Image composition systems and methods
View Patent ↗An image composition system. The image composition system comprises an image detection unit and an image composition unit. The image detection unit detects marked parts in low dynamic range images. The low dynamic range images are images of the same scene taken at different exposure levels. The image composition unit sets exposure history data of the low dynamic range images according to the marked parts. The image composition unit then synthesizes the low dynamic range images into a high dynamic range image according to the exposure history data.
1. An image composition system, comprising:
an image detection unit, detecting at least one marked part in at least one low dynamic range image, wherein the low dynamic range images are images of the same scene taken in different exposure levels; and
an image composition unit, coupled to the image detection unit, setting exposure history data of the low dynamic range images according to the marked parts, and synthesizing the low dynamic range images into a high dynamic range image according to the exposure history data.
2. The image composition system as claimed in claim 1 , wherein the exposure history data is stored in a database.
3. The image composition system as claimed in claim 1 , wherein the marked parts comprise at least one deletion part and/or at least one reservation part.
4. The image composition system as claimed in claim 3 , wherein the deletion and the reservation parts are marked in the different low dynamic range images.
5. The image composition system as claimed in claim 3 , wherein the deletion and the reservation parts are marked in the same low dynamic range images.
6. The image composition system as claimed in claim 3 , wherein the low dynamic range images are divided into a marked image and at least one unmarked image according to each marked part, and the image composition unit further:
maps each reservation part to the corresponding areas of the unmarked images;
deletes the deletion parts from the marked images; and
synthesizes the marked images and unmarked images after deletion.
7. The image composition system as claimed in claim 1 , wherein the image composition unit further comprises:
a partial composition unit, coupled to the image detection unit, synthesizing the marked parts, setting the exposure history data of the low dynamic range images according to the marked parts, and obtaining at least one partial synthesized image according to the exposure history data;
a standard composition unit, coupled to the image detection unit, synthesizing unmarked parts of the low dynamic range images to obtain at least one standard synthesized image; and
a digital blending unit, coupled to the partial composition unit and the standard composition unit, digitally blending the partial synthesized images and the standard synthesized images into the high dynamic range image.
8. The image composition system as claimed in claim 7 , wherein if the partial composition unit or the standard composition unit cannot synthesize images according to the exposure history data, a response function is referred for image composition, wherein the response function is calculated by:
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wherein E is a theoretical brightness value, g is the response function, L is a pixel value, Δt is exposure time, i is pixel number, j and k are exposure times, and M and X are the numbers of the low dynamic range images.
9. An image composition method, comprising:
providing at least one low dynamic range image, wherein the low dynamic range images are images of the same scene taken in different exposure levels;
detecting at least one marked part in the low dynamic range images;
setting exposure history data of the low dynamic range images according to the marked parts; and
synthesizing the low dynamic range images into a high dynamic range image according to the exposure history data.
10. The image composition method as claimed in claim 9 , wherein the exposure history data is stored in a database.
11. The image composition method as claimed in claim 9 , wherein the marked parts comprise at least one deletion part and/or at least one reservation part.
12. The image composition method as claimed in claim 11 , wherein the deletion part and the reservation part are marked in the different low dynamic range images.
13. The image composition method as claimed in claim 11 , wherein the deletion part and the reservation part are marked in the same low dynamic range images.
14. The image composition method as claimed in claim 11 , wherein the low dynamic range images are divided into a marked image and at least one unmarked image according to each marked part, the composition further comprising:
mapping each reservation part to the corresponding areas of the unmarked images;
deleting the deletion parts from the marked images; and
synthesizing the marked images and unmarked images after deletion.
15. The image composition method as claimed in claim 9 , wherein the composition further comprises:
synthesizing the marked parts of the low dynamic range images and setting the exposure history data of the low dynamic range images;
obtaining at least one partial synthesized image according to the exposure history data;
synthesizing unmarked parts of the low dynamic range images to obtain at least one standard synthesized image; and
blending digitally the partial synthesized images and the standard synthesized images into the high dynamic range image.
16. The image composition method as claimed in claim 15 , wherein if the images cannot be synthesized according to the exposure history data, a response function is referred for image composition, wherein the response function is calculated by:
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wherein E is a theoretical brightness value, g is the response function, L is a pixel value, Δt is exposure time, i is pixel number, j and k are exposure times, and M and X are the numbers of the low dynamic range images.