Image processing noise reduction
AssigneeContrast, Inc.
InventorsWillie C. Kiser, Michael D. Tocci, Nora Tocci
Life of this patent
Estimating the term…
Abstract
Noise reduction in images is provided by performing a noise reduction step on blocks of pixels within a video-processing pipeline. The noise reduction step consists of applying a discrete cosine transform (DCT) to the block of pixels, quantizing the resulting DCT coefficients, and performing an inverse of the DCT to the quantized coefficients. The output of that noise reduction step is a block of image pixels similar to the input pixels, but with significantly less image noise. Because the noise reduction step can be performed quickly on small blocks of pixels, the noise reduction can be performed in real-time in a video processing pipeline.
Claims15
A method of image noise reduction, the method comprising:
- obtaining image data from at least one image sensor;
- performing a discrete cosine transform (DCT) on the image data to obtain DCT values,
- quantizing the DCT values, and
- conducting an inverse DCT and inverse quantization, thereby to produce noise-reduced image data.
A method for removing noise from a real-time stream of digital image data, the method comprising:
- receiving data from at least one image sensor;
- applying a noise reduction pipeline to remove noise from the data, wherein the pipeline includes:
- downsampling at least a portion of the data in order to remove a first portion of the noise,
- frequency domain processing the data to remove a second portion of the noise, the processing including:
- converting the data into the frequency domain, wherein the data are expressed as a combination of distinct frequencies,
- identifying a portion of said distinct frequencies as being associated with a second portion of the noise,
- removing the identified portion of said distinct frequencies,
- converting remaining image data to yield noise-reduced image data;
- and
- providing the data for displaying, broadcasting, or storing as a digital image.
Dependencies are inferred from the claim text.