Abstract: A method is provided for decoding a bit stream representing an image that has been encoded The method includes the steps of: performing an entropy decoding of the bit stream to form a plurality of transform coefficients and a plurality of motion vectors; performing an inverse transformation on the plurality of transform coefficients to form a plurality of error blocks; determining a plurality of predicted blocks based on bidirectional motion estimation that employs the motion vectors, wherein the bidirectional motion estimation includes a direct prediction mode and a second prediction mode; and, adding the plurality of error blocks to the plurality of predicted blocks to form the image. The second prediction mode may include forward, backward, and interpolated prediction modes.

Abstract: A rate control system is disclosed for video coding applications. The rate controller assigns a quantization parameter for video data in a picture in response to complexity indicators indicative of spatial complexity, motion complexity and/or bits per pel of the picture. A virtual buffer based quantizer parameter is proposed based on a virtual buffer fullness analysis and a target rate estimate, which is derived from the complexity indicators. A second quantizer parameter is proposed from a linear regression analysis of quantizer parameters used to code previously coded pictures of similar type (e.g., I pictures, P pictures or B pictures). A coding policy decision unit defines a final quantizer parameter from a comparison of the two proposed quantizer parameters.

Abstract: A method of decoding, composing and rendering a scene. First information is obtained, the first information including a part of a MPEG-4 BIFS scene description stream and at least one coded MPEG-4 media stream. The first information is decoded by invoking a BIFS scene decoder and one or more specific media decoders that are required by the scene. Second information is obtained, the second information including a second part of a BIFS scene description stream that contains a reference to an external application. The second information is decoded by invoking the BIFS scene decoder and an external application decoder. An integrated scene is composed, the integrated scene including one or more decoded MPEG-4 media objects and one or more external application objects specified in the decoded scene descriptions streams. The composed integrated scene is rendered on a display.

Abstract: A method, computer program product, and computing device for modifying a first channel portion of a digital media data file to include at least a first primary watermark. A second channel portion of the digital media data file is modified to include at least a first secondary watermark, wherein the first secondary watermark is the complement of the first primary watermark.

Abstract: The invention provides a system and method for integrating multimedia descriptions in a way that allows humans, software components or devices to easily identify, represent, manage, retrieve, and categorize the multimedia content. In this manner, a user who may be interested in locating a specific piece of multimedia content from a database, Internet, or broadcast media, for example, may search for and find the multimedia content. In this regard, the invention provides a system and method that receives multimedia content and separates the multimedia content into separate components which are assigned to multimedia categories, such as image, video, audio, synthetic and text. Within each of the multimedia categories, the multimedia content is classified and descriptions of the multimedia content are generated. The descriptions are then formatted, integrated, using a multimedia integration description scheme, and the multimedia integration description is generated for the multimedia content.

Abstract: A method, computer program product, and computing device for obtaining an uncompressed digital media data file. One or more default watermarks is inserted into the uncompressed digital media data file to form a watermarked uncompressed digital media data file. The watermarked uncompressed digital media data file is compressed to form a first watermarked compressed digital media data file. The first watermarked compressed media data file is stored on a storage device. The first watermarked compressed media data file is retrieved from the storage device. The first watermarked compressed digital media data file is modified to associate the first watermarked compressed digital media data file with a transaction identifier to form a second watermarked compressed digital media data file.

Abstract: A rate control system is disclosed for video coding applications. The rate controller assigns a quantization parameter for video data in a picture in response to complexity indicators indicative of spatial complexity, motion complexity and/or bits per pel of the picture. A virtual buffer based quantizer parameter is proposed based on a virtual buffer fullness analysis and a target rate estimate, which is derived from the complexity indicators. A second quantizer parameter is proposed from a linear regression analysis of quantizer parameters used to code previously coded pictures of similar type (e.g., I pictures, P pictures or B pictures). A coding policy decision unit defines a final quantizer parameter from a comparison of the two proposed quantizer parameters.

