Quantization method and system for video MPEG applications and computer program product therefor

The method of claim further comprising:

• subjecting each said coefficient to a first quantization step in the absence of any said dither signal being added to generate an undithered quantized coefficient;
• and
• checking if said undithered quantized coefficient is equal to zero, such that
• when said undithered quantized coefficient is equal to zero, taking said undithered quantization coefficient as said quantized signal, and
• when said undithered quantized coefficient is different from zero, adding said dither signal to said coefficient and subjecting said dithered coefficient to a quantization step to generate said quantized signal.

A system for converting digital signals between a first and second format, the system being configured for generating coefficients representative of said digital signals comprising:

• at least one quantizer for subjecting said coefficients to quantization;
• a source of a dither signal;
• and
• an adder for adding said dither signal to said coefficients before said quantization to generate a quantized signal.

A computer program product directly loadable in the internal memory of a digital computer and including software code portions for performing, when the product is run on a computer, a method of converting digital signals between a first and a second format, the method comprising:

• generating coefficients representative of said digital signals;
• subjecting said coefficients to quantization;
• generating a dither signal;
• and
• adding said dither signal to said coefficients before said quantization to generate a quantized signal.