Abstract: Response fidelity problems appear for some specific video levels at PDP borders. The reason is that some cells at the border of the PDP panel are not completely closed and pollute when switched ON neighbouring cells being OFF. Therefore, it is suggested to encode the video levels in the border area in a specific way. Especially, for critical sub-fields within the code it is forbidden to insert a binary 0 between two binary 1. Thus, the neighbourhood of critical sub-fields being ON and OFF is avoided. Preferably, the specific border coding is performed under the control of an average power management and codewords being not used are recreated by dithering.

Abstract: A display system including a plurality of display units shall be supervised as to its proper functioning as well as the right content to be displayed. Therefore, there is provided a display device and a corresponding method for monitoring the presentation of a video signal on a display screen having a plurality of screen drivers. A mark signal is added to the video signal and a mark (13) is displayed within a picture on the basis of the video signal including the mark signal. The mark is sensed by a specific sensor and a corresponding sensing signal is provided. In order to supervise the functioning of each screendriver a specific mark signal is added for each screendriver into the video signal. Each of the plurality of marks is sensed and specific sensing signals are provided for each of the plurality of marks.

Abstract: For improving the grey scale portrayal, several dithering methods are used: Cell-based dithering, multi-mask dithering or error diffusion. Each of them has specific disadvantages. A simple combination of them does not bring expected advantages. However, an improvement is obtained if the result of the multi-mask dithering is used for controlling the error diffusion by a switch, for example.

Abstract: The invention relates to a method for processing video data to be displayed on a display device having a plurality of luminous elements corresponding to the pixels of a video picture, wherein an error diffusion step is applied to at least a part of said video data to refine the grey scale portrayal of said video picture, said error diffusion step comprising, for each current pixel of said part of video picture, a step of truncating the value of the corresponding video data and a step of diffusing the truncation error to at least one neighboring pixel. According to the invention, a noise is inserted on the error before and/or after its diffusion to the neighbouring cells. Owing to this principle no static pattern should be visible, improving the overall picture quality.

Abstract: CMOS image sensors are usually suffering from fixed pattern noise and random defect pixels. However, for economical reasons and in order to increase the manufacturing yield, some random defective pixels are usually accepted even for professional devices. In this case, the defect pixels are usually corrected by signal processing.

Abstract: The present invention relates to an apparatus for displaying an input picture of a sequence of input pictures during a video frame made up of N consecutive sub-frames, with N?2, comprising an active matrix comprising a plurality of light emitting cells, encoding means for encoding the video data of each pixel of the input picture to be displayed and delivering N sub-frame data, each sub-frame data being displayed during a sub-frame, a driving unit for selecting row by row the cells of said active matrix and converting, sub-frame by sub-frame, the sub-frame data delivered by said encoding means into signals to be applied to the selected cells of the matrix. According to the invention, at least one of the N sub-frame data generated for a pixel is different from the video data of said pixel.

Abstract: In the field of video displaying the low video levels do not generate large area flicker. For displaying video sources with higher frame rate, it is therefore the idea of the invention, to extract from two corresponding pixels of two successive video frames a common portion (Vx) that will be displayed at a sub-frequency fv/2 while the individual portions (V1?, V2?) of the corresponding pixels video are displayed at the correct high frequency fv. The time period for displaying two frames is divided into three sub-groups. Two groups of sub-fields with similar sizes, for displaying the individual portions (V1?, V2?) and one group of sub-fields, called extra-codes, for displaying the common portion (Vx). This enables to eliminate large area flicker artifacts from PDPs, when displaying 50 Hz based video norms by using upconverted 100 Hz video sequences and to display real high frequency video on the PDP (ca. up to 120 Hz) without frame dropping.

Abstract: The invention relates to a method for processing video pictures data for display on a display device having a plurality of luminous elements corresponding to the pixels of a video picture. The invention is related to every kind of display devices based on the principle of duty cycle modulation (pulse width modulation) of light emission and comprising a data driver. The aim of this method is to reduce the data driver overheating by optimizing the dithering of the pixel values of the video pictures. According to the invention, the pixel values used for dithering are chosen for reducing the state changes between successive bits of subfield code words of adjacent luminous elements.

Abstract: In many cases it is not possible to reproduce enough video levels on a PDP due to timing issues or a specific solution against the false contour effect. In such cases dithering is used to render all required levels. In order to reduce the visibility of the dithering noise there is performed a common change of the sub-field organization together with a modification of the input video data through an appropriate transformation curve based on the human visual system luminance sensitivity (Weber-Fechner law).

Abstract: Since the phosphor lag effect results from the slowness of the green and red phosphors and since it is not possible to make these phosphors faster, the blue one has to be made slower in order to reduce the color trail effect. Therefore, a part of the blue component is artificially delayed. Only a certain percentage of the blue component of the actual frame is transmitted during the actual frame, whereas the rest of the blue component will be transmitted during the next frames. The dynamic false contour effect introduced by this video processing may be compensated by subfield shifting.

Abstract: The picture quality on a plasma display panel shall be improved when the contrast and/or the brightness are reduced. This is achieved by estimating the reduction of the dynamic occurring in the front-end of the data processing of the plasma display device and by compensating it in the back-end. Specifically, the gain and/or offset of the video input data are adjusted and the power level of the adjusted video data is measured. The resulting power level information is updated on the basis of an attenuation information. The updated power level is used for the power management and the level of the video data being reduced in the front-end is increased on the basis of the attenuation information. Thus, the dynamic of the video and, as a result, the picture quality are improved.