Abstract: A video coding system that codes video objects as scalable video object layers. Data of each video object may be segregated into one or more layers. A base layer contains sufficient information to decode a basic representation of the video object. Enhancement layers contain supplementary data regarding the video object that, if decoded, enhance the basic representation obtained from the base layer. The present invention thus provides a coding scheme suitable for use with decoders of varying processing power. A simple decoder may decode only the base layer of video objects to obtain the basic representation. However, more powerful decoders may decode the base layer data of video objects and additional enhancement layer data to obtain improved decoded output. The coding scheme supports enhancement of both the spatial resolution and the temporal resolution of video objects.

Abstract: A method and apparatus for performing motion estimation in a digital video system is disclosed. Specifically, the present invention discloses a system that quickly calculates estimated motion vectors in a very efficient manner. In one embodiment, a first multiplicand is determined by multiplying a first display time difference between a first video picture and a second video picture by a power of two scale value. This step scales up a numerator for a ratio. Next, the system determines a scaled ratio by dividing that scaled numerator by a second first display time difference between said second video picture and a third video picture. The scaled ratio is then stored calculating motion vector estimations. By storing the scaled ratio, all the estimated motion vectors can be calculated quickly with good precision since the scaled ratio saves significant bits and reducing the scale is preformed by simple shifts.

Abstract: A method and apparatus for performing motion estimation in a digital video system is disclosed. Specifically, the present invention discloses a system that quickly calculates estimated motion vectors in a very efficient manner. In one embodiment, a first multiplicand is determined by multiplying a first display time difference between a first video picture and a second video picture by a power of two scale value. This step scales up a numerator for a ratio. Next, the system determines a scaled ratio by dividing that scaled numerator by a second first display time difference between said second video picture and a third video picture. The scaled ratio is then stored calculating motion vector estimations. By storing the scaled ratio, all the estimated motion vectors can be calculated quickly with good precision since the scaled ratio saves significant bits and reducing the scale is performed by simple shifts.

Abstract: A method is provided for decoding a bit stream representing an image that has been encoded The method includes the steps of: performing an entropy decoding of the bit stream to form a plurality of transform coefficents and a plurality of motion vectors; performing an inverse transformation on the plurality of transform coefficients to form a plurality of error blocks; determining a plurality of predicted blocks based on bidirectional motion estimation that employs the motion vectors, wherein the bidirectional motion estimation includes a direct prediction mode and a second prediction mode; and, adding the plurality of error blocks to the plurality of predicted blocks to form the image. The second prediction mode may include forward, backward, and interpolated prediction modes.

Abstract: A method of decoding, composing and rendering a scene. First information is obtained, the first information including a part of a MPEG-4 BIFS scene description stream and at least one coded MPEG-4 media stream. The first information is decoded by invoking a BIFS scene decoder and one or more specific media decoders that are required by the scene. Second information is obtained, the second information including a second part of a BIFS scene description stream that contains a reference to an external application. The second information is decoded by invoking the BIFS scene decoder and an external application decoder. An integrated scene is composed, the integrated scene including one or more decoded MPEG-4 media objects and one or more external application objects specified in the decoded scene descriptions streams. The composed integrated scene is rendered on a display.

Abstract: A video coding system that codes video objects as scalable video object layers. Data of each video object may be segregated into one or more layers. A base layer contains sufficient information to decode a basic representation of the video object. Enhancement layers contain supplementary data regarding the video object that, if decoded, enhance the basic representation obtained from the base layer. The present invention thus provides a coding scheme suitable for use with decoders of varying processing power. A single decoder may decode only the base layer of video objects to obtain the basic representation. However, more powerful decoders may decode the base layer data of video objects and additional enhancement layer data to obtain improved decoded output. The coding scheme supports enhancement of both the spatial resolution and the temporal resolution of video objects.

Abstract: A rate control system is disclosed for video coding applications. The rate controller assigns a quantization parameter for video data in a picture in response to complexity indicators indicative of spatial complexity, motion complexity and/or bits per pel of the picture. A virtual buffer based quantizer parameter is proposed based on a virtual buffer fullness analysis and a target rate estimate, which is derived from the complexity indicators. A second quantizer parameter is proposed from a linear regression analysis of quantizer parameters used to code previously coded pictures of similar type (e.g., I pictures, P pictures or B pictures). A coding policy decision unit defines a final quantizer parameter from a comparison of the two proposed quantizer parameters.

