Hi-speed deterministic approach in detecting defective pixels within an image sensor

DETAILED DESCRIPTION OF THE INVENTION Referring to the figures, exemplary embodiments of the invention will now be described.
The exemplary embodiments are provided to illustrate aspects of the invention and should not be construed as limiting the scope of the invention.
The exemplary embodiments are primarily described with reference to block diagrams or flowcharts.
As to the flowcharts, each block within the flowcharts represents both a method step and an apparatus element for performing the method step.
Depending upon the implementation, the corresponding apparatus element may be configured in hardware, software, firmware or combinations thereof.
FIG.
1 is a flow diagram of an embodiment of the invention.
In the various embodiments of the invention, a deterministic software approach to defective pixel detection is disclosed.
When an image capture device such as a digital camera is connected to host machine such as a PC (Personal Computer), this approach may be executed so that a hardware on-device map of defective pixel locations need not be maintained.
A pre-defined number of input images are first scanned by the imaging device.
For each pixel, a "Defective Vote" score is tallied by checking a condition which considers a neighborhood of the pixel under consideration.
For each scanned image in which the condition is satisfied, the score is increased.
When the score is tallied for all the scanned images, the defective decision is reached.
If the pixel is found to be defective, it is written to a map stored on the host.
The process is repeated until all pixel locations in the imaging device have been classified.
The map of defective pixel locations is stored on the host and can be accessed when an image captured by the imaging device needs to be enhanced, filtered or otherwise processed.
With this framework in mind, FIG.
1 illustrates a logic flow that can achieve defective pixel detection in a deterministic manner.
First, the camera or imaging device containing the sensor under examination is connected to a host such as a PC