High dynamic range image sensor

摘要

This disclosure describes techniques for producing high dynamic range images by applying a variable weighting factor to a sample prior to combining the sample with another sample. In one example, a method includes sampling a first pixel cell signal at a first time to produce a first sample, sampling a second pixel cell signal at a second time to produce a second sample, applying a variable weighting factor to the second sample, wherein the variable weighting factor is defined based on a function, and combining the first sample and the weighted second sample.

主权项

1. A method comprising:
sampling a first pixel cell signal at a first time to produce a first sample; sampling a second pixel cell signal at a second time to produce a second sample; applying a first variable weighting factor to the first sample, wherein the first variable weighting factor is defined based on a first function; applying a second variable weighting factor to the second sample, wherein the second variable weighting factor is defined based on a second function; and combining the weighted first sample and the weighted second sample according to the equation:
SCOMBINED(i, j)=SLONG(i, j)*M(i, j)+n*SSHORT(i, j)*(1−M(i, j))where SCOMBINED denotes the combination of the first sample, denoted by SSHORT, and the second sample, denoted by SLONG, for the pixel cell located at (i, j), n denotes a scalar value that is dependent on the difference in the time of exposure between the first time and the second time, and M(i, j) denotes the variable weighting factor.