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: 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, encoder 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 encoder 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: 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.

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 of estimating motion between two video frames. According to the invention, the motion estimation is done by using first one motion estimation in the horizontal direction and then one motion estimation in the vertical direction. Preferably, a plurality of motion estimations in the horizontal direction are used alternately with motion estimations in the vertical direction. It allows reducing the complexity of the estimation.

Abstract: Overheating while enabling a full flexibility in the display usage should be avoided. This object is solved by a method for avoiding the overheating of a driver circuit in a plasma display panel wherein the driver circuit receives serially display data in form of a sequence of sub-field data bits and forwards parallelly the display data in the form of data blocks each consisting of a predefined number of sub-field data bits, the method comprising the steps of counting sub-field data bits the value of which differs from that of a neighboring or preceding sub-field data bit and providing a respective counting signal indicative of heat contributions of sub-field data bits and, if said counting signal is above a pregiven threshold, taking countermeasures for reducing said temperature.

Abstract: The invention concerns a video processing for improving the picture quality of picture which are displayed on display devices like plasma display panels and all kind of display devices based on the principle of duty cycle modulation of light emission and for reducing the average power dissipation. The basic idea behind the invention is to generate only the required amount of sustain pulses that effectively produce light and to avoid generating unnecessary sustain pulses. To this end, the video range of the input video is increased in order to be equal to a nominal range, 255 in the case of a 8-bit coding, and a power level mode with a reduced number of sustain pulses is selected to keep constant the brightness of the image. The number of sustain pulses that do not produce light is reduced.

Abstract: The invention relates to a method for processing a stereoscopic image, said stereoscopic image comprising a first image and a second image comprising at least one first black band. In order to reduce the display errors linked to black bands, the method comprises steps for: estimation of at least one first parameter representative of said at least one first black band, generation of a third image from said stereoscopic image by disparity compensated interpolation, said third image comprising at least one second black band, at least one second parameter representative of said at least one black band being a function of at least one first parameter. The invention also relates to a corresponding stereoscopic image processing module and a display device comprising the processing module.

Abstract: The gravity centered coding shall be improved with respect to false contour effect disturbances on plasma display panels for example. Therefore, there is provided a GCC code (gravity center coding) and a motion amplitude of a picture or a part of a picture. Furthermore, there is provided at least one sub-set code of the GCC code. The video data are coded with the GCC code or the at least one sub-set code depending on the motion amplitude. Thus, it is possible to reduce the number of coding levels if the motion increases. A further improvement can be obtained by using texture information for selecting the GCC code.

Abstract: 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 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. In determining the state of a bit of the subfield code word, a first threshold and a second threshold is associated with the bit, the second threshold being greater than the 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. A state is allocated to the bit based on the comparison.

Abstract: A picture quality when reducing the brightness or the contrast of the picture on a plasma panel shall be improved. For this purpose there is provided a driving apparatus including brightness/contrast control means for receiving video input data for modifying the video levels of the video input data in accordance with external adjustment data and for outputting modified video data. First power measurement means measure a power level of the modified video data and supply a first power level. Second power measurement means measure a power level of the video input data and supply a second power level. Generator means generate a third power level comprised between the first power level and the second power level or equal to the larger one to data processing means. The data processing means calculate the maximum number of sustain pulses per frame applicable to the modified video data on the basis of the third power level and control the display of the modified video data on the plasma display panel.

Abstract: An addressing method for sample and hold displays suitable for multi-scan applications (supporting several frame rates) shall be provided. Thus, there is disclosed a method for displaying a picture on a display screen including the steps of providing an input signal including a sequence of plural frames, each corresponding to a single picture, temporally dividing each frame having a frame duration into sub-fields and controlling a display element of the display screen on the basis of the sub-fields. The number and/or duration of sub-fields of each frame is automatically adapted to the frame duration of the frame. Furthermore, the amplitude of a sub-field controlling signal corresponding to the last subfield of each frame may be automatically adapted to the frame duration of the frame. Such display methods provide for a high grayscale quality and linearity even if the frame rate is not stable nor well-defined.

Abstract: The invention relates to a method for power level control of a display device and an apparatus for carrying out the method. Classically, a power level mode defining a subfield organization to be used for subfield coding is selected as a function of the average power level of the picture to be displayed for keeping constant the power consumption of the display device. According to the invention, it is proposed to select the power level mode as a function of the input frame frequency in such a way as to have as little as possible deviations from nominal peak white and full white values at the same time that an overloading of the panel power supply is prevented. More particularly, the number of sustain pulses within the video frame and selected by the power level mode is modified as a function of the input frame frequency.

Abstract: The invention relates to a new method for power level control of a display device and an apparatus for carrying out the method. Classically, the contrast/brightness control and the power management (based on an average power level control) are made independently. These two controls can be contradictory. According to the invention, the power level mode and more particularly the number of sustain pulses within the video frame is selected as a function of the average power level (APL) of the picture to be displayed and the picture control signal representing the desired contrast and/or brightness value.

Abstract: A method for processing video data for display on a display device having a plurality of luminous elements comprising: applying a dithering function based on single ones of said luminous elements to at least part of said video data to refine the grey scale portrayal of video pictures of said video data, computing at least one motion vector from said video data, and changing at least one of the phase, amplitude, spatial resolution and temporal resolution of said dithering function in accordance with said at least one motion vector when applying the dithering function to said video data.

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 r

Abstract: Method and apparatus for reducing driver energy consumption of drivers of a display device each supplied by an input codeword as e.g. for data drivers of a plasma display panel supplied by sequences of subfield data bits in form of a codeword comprising a predetermined number of bits are recommended, wherein the apparatus comprises a driver transition energy limitation circuit for toggling bits of the input codeword applied to the driver transition energy limitation circuit and providing a codeword reducing the driver energy consumption. A toggle map, which is generated from a combination of a transition map determining a bit in the input codeword if toggled reduces energy consumption and a flag map determining a number of least significant bits exceeding a cell energy limit value, is applied to an input codeword for the driver to toggle bits of said input codeword for reducing driver energy consumption without a perceivable image quality degradation.

Abstract: The invention relates to a method of estimating motion between two video frames. According to the invention, the motion estimation is done by using first one motion estimation in the horizontal direction and then one motion estimation in the vertical direction. Preferably, a plurality of motion estimations in the horizontal direction are used alternately with motion estimations in the vertical direction. It allows reducing the complexity of the estimation.

Abstract: Luminous elements of the three colours red, green and blue of video display devices have a different response time. Therefore, a coloured edge and trail appear at edges in direction of a moving object. In order to reduce the disturbing character of such coloured edges and trails, a horizontal spatial equalisation of the response time of luminous elements having a shorter response time by low-pass filtering a component signal of the video component signals for driving luminous elements having a shorter response time dependent on a horizontal speed of changes of the component signal is recommended to reduce phosphor lag artifacts on display devices. The arrangement for processing video component signals of different colour comprises a compensation unit which according to a preferred embodiment is realised by a FIR filter and a horizontal speed correction unit supplied with a horizontal and vertical motion estimation signal.

Abstract: The invention relates to a method and a device for encoding the luminance value 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. It can be used to compensate for any luminance problem that can be estimated. The general idea of the recursive coding is to encode one sub-field after the other in order to be able to compensate for problems occurring on one sub-field with the other sub-fields. More particularly, the bits of a subfield code word are computed recursively one after the other such that the defects (e.g. line load and/or linearity) in the light emission or luminance generated by a bit of the subfield code word can be compensated by the following bits of the subfield code word.