Abstract: File formats systems and methods are disclosed that provide a framework that integrates concepts, such as objects based audio-visual representation, meta-data and object oriented programming, to achieve a flexible and generic representation of the audiovisual information and the associated methods to operate on the audiovisual information. A system and method are disclosed for storing data processed from presentation data. The data is stored according to a method comprising coding input presentation data by identifying objects from within the presentation data, coding each object individually and organizing the coded data into access layer data units. The access layer data units are stored throughout a plurality of segments, each segment comprising a segment table in a header portion thereof and those access layer data units that are members of the respective segment, there being one entry in the segment table for each access layer data unit therein.

Abstract: File formats systems and methods are disclosed that provide a framework that integrates concepts, such as objects based audio-visual representation, meta-data and object oriented programming, to achieve a flexible and generic representation of the audiovisual information and the associated methods to operate on the audiovisual information. A system and method are disclosed for storing data processed from presentation data. The data is stored according to a method comprising coding input presentation data by identifying objects from within the presentation data, coding each object individually and organizing the coded data into access layer data units. The access layer data units are stored throughout a plurality of segments, each segment comprising a segment table in a header portion thereof and those access layer data units that are members of the respective segment, there being one entry in the segment table for each access layer data unit therein.

Abstract: A method is provided for decoding a bit stream representing an image that has been encoded. The method includes the steps of: performing an entropy decoding of the bit stream to form a plurality of transform coefficients and a plurality of motion vectors; performing an inverse transformation on the plurality of transform coefficients to form a plurality of error blocks; determining a plurality of predicted blocks based on bidirectional motion estimation that employs the motion vectors, wherein the bidirectional motion estimation includes a direct prediction mode and a second prediction mode; and, adding the plurality of error blocks to the plurality of predicted blocks to form the image. The second prediction mode may include forward, backward, and interpolated prediction modes.

Abstract: A method and apparatus for performing motion estimation in a digital video system is disclosed. Specifically, the present invention discloses a system that quickly calculates estimated motion vectors in a very efficient manner. In one embodiment, a first multiplicand is determined by multiplying a first display time difference between a first video picture and a second video picture by a power of two scale value. This step scales up a numerator for a ratio. Next, the system determines a scaled ratio by dividing that scaled numerator by a second first display time difference between said second video picture and a third video picture. The scaled ratio is then stored calculating motion vector estimations. By storing the scaled ratio, all the estimated motion vectors can be calculated quickly with good precision since the scaled ratio saves significant bits and reducing the scale is performed by simple shifts.

Abstract: Methods for processing a set of successive video frames in two passes to determine the number of bidirectional (B) and unidirectional (P) motion compensated frames to be encoded in a video coding system. During the first pass, motion vectors and motion costs are computed for each frame and a derived cost value is computed based on the motion cost of at least one frame. The derived cost value is used to determine the number (NB) of B-frames to be encoded in the set of successive frames. In the second pass, the set of successive frames are encoded where NB frames are encoded as B-frames and some or all motion vectors computed in the first pass are re-used in the second pass. A scene cut detection method is also provided where an impulse-like increase in a ratio of motion costs is monitored.

Abstract: A method and apparatus for performing motion estimation in a digital video system is disclosed. Specifically, the present invention discloses a system that quickly calculates estimated motion vectors in a very efficient manner. In one embodiment, a first multiplicand is determined by multiplying a first display time difference between a first video picture and a second video picture by a power of two scale value. This step scales up a numerator for a ratio. Next, the system determines a scaled ratio by dividing that scaled numerator by a second first display time difference between said second video picture and a third video picture. The scaled ratio is then stored calculating motion vector estimations. By storing the scaled ratio, all the estimated motion vectors can be calculated quickly with good precision since the scaled ratio saves significant bits and reducing the scale is performed by simple shifts.