Method and device for equalizing histogram based on sub-regional interpolation

Abstract

The invention relates to a method and a device for equalizing a histogram based on sub-regional interpolation. The method and the device are used for: acquiring and digitalizing an image; preprocessing the image; dividing data input by an image input module into a plurality of regions; performing histogram statistics on each region; performing contrast limited adjustment on histogram data and an input image; changing histogram distribution of the histogram data and the input image; redistributing overflow pixels to each histogram interval; performing histogram equalization on a result of the contrast limited histogram adjustment; dividing an image region into a plurality of sub-blocks; and performing interpolation processing on adjacent sub-blocks positioned in different regions. The idea of the invention is to analyze the histogram of an input source image on the basis of contrast limited histogram equalization technology, brighten the dark part in the source image through adaptive histogram specification technology and the processes of regional interpolation and the like, highlight more details, and prevent the brighter part from overexposure to lose an image detail at the same time.

Description

technical field [0001] The invention belongs to the field of computer video image processing, and relates to a histogram equalization method and device based on subregional interpolation. Background technique [0002] In scenes with large changes in light and shade, such as when reversing into or out of the garage, due to the normal sunlight outside the garage, the light inside the garage is obviously not as strong as outside due to the ceiling. For human eyes or cameras, Details outside the garage in full sunlight and details inside the garage in the shade become difficult to distinguish and make out, and for images captured by an on-board image acquisition device, the dynamic range of the image is too large to make some details difficult It is clearly presented, and these details are of important reference value for parking drivers, so I still hope to see the details of the bright parts outside and the details of the dark parts inside. Another example is that there is a l...

AI Technical Summary

Problems solved by technology

Another example is that there is a large difference between light and shade inside and outside the cave. The scene inside the cave is usually dark and the details are not obvious when shooting outside the cave.

When this kind of backlight occurs, the exposure time is usually adjusted to increase the average brightness of the entire frame image, but it is inevitable to overexpose other areas in the image when certain areas become visible. or details disappear

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