公开(公告)号：EP1234298A1

公开(公告)日：2002-08-28

申请号：EP00964228.1

申请日：2000-09-23

申请人： Thomson Licensing S.A.

发明人： WEITBRUCH, Sébastien ,  ZWING, Rainer

IPC分类号： G09G3/28

CPC分类号： G09G3/2033 ,  G09G3/288 ,  G09G2320/0261 ,  G09G2320/0266 ,  G09G2320/106

摘要： With the new plasma display panel technology new kinds of artefacts can occur in video pictures. These artefacts are commonly described as "dynamic false contour effect", since they correspond to disturbances of gray levels and colors in the form of an apparition of colored edges in the picture when the observation point on the PDP screen moves. Often, such an artefact is compensated by analyzing the motion in the pictures, assigning to a pixel a corresponding motion vector (MV) and performing a re-coding step in which the different sub-fields code word entries of a pixel are shifted to distribute the sub-fields of a pixel more closely on the eye trajectory. It is disclosed a procedure for transforming the motion vectors into a more symmetrical form before applying the compensation in order to better respect the symmetry of the human visual system. It has prooved to be advantageous to better make an under-compensation by rounding down the motion vector components irrespective of their rational component value before symmetrization. A further aspect of the invention is a specific rounding process used for calculating the correction pixel locations when making a correction on signal amplitude level instead of sub-field level.

公开(公告)号：EP1224657A1

公开(公告)日：2002-07-24

申请号：EP00967807.9

申请日：2000-09-27

申请人： Thomson Licensing S.A.

发明人： WEITBRUCH, Sébastien ,  CORREA, Carlos ,  ZWING, Rainer

IPC分类号： G09G3/28

CPC分类号： G09G3/2033 ,  G09G3/2003 ,  G09G3/2029 ,  G09G3/294 ,  G09G2320/0261 ,  G09G2320/0266 ,  G09G2320/106

摘要： With the new plasma display panel technology new kinds of artefacts can occur in video pictures due to the principle that brightness control is done with a modulation of small lighting pulses in a number of periods called sub-fields. These artefacts are commonly described as 'dynamic false contour effect'. To compensate for this effect motion estimators are used and with the resulting motion vectors corrected sub-field code words are calculated for the critical pixels. Today's motion estimators work with the luminance signal component of the pixels. This is not sufficient for plasma displays. It is therefore proposed to make the motion vector calculation separately for the color components and with either the sub-field code words as data input or with single bit data input for performing motion estimation separately for single sub-fields or for a sub-group of bits from the sub-field code words. The proposal also concerns apparatuses for performing the inventive method.

公开(公告)号：EP1224655A1

公开(公告)日：2002-07-24

申请号：EP00953126.0

申请日：2000-07-31

申请人： Thomson Licensing S.A.

发明人： CORREA, Carlos ,  WEITBRUCH, Sébastien ,  ZWING, Rainer

IPC分类号： G09G3/28

CPC分类号： G09G3/2033 ,  G09G3/2029 ,  G09G3/288 ,  G09G2320/0266 ,  G09G2330/045 ,  G09G2360/16

摘要： Plasma Display Panels are becoming more and more interesting for TV technology. One important criterion for picture quality is the Peak White Enhancement Factor PWEF. In a previous patent application a method for power level control in a display with which the PWEF can be increased has been proposed. With an increased PWEF the problem of local overheating of plasma cells may occur. This invention proposes a protection circuit, which deals with this problem. For protecting the plasma display against local overheating, there is provided a method, which performs the steps of local power value determination, local temperature estimation, maximum local temperature determination and maximum power level limit determination. The power level limit influences the power level control process in the display device so that local overheating is avoided and the highest possible PWEF can be used. The invention also concerns a corresponding apparatus for carrying out the proposed method.