Showing papers on "Alpha compositing published in 2001"

Alpha channel estimation in high resolution images and image sequences

Abstract: For motion picture special effects, it is often necessary to take a source image of an actor, segment the actor from the unwanted background, and then composite over a new background. The standard approach requires the unwanted background to be a blue screen. While this technique is capable of handling areas where the foreground blends into the background, the physical requirements present many practical problems. This paper presents an algorithm that requires minimal human interaction to segment motion picture resolution images and image sequences. We show that it can be used not only to segment badly lit or noisy blue screen images, but also to segment actors where the background is more varied.

Image composizing device, recorded medium, and program

Abstract: An image compositing apparatus of the present invention composites a video image and a plurality of graphical images together into a final composite image. The image compositing apparatus includes a first obtaining unit, a first compositing unit, a calculating unit, a second obtaining unit, and a second compositing unit. The first obtaining unit obtains the graphical images and composition information that includes an image compositing order and is used for calculating the composition ratios of the images to the final composite image. The first compositing unit composites the graphical images together into one composite graphical image according to the composition information. The calculating unit calculates the composition ratio of the video image to the final composite image according to the composition information. The second obtaining unit obtains frames of the video image. The second compositing unit composites the frames with the composite graphical image using the composition ratio of the video image.

Digital camera and method for compositing images

Abstract: The digital camera includes an image pickup unit, an image storing unit, an image display unit, a reference image designating unit with which one or more of at least partial areas of an image to be referenced for image compositing are designated as a reference image area and an image compositing unit which produces a composite image such that a reference image within the reference image area is displayed as superposed on an image being presently photographed. The image processing method attaches first identification information to one or more of at least partial areas of the specified image and designated area information upon photographing, attaches second identification information to an image in an shooting frame to be composited with the reference image and prepares image data for a composite image obtained by compositing the image with the reference image based on the first and second identification information as well as the designated area information.

Selecting objects with freehand sketches

Abstract: We present in this paper the design of an interactive tool for selecting objects using simple freehand sketches The objective is to extract object boundaries precisely while requiring little skill and time from the user The tool proposed achieves this objective by integrating user input and image computation in a two-phase algorithm In the first phase, the input sketch is used along with a coarse global segmentation of the image to derive an initial selection and a triangulation of the region around the boundary The triangles are used to formulate subproblems of local finer-grained segmentation and selection Each of the subproblems is processed independently in the second phase, where a linear approximation of the local boundary as well as a local, finer-grained segmentation are computed The approximate boundary is then used with the local segmentation to compute a final selection, represented with an alpha channel to fully capture diffused object boundaries Experimental results show that the tool allows very simple sketches to be used to select objects with complex boundaries Therefore, the tool has immediate applications in graphics systems for image editing, manipulation, synthesis, retrieval and processing

Digital camera and image processing method

Abstract: The digital camera includes an image pickup unit, an image storing unit, an image display unit, a reference image designating unit with which one or more of at least partial areas of an image to be referenced for image compositing are designated as a reference image area and an image compositing unit which produces a composite image such that a reference image within the reference image area is displayed as superposed on an image being presently photographed. The image processing method attaches first identification information to one or more of at least partial areas of the specified image and designated area information upon photographing, attaches second identification information to an image in an shooting frame to be composited with the reference image and prepares image data for a composite image obtained by compositing the image with the reference image based on the first and second identification information as well as the designated area information.

Image compositing device, recording medium, and program

Abstract: An image compositing apparatus of the present invention composites a video image and a plurality of graphical images together into a final composite image. The image compositing apparatus includes a first obtaining unit, a first compositing unit, a calculating unit, a second obtaining unit, and a second compositing unit. The first obtaining unit obtains the graphical images and composition information that includes an image compositing order and is used for calculating the composition ratios of the images to the final composite image. The first compositing unit composites the graphical images together into one composite graphical image according to the composition information. The calculating unit calculates the composition ratio of the video image to the final composite image according to the composition information. The second obtaining unit obtains frames of the video image. The second compositing unit composites the frames with the composite graphical image using the composition ratio of the video image.

System and method for compositing of two or more real images in a cinematographic puppetry production

Abstract: An improved cinematographic system and method for multiple compositing, within a virtual studio, of an image frame or image sequence of a real/action image of an action sequence of a puppet, with another image frame or image sequence of a real/action image of the same or another puppet, within a given virtual studio space. This system and method have application to the compositing of a master camera angle image and a close-up image of the same puppet character; and, to the compositing of a master camera angle image of one action puppet character with a second image from another camera angle of another puppet action character, so as to provide an interactive image sequence of each of the characters of each image within the same image frame.

Systems and methods for applying 8-bit alpha blending to bitonal images

Abstract: Systems and methods are described for applying 8-bit alpha blending to a bitonal source image and a bitonal destination image to produce a bitonal blended image. The bitonal blended image has a high quality, but memory resources are preserved because the process is accomplished without expanding the 1-bit images to 8-bit space before generating the blended image.

Rendering volumetric fog and other gaseous phenomena using an alpha channel

Abstract: A system, method, and computer program product for rendering gaseous volumetric objects scenes using an alpha channel. In one described implementation, the method determines a distance between a user to boundaries of a gaseous volume and then stores the distance in an alpha channel to arrive at an alpha value. Then the alpha value can be used as a factor assist in blending scene colors with gaseous colors to render virtually realistic pixels for the gaseous object from the perspective of a user's view of the object. The resulting scenes can then be used to simulate patchy fog, clouds, or other gases of more or less constant density and color.

