Canon Kabushiki Kaisha

Canon Information Systems Research Australia Pty. Ltd.

Canon Inc.

Other

Timothy Merrick Long

George Politis

Christopher Amies

Kevin John Moore

Christopher Fraser

Ian Richard Gibson

Michael John Webb

Paul Quentin Scott

Martin Paul Tlaskal

Marija Herceg

James Philip Andrew

Peter Alleine Fletcher

Stephen James Hardy

Cameron Bolitho Browne

Axel Lakus-Becker

James Robert Metcalfe

Stephen Edward Ecob

Andrew Timothy Robert Newman

Ka-Ming Leung

Scott Bradley

Graham Stoney

Kok Tjoan Lie

Gerard Anthony Hill

James David Clark

Nicolas Leslie Coleman

Peter Leslie Bell

Lincoln David Stone

Jeremy D M Thorp

Richard M Antill

Benjamin Michael Lever

Andrew Timothy Newman

A method () of performing distributed video encoding on an input video frame (), is disclosed. The method () forms a bit-stream from original pixel values of the input video frame (), such that groups of bits in the bit-stream are associated with clusters of spatial pixel positions in the input video frame (). The bit-stream is interleaved to reduce the clustering. The interleaved bit-stream is encoded to generate parity bits from the bit-stream according to a bitwise error correction method.

For error correction in distributed video coding

A method determines a color at a plurality of locations in a region of overlap of a first graphic element and a second graphic element, with each graphic element having a color value and a partial opacity value defined at each location. The method includes the steps of determining a transfer color as a combination of the color value of the first graphic element and the color value of the second graphic element, with the transfer color being independent of the opacity values of each element, and determining a first color value of a set of possible color values. At least one color value in the set of possible color values is derived from the transfer color, and another color value in the set of possible color values is derived from the color value of at least one of the first graphical element and the second graphical element. Additional steps include selecting the first color value from the set of possible color values to determine the color at a first selected location in the region of overlap, and determining a second color value from the set of possible color values, and selecting the second color value for a second selected location in the region of overlap. The selection of the first and second color values is at least dependent upon the partial opacity value of the first or second graphical elements.

Simplification of alpha compositing in the presence of transfer functions

An anti-tampering method for processing documents is disclosed. The method comprises, in regard to an encoding step, the steps of resolving (in a step) in regard to an N-level image to be recorded, a pixel of the image into a major component having N possible values, selecting (in the step) a pattern element depending upon the major component and the position of the pixel in the image, and recording the selected pattern element (in a step) onto a transfer medium. In regard to a corresponding decoding step the method comprises extracting (in a step) from the recorded document, a retrieved pattern element for said pixel, determining a pattern element (in a step) depending upon a major component extracted from the retrieved pattern element and the position of the pixel on the recorded document, and comparing (in a step) the retrieved pattern element and the said determined pattern element.

Secure recorded documents

A method of rendering a scan line of a graphic object image in a scan line renderer for spans of pixels laying between consecutive x-ordered edges intersecting the scan line includes maintaining a set of depths present in the rendering of the scan line, with the set being maintained in depth order. For each span, the set contains at least those depths that are active in the span, and the set is subject to removal of at least one depth at a subsequent span on the scan line where the corresponding depth is no longer active.

Method for tracking depths in a scanline based raster image processor

In rendering a page description on a rendering system, a method comprises the step of receiving objects and generating one or more sets of render instructions. For each received object it is first determined whether by adding the corresponding render instructions of a current received object to a current set of render instructions the resources of the rendering system will be exceeded. If the resources would be exceeded then a new set of render instructions are created, render instructions are added thereto to draw the current set of render instructions as a background image, and then the corresponding render instructions of the current received object are added to the new set. On the other hand, if the resources would not be exceeded then the corresponding render instructions of the current received object are added to the current set. Finally, the method renders the one or more sets of rendering instructions.

Rendering page descriptions

Disclosed are methods, apparatus () and computer readable media for rendering at least one graphic object () described by at least one edge (--) into a raster pixel image () having a plurality of scan lines and a plurality of pixel locations on each scan line. For each scan line, coordinates of intersection of those edges of the objects that intersect the scan line are determined in a predetermined order. This is preferably achieved by processing edge records () using a number of buffers () thereby enabling efficient sorting of edge intersections into order. For each adjacent pair of edge intersections, information () associated with the corresponding object is examined to determining a set of active objects () for a span of pixel locations between the corresponding pair of edge intersections. For each span of pixel locations, the corresponding set of active objects is used to determine () a value for each of the locations within the span. The information may include one or more of a fill count, a clip count and other factors. A compositing model accommodating opacity is also disclosed, as are stack operations used to facilitate rendering and other features which contribute to fast processing of image components.

Processing graphic objects for fast rasterised rendering

The method combines a plurality of images. The images each have associated meta-data comprising meta-data element(s) having merging attribute tag(s). The merging attribute describes an action to be taken with the corresponding meta-data element when the images are combined. The method first reads () the attribute(s) of the images to identify the action(s) and then combines the meta-data elements of the images in accordance with said action(s) In another embodiment, the method transforms an image.

