Re-sizing image sequences
AssigneeSnell & Wilcox Limited
InventorMichael James Knee
Life of this patent
Estimating the term…
Abstract
To modify the aspect ratio of images in a video sequence, a measure of image energy is provided at or around each pixel, for example by taking differences between adjacent pixels. A minimum energy path of contiguous pixels is then identified which extends across the image from one edge to another, for example vertically if the width of the picture is to be modified. Information concerning the location of a path in one image is used in the identification of a path in the next image, for example by biassing the energy measure of the path. The aspect ratio of each image is then modified by removing or by replicating the minimum energy path of contiguous pixels.
Claims31
A method in an image processor of changing the size of a first image, forming part of a sequence of images, comprising the steps of selecting a low spatial-frequency-energy region in the first image;
- and removing or enlarging the selected low spatial-frequency-energy region in the first image, wherein the selection of the region in the first image to be removed or enlarged is biassed towards the position of a low spatial-frequency-energy region in a second image in the sequence.
A method in an image processor of changing the size of an image comprising the steps of processing a set of pixels that represent the image so as to find a low spatial-frequency-energy path between points on opposite edges of the image comprising a sub-set of the said set of pixels;
- evaluating the total spatial-frequency energy of the said sub-set of pixels;
- using the evaluated total spatial-frequency energy of the said sub-set pixels to determine the magnitude of a one-dimensional expansion or contraction;
- and applying said expansion or contraction to those parts of the said image that lie on the said path.
A method in an image processor of processing a sequence of pixel based images to modify the aspect ratio of the images, comprising the steps of providing at or around each pixel a measure of image energy;
- identifying for each image a low energy path of contiguous pixels extending across the image from one edge of the image to a different edge of the image, wherein information concerning the location of a path in one image is used in the identification of a path in the next image of the sequence;
- and modifying the aspect ratio of each image by removing or by replicating said low energy path of contiguous pixels.
(canceled)
A computer software product including instructions for implementing a method comprising the steps of providing at or around each pixel a measure of image energy;
- identifying for each image a low energy path of contiguous pixels extending across the image from one edge of the image to a different edge of the image, wherein information concerning the location of a path in one image is used in the identification of a path in the next image of the sequence;
- and modifying the aspect ratio of each image by removing or by replicating said low energy path of contiguous pixels.
Dependencies are inferred from the claim text.