Abstract: A subject of the invention is to ensure that a remote display device is only useable for a specific application like advertising or public information. According to the invention, this object is solved by a method for distributing display information to a remote display device, comprising the steps of: providing the remote display device with a signal comprising an activation key and the display information, providing the control unit of the remote display device with a locking function using a control key, and comparing the activation key to the control key and authorizing the displaying of the display information by deactivating the locking function if the activation key is fitting with the control key.

Abstract: The invention relates to a method and a device for encoding the video level of a pixel of a picture into a subfield code word in a display device. It can be applied to every display device using a PWM (Pulse Width Modulation) technology and subfields for displaying video picture. The bits of the subfield code word are computed recursively one after the other from the bit having the most significant weight to the bit having the least significant weight. According to the invention, for determining the state of a bit of the subfield code word, a first threshold and a second threshold is associated with said bit, said second threshold being greater than said first threshold, and the video level to be encoded by this bit and its following bits in the subfield code word are compared to the first and second thresholds. If the video level is lower than the first threshold, a state “OFF” is allocated to the bit.

Abstract: The sharpness impression when displaying a movement on an AMOLED (Active Matrix Organic Light Emitting Display) shall be improved. For this purpose, an apparatus for driving a cell of an AMOLED is provided including driving means for applying a driving voltage to the cell and for applying a luminance control signal to the cell during a pregiven time frame. The apparatus further includes controlling means for varying the driving voltage within the time frame according to a predefined function of time. For example, the driving voltage may be varied in the form of a triangle so that the lighting time over the frame is reduced while a CRT like behavior is emulated.

Abstract: The present invention concerns a method for transcoding a N bits word into a M bits word with M<N. The invention is applicable in various fields and more particularly in the display field. The method comprises the following steps:-breaking down the N bits word into an exponent part and a mantissa part having each a size which varies according to the value of said N bits word, the size of the mantissa part increasing with the value of said N bits word, and -encoding the exponent part of the N bits word into a variable number of bits A and removing, if need be, least significant bits of the mantissa part in order to obtain a mantissa with a variable number of bits B, with A+B=M.

Abstract: An imager achieves a desired image resolution by successively reproducing partial images which complement each other. The imager assigns pixels from an input image to the respective partial images according to complementing patterns that correspond to the pixel pattern of the imager. The imager reproduces the complementing pattern at different spatial positions, such that the complementing patterns merge. In order to avoid perceived double imaging of moving object s the image signal provided to the imager is assembled from an original image and a motion compensated interpolated image, which is derived from at least two consecutive images. Accordingly, every other partial image that is reproduced is derived from an interpolated image and takes into account movement of objects in the image that takes place between two consecutive images. In one embodiment the partial images are re-combined into one full image in a sequence that anticipates the distribution of the pixels used in the imaging device.

Abstract: The invention relates to a method for processing video pictures for display on a display device having a plurality of luminous elements corresponding to the pixels of a picture wherein the time of a video frame or field is divided into a plurality of N sub-fields during which the luminous elements can be activated for light emission in small pulses corresponding to a sub-field code word of n bits used for coding the p possible video levels lighting a pixel, comprising the steps of: determining if pictures are static pictures or moving pictures, in case of static pictures, processing video pictures using a first sub-field encoding method adapted to pictures when no motion is detected, and in case of moving pictures, processing video pictures using a second encoding method reducing dynamic false contour effect adapted to pictures when motion is detected. The invention applies to plasma display panels.

Abstract: The present invention relates to a new method for generating motion compensated picture by interpolating two consecutive source pictures without using motion estimator. For a given pixel to be interpolated, all displacements within a given search range between former and next frame are considered and for each displacement the displaced block difference is calculated. The pixel value is then equal to the sum of each averaged pixel pair within the search range weighted by a correlation coefficient function of the corresponding displaced block difference.

Abstract: The invention relates to a method for processing video pictures, the video pictures consisting of pixels digitally coded, the digital code word determining the length of the time period during which the corresponding pixel of a display is activated, wherein to each bit of a digital code word a certain activation duration called sub-field is assigned, the sum of the duration of the sub-fields according to a given code word determining the length of the time period during which the corresponding pixel is activated, said method comprising the following steps: detecting the video pictures source mode and the parity between pictures, if the source is in film mode, distributing the total number of sub-fields used for two frame raster in three groups of sub-fields and assigning to a value of a pixel a code word that corresponds to the distribution of the active sub-fields period over the three sub-fields groups, and if the source is in camera mode, distributing the total number of sub-fields used for each frame rast

Abstract: The present invention relates to a method for processing data of a picture to be displayed on a display panel with persistent luminous elements in order to reduce load effect in said display means. The method comprises the following steps: computing, for each subfield, the amount of activated luminous elements in each line of luminous elements of the display panel, called line load, calculating, for each subfield, the maximal difference of line loads of two consecutive lines of the display panel, and selecting, for each subfield, a sustain frequency in accordance with its maximal load difference in order to reduce line load effect.