On screen display arrangement for a digital video signal processing system

Apparatus comprising:

• a source of a sequence of digital words representing respective components of a video image and organized in repetitive video image groups;
• each of said video image groups corresponding to two picture elements and including a first luminance component corresponding to a first picture element of said two picture elements, a second luminance component corresponding to a second picture element of said two picture elements, and two color difference components corresponding to each of said two picture elements;
• a memory for storing a sequence of digital words representing respective components of a graphics image and organized in repetitive graphics image groups;
• each of said graphics image groups corresponding to one picture element and including a luminance component and two color difference components corresponding to said picture element;
• a converter coupled to said memory for converting respective pairs of sequential graphics image groups stored in said memory to new graphic image groups;
• each of said new graphics image groups corresponding to two picture elements and including a first luminance component corresponding to a first picture element of said two picture elements, a second luminance component corresponding to a second picture element of said two picture elements, and two color difference components corresponding to each of said two picture elements;
• and
• a multiplexer responsive to said video image groups and to said new graphics image groups for selecting either said video image groups or said graphics image groups to produce a sequence of resultant image groups;
• each of said resultant image groups corresponding to two picture elements and including a first luminance component corresponding to a first picture element of said two picture elements, a second luminance component corresponding to a second picture element of said two picture elements, and two color difference components corresponding to each of said two picture elements.

Apparatus comprising:

• a source of a sequence of digital words representing respective components of a video image and organized in repetitive video image groups;
• each of said video image groups corresponding to a number N, more than one, of picture elements and including a number N of luminance components corresponding to respective ones of said N picture elements and two color difference components corresponding to each of said N picture elements;
• a memory for storing a sequence of digital words representing respective components of a graphics image and organized in repetitive graphics image groups;
• each of said graphics image groups corresponding to one picture element and including a luminance component and two color difference components corresponding to said picture element;
• a converter coupled to said memory for converting respective ones of said graphics image groups stored in said memory to new graphic image groups;
• each of said new graphics image groups corresponding to N picture elements and including N luminance components corresponding to respective ones of said N picture elements and two color difference components corresponding to each of said N picture elements;
• and
• a multiplexer responsive to said video image groups and to said new graphics image groups for selecting either said video image groups or said graphics image groups to produce a sequence of resultant image groups;
• each of said resultant image groups corresponding to N picture elements and including N luminance components corresponding to respective ones of said N picture elements and two color difference components corresponding to each of said N picture elements.