Abstract: Techniques of audio-video synchronization that can be performed on audio and video streams are described. In one scenario, a processor can receive audio-video information comprising a video stream and an audio stream. Each of the video and audio streams can include one or more of: a compressed stream; and a decoded stream. A region of motion in the video stream can be determined based on a property of the video stream. A video signal can be generated based on the determined region of motion. Also, a relative delay between the streams can be determined based, at least in part, on the generated video signal. A delay value associated with one or more of the audio and video streams may be adjusted to assist with synchronizing the audio and video streams.

Abstract: A system includes a network interface for sending and receiving at least video data between two or more endpoints, where each endpoint includes a display screen. A camera may be located at more than one endpoint capturing video data. The system also includes a control unit for controlling spatial arrangement of one or more video data streams displayed on a display screen of one or more endpoints. The control unit determines a state and configuration of a videoconference and accesses a route description corresponding to the state and configuration of the videoconference. The route description includes a video data stream destination, one or more video data stream sources, and layout information determining the spatial arrangement of one or more video data streams displayed on the video data stream destination.

Abstract: A system includes a network interface for sending and receiving at least video data between two or more endpoints, where each endpoint includes a display screen. A camera may be located at more than one endpoint capturing video data. The system also includes a control unit for controlling spatial arrangement of one or more video data streams displayed on a display screen of one or more endpoints. The control unit determines a state and configuration of a videoconference and accesses a route description corresponding to the state and configuration of the videoconference. The route description includes a video data stream destination, one or more video data stream sources, and layout information determining the spatial arrangement of one or more video data streams displayed on the video data stream destination.

Abstract: A computer-controlled apparatus and method for fabricating three-dimensional articles in layerwise fashion is disclosed. Upon dispensing a layer of a fusible powder, a laser irradiates selected locations of that layer to fuse the powder into a cross-section of the article to be formed in that layer, such that the fused cross-sections fuse together into the article. The laser is controlled in a raster scan fashion across the selected locations of the powder layer. The parallel raster scan lines are separated from one another, centerline-to-centerline, according to a selected pitch, or fill scan spacing value. The positions of the parallel scan lines are determined with respect to a coordinate system at the powder layer, rather than with respect to boundaries of the cross-section being formed; in alternating layers, the parallel scan lines are offset from one another by one-half the pitch.

Abstract: A computer-controlled apparatus and method for fabricating three-dimensional articles in layerwise fashion is disclosed. Upon dispensing a layer of a fusible powder, a laser irradiates selected locations of that layer to fuse the powder into a cross-section of the article to be formed in that layer, such that the fused cross-sections fuse together into the article. The laser is controlled in a raster scan fashion across the selected locations of the powder layer. The raster scan lines are defined, for each cross-section, to achieve an optimal fill scan time. The optimal fill scan time is determined, by the computer estimating the fill scan time by rotating the cross-section over a plurality of rotational angles, and estimating the fill scan time for each of the rotated cross-sections for at least a sample of the fill scans necessary to form the article.

Abstract: A computer-controlled apparatus and method for fabricating three-dimensional articles in layerwise fashion is disclosed. Upon dispensing a layer of a fusible powder, a laser irradiates selected locations of that layer to fuse the powder into a cross-section of the article to be formed in that layer, such that the fused cross-sections fuse together into the article. The laser is controlled in a raster scan fashion across the selected locations of the powder layer. The raster scan lines are defined, for each cross-section, to achieve an optimal fill scan time. The optimal fill scan time is determined, by the computer estimating the fill scan time by rotating the cross-section over a plurality of rotational angles, and estimating the fill scan time for each of the rotated cross-sections for at least a sample of the fill scans necessary to form the article.

Abstract: A computer-controlled apparatus and method for fabricating three-dimensional articles in layerwise fashion is disclosed. Upon dispensing a layer of a fusible powder, a laser irradiates selected locations of that layer to fuse the powder into a cross-section of the article to be formed in that layer, such that the fused cross-sections fuse together into the article. The laser is controlled in a raster scan fashion across the selected locations of the powder layer. The parallel raster scan lines are separated from one another, centerline-to-centerline, according to a selected pitch, or fill scan spacing value. The positions of the parallel scan lines are determined with respect to a coordinate system at the powder layer, rather than with respect to boundaries of the cross-section being formed; in alternating layers, the parallel scan lines are offset from one another by one-half the pitch.

Abstract: An apparatus and method for producing parts by selective laser sintering are disclosed. The disclosed method selectively sinters a first layer of heat-fusible powder by directing a laser beam so that it scans the first layer in a first direction to sinter a first cross-section of the part. A second layer of the heat-fusible powder is then disposed over the first layer, and the next cross-section of the part is selectively sintered by the laser being scanned in a different direction from the first direction, for example in a direction perpendicular to the first direction. The cross-scanning resulting from scanning in different directions provides parts with structural strength which is not dependent upon orientation, with more uniform surfaces and textures, and with reduced distortion. In addition, each of the layers may have its outlined traced prior to the scanning, to further define the edges of the cross-section.