparities between the phosphors of a display device. The correction is carried out by image processing. The invention provides a method for displaying a sequence of video images on a phosphor device comprising at least two types of phosphors together with the device comprising the means for implementing this method. The correction is carried out by computing an intermediate image between two successive images, then by displaying one of the two successive images on one type of phosphor and by simultaneously displaying the intermediate image on another type of phosphor.

Abstract: The object of the invention is to provide a system for encoding grey levels which makes it possible to reduce the problems of contouring by increasing the number of subscans using subscans common to several rows, thereby remedying the error due to the difference between the grey levels of simultaneously scanned cells. The invention provides a method and a device which make row groupings dynamically according to the content of the image.