Signal-correlated noise estimating method for image sensor

An image sensor and signal-related technology, applied in image communication, image enhancement, image data processing, etc., can solve the problems of estimation, poor effect and high computational complexity

Active Publication Date: 2012-07-25
TIANJIN UNIV
View PDF1 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This type of method can better realize the estimation of the CCD noise curve, but also has a high computational complexity
At the same time, since this method is based on i...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Signal-correlated noise estimating method for image sensor
  • Signal-correlated noise estimating method for image sensor
  • Signal-correlated noise estimating method for image sensor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0092] The technical problem to be solved by the present invention is to propose a method of estimating noise samples through smooth image blocks, and then using these noise sample values ​​and the credibility of the sample values ​​to reconstruct the noise level function (NLF) curve using sparse representation technology Methods. This method should not only be able to accurately estimate the noise function of different CCD images, but also not increase the computational complexity.

[0093] Technical scheme of the present invention is:

[0094]A method based on the image structure rather than the traditional method of calculating the variance of image blocks is used to find the smooth blocks of the image. Then these blocks are sampled according to the arrangement of the color filter matrix CFA to obtain a set corresponding to each gray value, and the mean and variance of this set are calculated to obtain a set of noise estimation sample points. At the same time, the reliabi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a computer image processing and visual detecting genecology. In order to provide a method which can exactly estimate the noise function of different CCD (charge coupled device) images and further can not increase the computing complexity, the technical scheme adopted by the invention is as follows: a signal-correlated noise estimating method for an image sensor comprises the following steps of: searching smooth blocks of an image by adopting a high pass operator-based image structure analyzer; sampling the blocks according to the arrangement mode of CFA (colorful filter array), to obtain a set which corresponds to each gray value, and computing the mean value and variance of the set, to obtain a set of noise estimating sample points; according the smoothness degree of the set of the image block of each sample point, computing the reliability of the sample point; and finally in combination with the sample points, the reliability of the sample points and the base obtained by using PCA (principal component analysis) in advance, rebuilding a noise horizontal curve by a sparse representation technology. The method is mainly used for processing the image.

Description

technical field [0001] The invention relates to computer image processing and visual detection technology, in particular to a method for estimating signal-dependent noise of an image sensor. Background technique [0002] In recent years, with the popularity of digital cameras and mobile phones with cameras, human beings have entered the digital age for all, and image sensors, which are the core components of digital cameras, have naturally become more and more important. There are currently two types of image sensors commonly used: CCD (Charge-Coupled Device) sensors and CMOS sensors. Among them, electronically coupled devices (CCDs) have been widely used due to their advantages such as self-scanning, high resolution, low output noise, large dynamic range, high quantum efficiency, high charge transfer efficiency, wide spectral response range, and good geometric stability. It is used in fields such as camera, image acquisition, scanner and industrial measurement. [0003] H...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G06T5/00H04N5/357
Inventor 杨敬钰吴兆阳侯春萍
Owner TIANJIN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products