摘要:
A compression and decompression system in which a reversible wavelet filter are used to generates coefficients from input data, such as image data. The reversible wavelet filter is an efficient transform implemented with integer arithmetic that has exact reconstruction. The present invention uses the reversible wavelet filter in a lossless system (or lossy system) in which an embedded codestream is generated from the coefficients produced by the filter. An entropy coder performs entropy coding on the embedded codestream to produce the compressed data stream.
摘要:
Compound document images are usually high resolution and high quality images that include color, graphics, and images in addition to text. The need for good compression is important for storage and transmission. Due to the large size, even compressed, it is often difficult to access document images quickly and efficiently for display on monitors. The nascent JPM file format enables the best compound document image compression in terms of rate-distortion. However, the access into a JPM file is limited by the access features of the coders used. JPEG 2000 is an image coding system that allows access to lower resolutions, progressive bit-rates, and regions of interest.
摘要:
A compression and decompression system in which a reversible wavelet filter are used to generates coefficients from input data, such as image data. The reversible wavelet filter is an efficient transform implemented with integer arithmetic that has exact reconstruction. The present invention uses the reversible wavelet filter in a lossless system (or lossy system) in which an embedded codestream is generated from the coefficients produced by the filter. An entropy coder performs entropy coding on the embedded codestream to produce the compressed data stream.
摘要:
A method and apparatus for performing scalar quantization with a power of two step size is described. In one embodiment, the method comprises receiving a sequence of image data to compress and specifying scalar quantization with a power of two step size using three bit values to apply to the sequence of image data.
摘要:
A compression and decompression system in which a reversible wavelet filter are used to generates coefficients from input data, such as image data. The reversible wavelet filter is an efficient transform implemented with integer arithmetic that has exact reconstruction. The present invention uses the reversible wavelet filter in a lossless system (or lossy system) in which an embedded codestream is generated from the coefficients produced by the filter. An entropy coder performs entropy coding on the embedded codestream to produce the compressed data stream.
摘要:
A compression and decompression system in which a reversible wavelet filter are used to generates coefficients from input data, such as image data. The reversible wavelet filter is an efficient transform implemented with integer arithmetic that has exact reconstruction. The present invention uses the reversible wavelet filter in a lossless system (or lossy system) in which an embedded codestream is generated from the coefficients produced by the filter. An entropy coder performs entropy coding on the embedded codestream to produce the compressed data stream.
摘要:
A method and apparatus for encoding and decoding data that includes generating transformed signals in response to input data. In one embodiment, the transformed signals are generated using a reversible wavelet transform. The present invention also includes a method and apparatus for compressing the transform signals into data representing a losslessly compressed version of the input data. In one embodiment, the present invention decomposes the input data using reversible wavelet transforms.
摘要:
A method and apparatus for editing an image while maintaining codestream size is described. In one embodiment, the method comprises determining a portion of a codestream to edit, decoding the portion of the codestream, performing an edit to the decoded portion of the codestream, recompressing edited data into coded data, and generating a replacement portion for the portion of the codestream by making size of the replacement portion equal to size of the portion of the codestream by adding padding to the replacement tile if the replacement tile is smaller than the portion of the codesteam or quantizing the replacement tile if the replacement tile is larger than the portion of the codestream.
摘要:
A method and apparatus for selecting layers for quantization based on sideband information is described. In one embodiment, the method comprises receiving a codestream of compressed image data organized in multiple layers. Each of the layers comprises coded data that adds visual value to the image. The method also includes selecting one or more of the layers for quantization based on sideband information accompanying the codestream and decompressing non-quantized layers of the codestream.
摘要:
A method and apparatus for outputting a codestream as multiple tile-part outputs with packets from tiles being output in each tile-part is described. In one embodiment, the method comprises coding of each tile of an input codestream, outputting packets of each tile as part of an output codestream as a first complete tile-part, storing remaining layers of each tile in a buffer, and outputting additional packets of each tile from the remaining layers as a second complete tile-part.