Image synthesizing device, recorded medium, and program

Abstract: An image synthesizing device (100) for synthesizing an image by combining a time-varying image and still image, comprising first acquiring means (103) for acquiring synthesization information including the image combining order for determining the combination ratios of the images before the synthesization to the synthesized image and acquiring the still images, first synthesizing means (108) for combining the still images according to the synthesization information to create a synthesized still image, calculating means (109) for determining the combination ratio of the time-varying image to the synthesized image according to the synthesization information, second acquiring means (105) for acquiring each frame constituting the time-varying image, and second synthesizing means (110) for combining the frames and the synthesized still image at the combination ratio of the time-varying image, whereby a synthesized image is created in real time in accordance with the reproduction rate of the time-varying image.

Alpha-channel compositing system

Abstract: A compositing system ( 300 ) that comprises an optimized alpha-channel compositing module ( 303 ) is disclosed. The compositing system ( 300 ) optimizes the range correction in the alpha-channel compositing module ( 303 ) by using a constant divider ( 401 ) and delaying the correction of an alpha value until after the summation of the alpha values from all contributing regions. Uncorrected opacity values are used to index a look-up table in order to reduce the data processing path to a multiplier ( 407 ) for processing after premultiplication of a color values from all contributing regions.

Device and method for compositing images and program

Abstract: PROBLEM TO BE SOLVED: To provide an image compositing device for obtaining an image equivalent to an image obtained by zooming during the exposure by segmenting a plurality of images with different magnification from one piece of image data and compositing the plurality of images. SOLUTION: In a recording mode, an image fetched by a CCD 1 is sent to a YUV processor 3 to be subjected to color process processing, and image data are sent to an image memory 4 via a memory controller 5. A through image is simultaneously displayed. If it is in a composite zoom photographing mode here, a plurality of images are prepared by zooming the image data obtained at the moment a shutter is pressed down and stored in the image memory 4 as an original image to a plurality of stages. A composite zoom image equivalent to an image obtained be zooming during the exposure is prepared by compositing the plurality of the images.

Print controller, drawing controller, data processing method and storage medium

Abstract: If a drawing section does not support the alpha blending drawing, or the bit depth of a first bitmap image is less than that of the alpha blending value, the alpha blending drawing is unavailable. To solve the problem even in such cases, a data processing method for a print controller and drawing controller, which is provided with a drawing section for executing drawing according to an input drawing command to a first bitmap image and a drawing process specifying section for performing alpha blending specification (transparency degree specification) for executing drawing according to an input object as a drawing command to the first bitmap image, includes an alpha value replacing section for replacing the alpha blending specification with area information corresponding to an alpha value and a drawing command converting section for converting the drawing command into another drawing command for performing a process corresponding to the area information.

System & method for compositing of two or more real images in a cinematographic puppetry production

Abstract: An improved cinematographic system and method for multiple compositing, within a virtual studio, of an image frame or image sequence of a real/action image of an action sequence of a puppet, with another image frame or image sequence of a real/action image of the same or another puppet, within a given virtual studio space. This system and method have application to the compositing of a master camera angle image and a close-up image of the same puppet character; and, to the compositing of a master camera angle image of one action puppet character with a second image from another camera angle of another puppet action character, so as to provide an interactive image sequence of each of the characters of each image within the same image frame.

Image compositing apparatus

Abstract: PROBLEM TO BE SOLVED: To speedily and exactly perform a diagnosis based on a thermal image. SOLUTION: This image compositing apparatus is provided with a pair of right and left infrared cameras, a pair of right and left visible cameras, and a first image compositing processing means for performing compositing processing of data outputted from the right and left infrared cameras and data outputted from the right and left visible cameras so that an observer can watch a three-dimensional(3D) thermal image and a 3D visible image in the state of overlapping these images.

Algorithms for the Multilayer Overlay in Video Effect

Abstract: The concept of Alpha channel is summarized in detail. Formulas for multilayer overlay composition of video objects are deduced and verified with Adobe After Effects software, the meaning of premultiplied color composition is presented. By proving that the filtering operation of video object in single layer is carried out on premultiplied color, its rotation and zooming operations should be carried out on premultiplied color too. It comes out, not the non-premultiplied color, but the premultiplied color should be stored in the frame buffer.

Rendering system using sample images

Abstract: A system for rendering a multiplicity of dynamic three-dimensional objects in a virtual environment, the system comprising a memory for storing a plurality of sample images representing the objects viewed from different angles, the system further comprising processing means configured for: for each object to be displayed, selecting a sample image from the memory based on the angle of viewing the object, wherein the pixels of the sample image include an alpha channel value for identifying a plurality of different regions of the image; mapping the sample image to a polygon representing the location of the object in the environment, including performing multi-pass rendering of the sample image, wherein each pass is for rendering differently coloured regions of the sample image identified by the alpha channel values.

Alpha channel filter

Abstract: An image processing filter processes an image, and the resultant processed image is merged with an unprocessed version of the image using an alpha channel. The ability to modify the alpha channel based on user input is provided, and the image is reprocessed upon the alpha channel being modified. It is possible for image processing filters to be painted on to an image. The paint layer system takes into consideration how much paint has been applied to the pixel being processed. The simplest form of the invention, which can be expressed as ProcessedPixel=SourcePixel+AlphaPixel, results in each pixel in the image being brightened by an amount relative to the spatially equivalent alpha channel pixel.