US 6,642,961 B1Granted

Method of defective pixel address detection for image sensors having windowing function

AssigneeVanguard International Semiconductor Corporation

InventorMing-Tsun Hsieh

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method of defective pixel address detection for an image sensor. The method comprises comparing a defective pixel address with a sensor address; outputting a defective pixel flag if the sensor address is equal to the defective pixel address; increasing an index by one; increasing the index by one if the sensor address is larger than the defective pixel address and the index value is not equal to zero, otherwise performing a following step; increasing the index by one if the sensor address is larger than the defective pixel address and the index value is equal to zero and a frame begins, otherwise performing a following step; comparing the defective pixel address with an empty signature; increasing the index by one if the defective pixel address is equal to the empty signature; and returning to the beginning step if the defective pixel address is not equal to the empty signature.

Claims9

Dependent claims

A method of defective pixel address detection for an image sensor, comprising:

(a) comparing a defective pixel address with a sensor address of the image sensor, wherein the defective pixel address is stored in a memory element in advance when the image sensor is tested;
(b) outputting a defective pixel flag if the sensor address is equal to the defective pixel address;
(c) increasing an index value by one unit and returning to the step (a);
(d) increasing the index value by one unit and returning to the step (a) if the sensor address is larger than the defective pixel address and the index value is not equal to zero, otherwise performing a following step (e);
(e) increasing the index value by one unit and returning to the step (a) if the sensor address is larger than the defective pixel address and the index value is equal to zero and a frame begins, otherwise performing a following step (f);
(f) comparing the defective pixel address with an empty signature;
(g) increasing the index value by one unit if the defective pixel address is equal to the empty signature, and returning to the step (a);
and
(h) returning to the step (a) if the defective pixel address is not equal to the empty signature.

6 more elements

A method of defective pixel address detection for an image sensor, comprising the steps of:

storing a plurality of defective pixel addresses during the image sensor is tested;
reading a pixel address of the image sensor;
fetching one of the defective pixel addresses;
comparing the first fetched defective pixel address with the pixel address of the sensor address;
outputting a defective pixel flag if the pixel address is equal to the defective pixel address;
increasing an index value by one unit and fetching another defective pixel address which is indexed next to the first fetched defective pixel address;
comparing the first fetched defective pixel address with the pixel address of the sensor address and further determining the index value if the pixel address is not equal to the defective pixel address;
increasing an index value by one unit and fetching another defective pixel address which is indexed next to the first fetched defective pixel address if the pixel address of the sensor address is larger than the first fetched defective pixel address and the index is not equal to zero;
further determining whether a frame begins if the pixel address of the sensor address is not larger than the first fetched defective pixel address or the index is equal to zero;
increasing an index value by one unit and fetching another defective pixel address which is indexed next to the first fetched defective pixel address if the pixel address of the sensor address is larger than the first fetched defective pixel address and the index is equal to zero and the frame begins;
comparing the defective pixel address with an empty signature if the pixel address of the sensor address is not larger than the first fetched defective pixel address and the index is not equal to zero and no frame begins;
increasing the index value by one unit if the defective pixel address is the empty signature, and then fetching another defective pixel address which is indexed next to the first fetched defective pixel address;
and
fetching another defective pixel address which is indexed next to the first fetched defective pixel address if the defective pixel address is not the empty signature.

11 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/671,566Filed 27 Sep 2000 · us provisional application
Priority: 12 Jul 2000
Granted: 4 Nov 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

H04N 23/667
Control of cameras or camera modules: camera operation mode switching, e.g. between still and video, sport and normal or high- and low-resolution…
H04N 25/44
Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled: by…
H04N 25/68
Noise processing, e.g. detecting, correcting, reducing or removing noise: applied to defects
H04N
Pictorial communication