Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and digital video data, and is often one of the last stages of audio production to compact disc.
Hepatic porphyria. Hepatic porphyrias is a form of porphyria in which the enzyme deficiency occurs in the liver. Examples include (in order of synthesis pathway): Acute intermittent porphyria. Porphyria cutanea tarda and Hepatoerythropoietic porphyria.
The porphyrias are a group of uncommon diseases that cause either disease affecting the skin, disease affecting the nervous system, or both.cute intermittent porphyria. The next most common form of porphyria is acute intermittent porphyria or AIP. AIP causes only neurological symptoms and does not affect the skin. AIP is inherited but may appear to skip generations as many people who inherit the disease never get any symptoms.