Abstract: Entropy coding/decoding techniques are disclosed in which data is coded alternately as a series of nonzero values and zero values until the transmitted data is consumed. Nonzero values may be coded first with transmission of data identifying a number of consecutive nonzero values that appear in scan order followed by transmission of the nonzero values themselves. Thereafter, if other data remains to be transmitted, data may be transmitted identifying a number of consecutive zero values that appear next in scan order followed by transmission of a next nonzero value encountered in scan order. By transmitting the nonzero values as a group, it is expected that the proposed entropy-coding process will achieve higher efficiency than competitive techniques.

Abstract: Entropy coding/decoding techniques are disclosed in which data is coded alternately as a series of nonzero values and zero values until the transmitted data is consumed. Nonzero values may be coded first with transmission of data identifying a number of consecutive nonzero values that appear in scan order followed by transmission of the nonzero values themselves. Thereafter, if other data remains to be transmitted, data may be transmitted identifying a number of consecutive zero values that appear next in scan order followed by transmission of a next nonzero value encountered in scan order. By transmitting the nonzero values as a group, it is expected that the proposed entropy-coding process will achieve higher efficiency than competitive techniques.

Abstract: Some embodiments of the invention provide a media-editing application that performs frame rate conversion detection on a video. For a video that has been converted from one frame rate and format to another frame rate and format, the application detects the conversion method that has been used in the conversion of the video. Some embodiments perform this frame rate conversion detection by detecting patterns of repeating fields and/or frames in a video sequence created by the different conversion processes. Some embodiments compute (i) a frame difference value for each consecutive frames, (ii) a correlation score for the first and second fields of each frame, and (iii) a correlation score for the second field of each frame and the first field of a succeeding frame. Frame difference values are compared with each other to detect repeated frames and correlation scores are compared with each other to detect repeated fields.

Abstract: A method and system are provided for encoding a picture. The method includes encoding the picture into a first encoded picture using a first universal quantizer. If a size of the first encoded picture is greater than a maximum picture size, the method includes encoding the picture into a second encoded picture using a second universal quantizer. Before a second-pass encoding, the target size and maximum size for each slice is determined. During the second pass encoding, if a size of the encoded slice is greater than the maximum slice size, the method includes encoding the slice using a third local quantizer. If a size of the encoded slice is still greater than a maximum slice size, the method includes dropping coefficients from the encoded slice to ensure that the encoded size never exceeds the maximum size.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.

Abstract: A method and system are provided for encoding a picture. The method includes encoding the picture into a first encoded picture using a first universal quantizer. If a size of the first encoded picture is greater than a maximum picture size, the method includes encoding the picture into a second encoded picture using small quantizers for smooth regions of the picture and large quantizers for complex regions. If a size of the second encoded picture is still greater than a maximum picture size, the method includes encoding the picture into a third encoded picture with revised quantizers for complex regions and dropping high frequency coefficients if necessary to ensure the encoded picture size never exceeds the maximum size.

Abstract: Some embodiments of the invention provide a media-editing application that performs frame rate conversion detection on a video. For a video that has been converted from one frame rate and format to another frame rate and format, the application detects the conversion method that has been used in the conversion of the video. Some embodiments perform this frame rate conversion detection by detecting patterns of repeating fields and/or frames in a video sequence created by the different conversion processes. Some embodiments compute (i) a frame difference value for each consecutive frames, (ii) a correlation score for the first and second fields of each frame, and (iii) a correlation score for the second field of each frame and the first field of a succeeding frame. Frame difference values are compared with each other to detect repeated frames and correlation scores are compared with each other to detect repeated fields.

Abstract: Some embodiments of the invention provide a video preview generator that quickly generates preview displays of different parts of a video. The preview generator includes a skimming tool and a picture generator. The skimming tool is moveable across a representation of a video clip in order to identify different video pictures within the video clip. As the skimming tool moves across the video clip representation, the picture generator identifies and displays different video pictures for different positions of the skimming tool on the video clip. For at least some of the positions of the skimming tool, the picture generator presents a video picture that is not at the location identified by the skimming tool, but rather is at a nearby location and is easier to present in the preview than the video picture at the identified location.

