·         Uniform

·         Non uniform quantization

Uniform Quantizer: In Uniform type, the quantization levels are uniformly spaced, whereasin non-uniform type the spacing between the levels will be unequal and mostly the relation is logarithmic. 

Types of Uniform Quantizers: ( based on I/P – O/P Characteristics)

 1. Mid-Rise type Quantizer

 2. Mid-Tread type Quantizer

 In the stair case like graph, the origin lies the middle of the tread portion in Mid –Tread type where as the origin lies in the middle of the rise portion in the Mid-Rise type.

 Mid – tread type:Quantization levels – odd number.

 Mid – Rise type: Quantization levels – even number.