Patent · US Expired

Image processing apparatus with improved data conversion testing

US5544240A · kind A · utility

6Cited by
6References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 31, 1995
Grant dateAug 6, 1996
Priority date
Expiry dateJan 31, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/66
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image processing apparatus comprises a first memory for storing a plurality of data words corresponding to different pixels of a test image, each data word being set to a common test data value. The data words are converted into one or more analog video signals using an digital to analog convertor. The one or more video signals are converted, using an analog to digital convertor, into captured data values with each captured data value corresponding to a different one of the data words stored in the first memory. The captured data values are stored in a second memory and averaged to generate a mean captured value. Any difference between the mean captured value and the test data value is determined to identify any amplification error in the captured data values. First and second tolerance values are set to be respectively greater than and less than the mean captured value. The captured data values between the first and second tolerance limits are then counted to identify any quantization errors in the captured data values.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.