Method and circuit for forming on-screen displays for overlay on a video image

A machine-readable medium encoded with a program for displaying an OSD on a video image, said program containing instructions for performing the steps of:

• storing values of pixels of the OSD;
• displaying pixels of lines of the OSD that are to be displayed without processing by making direct use of a color look-up table;
• and
• processing pixels of lines of the OSD that are to be displayed after processing with a mathematical filter and/or that are required for computations associated with the mathematical filter,
• wherein the processing step includes the sub-steps of:
• storing the pixels of the lines to be processed in the form of addresses that designate the memory lines of the color look-up table;
• obtaining the values of the pixels of the lines to be processed by an addressing of the color look-up table;
• and
• applying a mathematical filter to the obtained values of the pixels to be processed.

A device for displaying an OSD on a video image, said device comprising:

• a processing interface;
• a first memory module;
• a color look-up table capable of being addressed by both the processing interface and the first memory module;
• an OSD insertion module;
• and
• a control unit that, for each pixel, selectively sends data elements from the color look-up table to either the processing interface or the OSD insertion module.

A device for displaying an OSD on a video image, said device comprising:

• storage for storing values of pixels of the OSD;
• means for displaying pixels of lines of the OSD that are to be displayed without processing by making direct use of a color look-up table;
• and
• means for processing pixels of lines of the OSD that are to be displayed after processing with a mathematical filter and/or that are required for computations associated with the mathematical filter,
• wherein the means for processing includes:
• means for storing the pixels of the lines to be processed in the form of addresses that designate the memory lines of the color look-up table;
• means for obtaining the values of the pixels of the lines to be processed by an addressing of the color look-up table;
• and
• means for applying a mathematical filter to the obtained values of the pixels to be processed.