1. A method for analyzing a daytime image in a device, comprising: receiving an image that includes a plurality of pixels into the device; computing a histogram of the image; and, analyzing the histogram to determine an acceptable exposure of the image, wherein said analyzing the histogram includes: determining whether, in the histogram between a first summit and an adjacent second summit lower in intensity value than the first summit, there is a bin whose population is below a first threshold that is below the first summit, the first summit being highest in intensity value among all summits in the histogram and being associated with pixels with dominant brightness of a sky region in the image.