Method and system for generating a foreground mask for a composite image

A method for producing a subject mask from a digital image for use in a compositing process, said method comprising the steps of:

• a) receiving two digital images, each having a plurality of pixels, wherein a first digital image is derived from a first original scene image including a subject photographed against a background having arbitrary and unknown content matter, and a second digital image is derived from a second original scene image including substantially the same background matter without the subject;
• and,
• b) automatically processing the second digital image in relation to the first digital image to generate an aligned digital image including the background matter without the subject, wherein the automatic processing is achieved through a homographic transformation without user intervention;
• and,
• c) using the first digital image and the aligned digital image to produce a subject mask relating to an area in the first digital image pertaining to the subject, whereby the subject mask is used to generate a composite digital image.

A system for producing a foreground mask from a digital image, said system comprising:

• a digital camera for capturing two digital images, each having a plurality of pixels, wherein a first digital image is obtained from a first original scene image including a foreground photographed against a background having arbitrary and unknown content matter, and a second digital image is obtained from a second original scene image including substantially the same background but without the foreground;
• and
• a processor for (a) automatically aligning the second digital image to the first digital image to generate an aligned digital image including the background without the foreground, wherein the automatic aligning is achieved without user intervention;
• and (b) using the first digital image and the aligned digital image to produce a foreground mask relating to an area in the first digital image pertaining to the foreground, whereby the foreground mask is subsequently used to generate a composite digital image.

A digital camera for capturing images that are subsequently useful in a compositing process, said camera comprising:

• an imaging device for capturing image data;
• a memory for storing the image data from the imaging device;
• a digital processing section coupled to the imaging device and the memory to enable the capture and storage of a first digital image including a subject photographed against a background;
• an electronic view finder coupled to the digital processing section for displaying a portion of the first digital image in a first display zone on the view finder;
• and
• said digital processing section enabling the capture and display on the view finder of a second digital image including substantially the same background, but without the subject, in an overlapping relationship with the displayed portion of the first digital image, whereby the second digital image is displayed as a live image in a second display zone on the viewfinder to enable a user to coarsely align the live image with the first digital image before capturing the live image as the second digital image, thereby ensuring that the two images are captured from substantially the same viewpoint.