Module symphonia_core::conv::dither

The dither module provides methods to apply a dither to a sample.

Dithering is the process of adding noise to the least significant digits of a sample before down-converting (quantizing) it to a smaller sample type. The purpose of dithering is to decorrelate the quantization error of the down-conversion from the source signal.

Dithering is only applied on lossy conversions. Therefore the dither module will only apply a dither to the following down-conversions:

• { i32, u32 } to { i24, u24, i16, u16, i8, u8 }
• { i24, u24 } to { i16, u16, i8, u8 }
• { i16, u16 } to { i8, u8 }

Multiple dithering algorithms are provided, each drawing noise from a different probability distribution. In addition to different distributions, a dithering algorithm may also shape the noise such that the bulk of the noise is placed in an inaudible frequency range.

Structs

• Identity
  The Identity dithering algorithm performs no dithering and returns the original sample.
• RandomNoise
  RandomNoise represents a sample of noise of a specified length in bits.
• Rectangular
  Rectangular implements a dither using uniformly distributed (white) noise without shaping.
• Triangular
  Triangular implements a dither using a triangular distribution of noise without shaping.

Enums

• DitherType
  Enumeration of dither algorithms.

Traits

• AddNoise
  AddNoise is a trait for converting random noise into a Sample.
• Dither
  Dither is a trait for implementing dithering algorithms.
• MaybeDither
  MaybeDither conditionally applies a dither to a sample depending on the source and destination sample types.