Device for indicating the position of a window in a display and for enhancing an image in the window

A display apparatus comprising:

• a display device;
• a picture enhancement circuit for receiving display data and a control signal and for supplying enhanced display signals to the display device during a period of time indicated by the control signal;
• and
• a control circuit for receiving:
• reference information indicating a first time of occurrence and a corresponding first running number of a first predetermined pixel, and a second time of occurrence and a corresponding second running number of a second predetermined pixel of the display data, and
• coordinates determining a window of the display data, said control circuit supplying the control signal indicating a start instant of the window, the start instant being calculated from the coordinates and the reference information, characterized in that the control circuit determines the start instant (tc1) as
• tc1=((Nm2−Nc1)*tm1+(Nc1−Nm1)*tm2)/(Nm2−Nm1),
• where Nm1 is the first running number, Nm2 is the second running number, Nc1 is a first of said coordinates, tm1 is the first time of occurrence, and tm2 is the second time of occurrence.

A display apparatus comprising:

• a display device;
• a picture enhancement circuit for receiving display data and a control signal and for supplying enhanced display signals to the display device during a period of time indicated by the control signal;
• and
• a control circuit for receiving:
• reference information indicating a first time of occurrence and a corresponding first running number of a first predetermined pixel, and a second time of occurrence and a corresponding second running number of a second predetermined pixel of the display data, and
• coordinates determining a window of the display data, said control circuit supplying the control signal indicating a start instant of the window, the start instant being calculated from the coordinates and the reference information,
• characterized in that the first predetermined pixel is the first pixel in a line, and that the second predetermined pixel is the last pixel in said line, the first time of occurrence being the time of occurrence of the first pixel, the second time of occurrence being the time of occurrence of the last pixel, and the reference information indicating a total number of pixels occurring in said line, and the control circuit determines the start instant (tc1) as
• tc1=Nc1*T/N
• wherein Nc1 is the first running number, the line period T is the duration of a video line from the first video pixel to the last video pixel, and N is the number of video pixels occurring during the line period T.