Imaging apparatus, imaging method, integrated circuit, and storage medium
First Claim
Patent Images
1. An imaging apparatus comprising:
- an optical system operable to adjust an exposure light amount;
an A/D converter operable to convert an analogue signal that is obtained by the optical system to a first digital signal;
a dynamic-range increasing unit operable to magnify the first digital signal with a dynamic range magnification ratio to generate a second digital signal;
a control unit operable to generate control signals, one for decreasing the exposure light amount and the other for increasing the dynamic range magnification ratio; and
a dynamic-range compression unit including;
a vicinity luminance detection unit operable to extract a vicinity luminance value of the second digital signal corresponding to a predetermined position; and
a dynamic tone correction unit operable to convert an input value of the second digital signal for the predetermined position to an output value of the second digital signal for the predetermined position by using a conversion characteristic,wherein the conversion characteristic changes the output value according to the vicinity luminance value, andwherein a gradient of the conversion characteristic at a point corresponding to the vicinity luminance value is the same as or greater than a gradient of a straight line from a coordinate origin passing through the point on the conversion characteristic corresponding to the vicinity luminance value.
1 Assignment
0 Petitions
Accused Products
Abstract
An imaging apparatus captures a large dynamic range image of a scene including a backlit person with a blue sky background in a manner that the person'"'"'s face has an appropriate luminance level without saturating the background sky. An imaging unit obtains analogue image signals through exposure control that prevents a highlight from being saturated, an A/D converter converts the analogue image signals to digital image signals, and a signal processing unit linearly increases the dynamic range of the digital image signals. The image signals with the increased dynamic range are nonlinearly compressed to have a dynamic range of 100% or less through nonlinear dynamic range compression that intensively compresses a highlight portion. The imaging apparatus with this structure first increases the dynamic range of an image and efficiently compresses the increased large dynamic range of the image.
22 Citations
11 Claims
-
1. An imaging apparatus comprising:
-
an optical system operable to adjust an exposure light amount; an A/D converter operable to convert an analogue signal that is obtained by the optical system to a first digital signal; a dynamic-range increasing unit operable to magnify the first digital signal with a dynamic range magnification ratio to generate a second digital signal; a control unit operable to generate control signals, one for decreasing the exposure light amount and the other for increasing the dynamic range magnification ratio; and a dynamic-range compression unit including; a vicinity luminance detection unit operable to extract a vicinity luminance value of the second digital signal corresponding to a predetermined position; and a dynamic tone correction unit operable to convert an input value of the second digital signal for the predetermined position to an output value of the second digital signal for the predetermined position by using a conversion characteristic, wherein the conversion characteristic changes the output value according to the vicinity luminance value, and wherein a gradient of the conversion characteristic at a point corresponding to the vicinity luminance value is the same as or greater than a gradient of a straight line from a coordinate origin passing through the point on the conversion characteristic corresponding to the vicinity luminance value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An imaging method, comprising:
-
adjusting an exposure light amount; converting an analogue signal that is obtained by the optical system to a first digital signal; magnifying the first digital signal with a dynamic range magnification ratio to generate a second digital signal; and generating control signals, one for decreasing the exposure light amount and the other for increasing the dynamic range magnification ratio, the step of generating the control signals including; extracting a vicinity luminance value of flail the second digital signal corresponding to a predetermined position; and converting an input value of flail the second digital signal for flail the predetermined position to an output value of the second digital signal for the predetermined position by using a conversion characteristic, wherein the conversion characteristic changes the output value according to the vicinity luminance value, and wherein a gradient of the conversion characteristic at a point corresponding to the vicinity luminance value is the same as or greater than a gradient of a straight line from a coordinate origin passing through the point on the conversion characteristic corresponding to the vicinity luminance value. - View Dependent Claims (10, 11)
-
Specification
-
- Resources
Litigation Campaign Assessment
Thank you for your request. You will receive a custom alert email when the Litigation Campaign Assessment is available.
×
-
Current AssigneePanasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
-
Original AssigneePanasonic Corporation (Panasonic Holdings Corporation)
-
InventorsYamashita, Haruo, Ito, Takeshi, Sato, Daisuke
-
Primary Examiner(s)Hernndez Hernndez, Nelson D.
-
Assistant Examiner(s)HOGUE, DENNIS A
-
Application NumberUS13/222,313Publication NumberTime in Patent Office685 DaysField of SearchNoneUS Class Current348/254CPC Class CodesH04N 23/71 Circuitry for evaluating th...H04N 23/72 Combination of two or more ...H04N 23/741 by increasing the dynamic r...