Combining a plurality of images and transforming an image having associated meta-data

A method of creating a series of font characters () on a computer system () is disclosed. A series of font outlines () and source artwork (); a series of manipulation tools () for the manipulation of aspects of the outlines and artwork. Such an arrangement provides for the creation of substantially arbitrarily complex font structures from the outlines, artwork and manipulation tools. A series of font characters is then formed through the application of the complex font structures to each of a base font outline in the series of font characters. Preferably, the complex font structures can comprise a graphical expression tree of operations () to be performed in the creation of a font and the tree includes an outline of a font character. The manipulation tools can include tools for distorting, replacing or compositing the outline of a font and can further include the tools for the application of morphological and non-morphological effects to the font outlines. A data structure for such font creation is also disclosed which includes records () of attributes of glyphs used to form the outlines including their shape, color, opacity and where appropriate compositing or blending with graphic object or pixel-based images.

Font architecture and creation tool for producing richer text

Disclosed are methods, apparatus ( ) and computer readable media for rendering at least one graphic object ( ) described by at least one edge ( ) into a raster pixel image ( ) having a plurality of scan lines and a plurality of pixel locations on each scan line. For each scan line, coordinates of intersection of those edges of the objects that intersect the scan line are determined in a predetermined order. This is preferably achieved by processing edge records ( ) using a number of buffers ( ) thereby enabling efficient sorting of edge intersections into order. For each adjacent pair of edge intersections, information ( ) associated with the corresponding object is examined to determining a set of active objects ( ) for a span of pixel locations between the corresponding pair of edge intersections. For each span of pixel locations, the corresponding set of active objects is used to determine ( ) a value for each of the locations within the span. The information may include one or more of a fill count, a clip count and other factors. A compositing model accommodating opacity is also disclosed, as are stack operations used to facilitate rendering and other features which contribute to fast processing of image components.

Fast rendering techniques for rasterised graphic object based images

A method and apparatus for creating an image is disclosed. The image is formed by rendering at least a plurality of graphical objects to be composited according to a compositing expression. Each object has a predetermined outline. The method comprises the following steps. Firstly, dividing a space in which the outlines are defined into a plurality of mutually exclusive regions wherein each of the regions is defined by a region outline substantially following at least one of the predetermined outlines or parts thereof. Secondly, examining each of the regions to determine those objects which contribute to the regions. Thirdly, modifying the compositing expression on the basis of the contribution of each of the objects within the region to form an optimised compositing expression for each region. Fourthly, compositing the image using each of the optimised compositing expressions.

Optimising image compositing

A method and apparatus for creating an image is disclosed. The image is formed by rendering at least a plurality of graphical objects to be composited according to a compositing expression. Each object has a predetermined outline. The method comprises the following steps. Firstly, dividing a space in which the outlines are defined into a plurality of mutually exclusive regions wherein each of the regions is defined by a region outline substantially following at least one of the predetermined outlines or parts thereof. Secondly, examining each of the regions to determine those objects which contribute to the regions. Thirdly, modifying the compositing expression on the basis of the contribution of each of the objects within the region to form an optimized compositing expression for each region. Fourthly, compositing the image using each of the optimized compositing expressions.

Optimizing image compositing

The present invention discloses apparatus for, and a method of, rendering image data prior to outputting of the resulting image. A graphics co-processor ( ) is utilized together with a host CPU ( ), the former having a plurality of data calculation streams ( ) arranged in parallel fashion. Only one of the data calculation streams ( ) is operated at any one time. Preferably at least one ( ) of the data calculation streams is able to be reconfigured.

Multi-instruction stream processor

An apparatus includes a DCT unit for transforming blocks of pixels into respective blocks of transform coefficients, entropy encoders for encoding respective partitions of the DCT blocks where at least one partition comprises bit-plane data from each block of transform coefficients, and a scan output manager for storing the entropy encoded partitions in a buffer of fixed memory size. The manager manages the storing of the coded partitions in the buffer whereby during the storing of the coded partitions if it is determined the buffer is full, a coded least perceptually significant partition currently stored in the buffer is overwritten by data from a coded more perceptually significant partition.

Storing coding image data in storage of fixed memory size

A method of automatically positioning one or more images within a region. The method comprises of computing ( ) a field at each image due to every other image, wherein the field at any image due to any other image is a function of the distance between any image and any other image and the surface area of that any other image. The method then computates ( ) a net force exerted on each image by every other image, wherein the net force acting on any one image is a function of the field acting on the said any one image and a characteristic of the said any one image. The method then moves ( ) each image a distance, which is a function of the net force acting on the image, in the direction of the net force.

Method and apparatus for automatically positioning images within a region

A method and apparatus manipulates thumbnail images as used in image-based browsing file management systems. Zooming in and out of thumbnail images can be performed without a continued need to decompress a true image thus providing for faster operation. Pixel interpolation and/or replication are used to generate intermediate images that are displayed to deliver to the user a perception of a transitory zoom yet are of sufficient detail to maintain user orientation. Aspect ratio zooming of thumbnail containment areas is also disclosed which facilitates ease of browsing. The compression of thumbnail type images using a discrete wavelet transform facilitates the fast zoom of thumbnails and their associated containment areas.

Growing community of inventors

Lindfield, Australia

Timothy Merrick Long