Image stabilization device and method
View Patent ↗An imaging device and processes to provide image stabilization by controlling analog gain and integration time. Analog gain and integration time for images are determined by comparing an image in various frames, whether full frames or hidden frames, where the image is provided with differently set analog gain and integration time settings to determine settings for stabilized image capture.
1. A method of image stabilization, comprising:
capturing a first image frame using a first set of gain and integration parameters, comprising analog gain and integration time based on image brightness;
defining a first sub-part of the first image frame;
determining a first sharpness score for the first sub-part;
capturing a second image frame using a second set of gain and integration parameters, comprising a maximum analog gain setting;
determining a second sharpness score for the second image frame based on at least a second sub-part of the second image frame;
comparing the second sharpness score to the first sharpness score;
adjusting analog gain and integration time for a next captured image based on the comparison of the second sharpness score to the first sharpness score; and
capturing a third image frame using an analog gain setting between the setting for the first image frame and the maximum analog gain.
2. The method of claim 1 , further comprising determining a third sharpness score for a third sub-part of the third image frame.
3. The method of claim 2 , further comprising comparing the first, second, and third sharpness scores and determining analog gain and integration time settings based upon this comparison.
4. A method of image stabilization, comprising:
receiving an image at a first frame using a first analog gain based on image brightness;
defining a sub-frame of the first frame;
determining a first sharpness score for the sub-frame;
receiving a second frame of the image using maximum analog gain;
determining a second sharpness score for a second sub-frame of the second frame;
receiving a third frame of the image using an intermediate analog gain relative to that used for the first and second frames;
determining a third sharpness score for a third sub-frame of the third frame;
comparing the first, second, and third sharpness scores; and
setting a final analog gain and an integration time based on the comparison of the first, second, and third sharpness scores.
5. The method of claim 4 , wherein if the difference between a highest and lowest of the first, second, and third sharpness scores is within a predetermined range, the analog gain used for the first frame is used to save the image.
6. The method of claim 4 , wherein if the third sharpness score is closer to the second sharpness score than to the first sharpness score, the analog gain setting used for the third frame is used for a saved image.
7. The method of claim 4 , wherein if the third sharpness score is closer to the first sharpness score than to the second sharpness score, the analog gain setting used for the second frame is used for a saved image.