1. An electronic device comprising: an image sensor that captures an image that includes n image areas, wherein n is at least one; storage and processing circuitry that manipulates depth of field in the image by processing the image, wherein the storage and processing circuitry is configured to manipulate the depth of field of the image by: calculating an inferred defocus metric for each of the n image areas; for x of the n image areas, sharpening each of the x image areas by an amount the depends on the calculated inferred defocus metric for that image area, wherein the storage and processing circuitry is configured to determine how much sharpening to apply to each of the x image areas using a stored sharpness strength characteristic that relates sharpening strength to image area signal-to-noise ratio values and that has both positive and negative slopes; and for y of the n image areas, smoothing each of the y image areas by an amount the depends on the calculated inferred defocus metric for that image area, wherein the storage and processing circuitry is configured to determine how much smoothing to apply to each of the y image areas using the stored sharpness strength characteristic, wherein the sum of x and y is n, wherein x is no less than zero and no greater than n, and wherein y is no less than zero and no greater than n.