Wide dynamic range digital image composition
AssigneeFUJIFILM Corporation
InventorNobuo Suzuki
Life of this patent
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Abstract
An image composition method comprises: composing a high-sensitivity image signal H and a low-sensitivity image signal L, so as to generate a composite image signal Gc according to a composing expression: Gc=k·H+(1−k)·L where k is a composite parameter satisfying 0≦k≦1, wherein the high-sensitivity image signal H is generated based on high-sensitivity image outputs from corresponding ones of a plurality of pixel positions in a solid-state imaging element that has imaged a subject; the low-sensitivity image signal L is generated based on low-sensitivity image outputs from corresponding ones of the plurality of pixel positions in the solid-state imaging element; and the composing is performed at every common pixel position by determining k at every common pixel position.
Claims17
An image composition method comprising:
- composing a high-sensitivity image signal H and a low-sensitivity image signal L, so as to generate a composite image signal Gc according to a composing expression:
- Gc=k·H+(1−k)·L
- where k is a composite parameter satisfying 0≦k≦1,
- wherein the high-sensitivity image signal H is generated based on high-sensitivity image outputs from corresponding ones of a plurality of pixel positions in a solid-state imaging element that has imaged a subject;
- the low-sensitivity image signal L is generated based on low-sensitivity image outputs from corresponding ones of the plurality of pixel positions in the solid-state imaging element;
- the composing is performed at every common pixel position by determining k at every common pixel position;
- wherein the high-sensitivity image signal H is a signal GH(DH) obtained by converting a high-sensitivity image signal DH with a nonlinear characteristic GH for a high-sensitivity image signal, the high-sensitivity image signal DH being generated based on the high-sensitivity image outputs;
- and
- the low-sensitivity image signal L is a signal GL(DL) obtained by converting a low-sensitivity image signal DL with a nonlinear characteristic GL for a low-sensitivity image signal, the low-sensitivity image signal DL being generated based on the low-sensitivity image outputs;
- and
- wherein the nonlinear characteristic GH for the high-sensitivity signal and the nonlinear characteristic GL for the low-sensitivity signal have a characteristic of realizing a monotonously-increasing function, whose change in a secondary differential value is positive or zero at all times.
A solid-state imaging device comprising:
- a solid-state imaging element comprising a plurality of pixel positions, the solid-state imaging element imaging a subject;
- and
- an image processing portion that composes a high-sensitivity image signal H and a low-sensitivity image signal L, so as to generate a composite image signal Gc according to a composing expression:
- Gc=k·H+(1−k)·L
- where k is a composite parameter satisfying 0≦k≦1,
- wherein the high-sensitivity image signal H is generated based on high-sensitivity image outputs from corresponding ones of the plurality of pixel positions;
- the low-sensitivity image signal L is generated based on high-sensitivity image outputs from corresponding ones of the plurality of pixel positions;
- the composing is performed at every common pixel position by determining k at every common pixel position;
- wherein the high-sensitivity image signal H is a signal GH(DH) obtained by converting a high-sensitivity image signal DH with a nonlinear characteristic GH for a high-sensitivity image signal, the high-sensitivity image signal DH being generated based on the high-sensitivity image outputs;
- and
- the low-sensitivity image signal L is a signal GL(DL) obtained by converting a low-sensitivity image signal DL with a nonlinear characteristic GL for a low-sensitivity image signal, the low-sensitivity image signal DL being generated based on the low-sensitivity image outputs;
- and
- wherein the nonlinear characteristic GH for the high-sensitivity signal and the nonlinear characteristic GL for the low-sensitivity signal have a characteristic of realizing a monotonously-increasing function, whose change in a secondary differential value is positive or zero at all times.
Dependencies are inferred from the claim text.