Image display using a computer system, including, but not limited to, display of a reference image for comparison with a current image in image editing

A computer-implemented method for image processing, each image being represented by digital data, the method comprising:

• (1) obtaining, by a computer system, first-image data which are digital data representing a first image;
• (2) the computer system receiving editing commands, and editing the first image in response to the editing commands, wherein editing of each image comprises editing the digital data representing the image, and the first image is edited to obtain one or more second images from the first image, each second image being represented by associated digital data defined by the first-image data and the editing commands, each second image being associated with those one or more of the editing commands which were executed to obtain the second image from the first image;
• (3) after obtaining the first and second images, the computer system receiving a display command via a human-user interface to display a reference image relative to a current image, wherein the reference image is one of the first and second images, and the current image is one of the one or more second images, the reference image being different in size and/or orientation from the current image, the display command identifying the reference image but not a size and orientation with which the second image is to be displayed;
• (4) in response to the display command:
• (4A) the computer system using one or more predefined types of operations to select, from the editing commands, each editing command involving any one of the one or more predefined types of operations,
• wherein the one or more predefined types of operations include any type that modifies the size of at least one element of an image on which the operation is to be performed without removing the element from the image,
• wherein the one or more predefined types include any type that modifies the orientation of the image on which the operation is to be performed,
• wherein the one or more predefined types of operations do not include at least one type of color modification in the image on which the operation is to be performed,
• the computer system deriving, from each selected editing command but not from any deselected editing command, and from the data representing one or more of the first and second images, a processed image which is to be displayed in response to the display command;
• and
• (4B) the computer system displaying the processed image.

A non-transitory computer-readable medium comprising one or more computer-readable computer instructions for causing a computer system to perform a method for image processing, the method comprising:

• (1) providing, by the computer system, a first image to a computer display system, the first image being defined by digital data;
• (2) receiving, by the computer system, a display command to display a second image which is defined by digital data, wherein the first image was obtained by editing the second image and/or the first and second images were obtained by editing a common image which is defined by digital data,
• wherein editing of each image comprises editing digital data representing the image in response to one or more editing commands;
• and
• (3) in response to the display command, processing, by the computer system, the second image to obtain a processed image defined by digital data, and providing the processed image to the computer display system;
• (4) wherein the processing comprises:
• (4A) the computer system determining if the editing commands comprise any command involving any one of one or more predefined types of operations;
• wherein the one or more predefined types of operations do not include at least one type of color modification in an image on which the operation is to be performed;
• (4B) if the editing commands comprise any command involving any predefined type of operations, the computer system deriving the processed image from each editing command involving any predefined type of operations but not from any other editing command, and from the digital data representing the second image;
• wherein at least one of the following statements (i), (ii), (iii) (iv) is true:
• (i) the one or more predefined types of operations include any type that modifies the size of at least one element of an image on which the operation is to be performed without removing the element from the image;
• and
• if at least one element of the processed image which corresponds to an element of the first image is different in size than the corresponding element of the first image, then operation (3) comprises re-sizing the second image to obtain the processed image so that each element of the processed image which corresponds to an element of the first image is displayed with the same size as the element of the first image;
• and/or
• (ii) the one or more predefined types of operations include any type that modifies the orientation of an image on which the operation is to be performed;
• and
• if the first and second images have different orientations, then the processed image has the same orientation as the first image;
• and/or
• (iii) the one or more predefined types of operations include at least one type that trims away a portion of an image on which the operation is to be performed;
• and
• if a portion was trimmed away from the first image in execution of one or more commands of said type that trims away a portion, then the second image is processed to trim away a portion which corresponds to the portion trimmed away from the first image;
• and/or
• (iv) the one or more predefined types of operations include at least one type that combines an image on which the operation is to be performed with another image;
• and
• if the first image was created using an operation of said type that combines an image with another image, which operation involved combining with a third image, then the second image is processed to perform combining with the third image to obtain the processed image.