Abstract: A method and system are provided for encoding a picture. The method includes encoding the picture into a first encoded picture using a first universal quantizer. If a size of the first encoded picture is greater than a maximum picture size, the method includes encoding the picture into a second encoded picture using small quantizers for smooth regions of the picture and large quantizers for complex regions. If a size of the second encoded picture is still greater than a maximum picture size, the method includes encoding the picture into a third encoded picture with revised quantizers for complex regions and dropping high frequency coefficients if necessary to ensure the encoded picture size never exceeds the maximum size.

Abstract: Some embodiments of the invention provide a media-editing application that performs frame rate conversion detection on a video. For a video that has been converted from one frame rate and format to another frame rate and format, the application detects the conversion method that has been used in the conversion of the video. Some embodiments perform this frame rate conversion detection by detecting patterns of repeating fields and/or frames in a video sequence created by the different conversion processes. Some embodiments compute (i) a frame difference value for each consecutive frames, (ii) a correlation score for the first and second fields of each frame, and (iii) a correlation score for the second field of each frame and the first field of a succeeding frame. Frame difference values are compared with each other to detect repeated frames and correlation scores are compared with each other to detect repeated fields.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.

Abstract: Some embodiments of the invention provide a video preview generator that quickly generates preview displays of different parts of a video. The preview generator includes a skimming tool and a picture generator. The skimming tool is moveable across a representation of a video clip in order to identify different video pictures within the video clip. As the skimming tool moves across the video clip representation, the picture generator identifies and displays different video pictures for different positions of the skimming tool on the video clip. For at least some of the positions of the skimming tool, the picture generator presents a video picture that is not at the location identified by the skimming tool, but rather is at a nearby location and is easier to present in the preview than the video picture at the identified location.

Abstract: Some embodiments of the invention provide a media-editing application that performs frame rate conversion detection on a video. For a video that has been converted from one frame rate and format to another frame rate and format, the application detects the conversion method that has been used in the conversion of the video. Some embodiments perform this frame rate conversion detection by detecting patterns of repeating fields and/or frames in a video sequence created by the different conversion processes. Some embodiments compute (i) a frame difference value for each consecutive frames, (ii) a correlation score for the first and second fields of each frame, and (iii) a correlation score for the second field of each frame and the first field of a succeeding frame. Frame difference values are compared with each other to detect repeated frames and correlation scores are compared with each other to detect repeated fields.

Abstract: A method and system are provided for encoding a plurality of integers with variable-length code tables constructed by combining a plurality of structured code tables. Each code table has an associated set of integer values; the sets are disjoint and exhaustive, so that every integer appears in exactly one set. An integer is encoded using the codebook associated with the set in which the integer appears.

Abstract: A method and system are provided for encoding a plurality of integers with variable-length code tables constructed by combining a plurality of structured code tables. Each code table has an associated set of integer values; the sets are disjoint and exhaustive, so that every integer appears in exactly one set. An integer is encoded using the codebook associated with the set in which the integer appears.

Abstract: A method and system are provided for encoding a plurality of integers with variable-length code tables constructed by combining a plurality of structured code tables. Each code table has an associated set of integer values; the sets are disjoint and exhaustive, so that every integer appears in exactly one set. An integer is encoded using the codebook associated with the set in which the integer appears.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.

Abstract: Methods and systems are provided for encoding and decoding a video stream. Each picture in a video stream can be divided into slices, each of which contains a contiguous row of macroblocks. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. By decomposing each picture into slices, the video stream can be efficiently converted for displays of varying size and/or quality. The encoded bitstream can include a slice table to allow direct access to each slice without reading the entire bitstream. Each slice can also be processed independently, allowing for parallelized encoding and/or decoding.