摘要:
Methods and apparatus teach a digital spectrum of a data file. The digital spectrum is used to map a file's position in multi-dimensional space. This position relative to another file's position reveals closest neighbors. Certain of the closest neighbors are grouped together, while others are differentiated. Grouping ceases upon application of a stopping function so that rightly sized, optimum numbers of file groups are obtained. Embodiments of stopping functions relate to curve types in a mapping of numbers of groups per sequential rounds of grouping, recognizing whether groups have overlapping file members or not, and/or determining whether groups meet predetermined numbers of members, to name a few. Properly grouped files can then be further acted upon.
摘要:
An image coding method and apparatus considering human visual characteristics are provided. The image coding method comprises (a) modeling image quality distribution of an input image in units of scenes such that the quality of an image input in units of scenes is gradually lowered from a region of interest to a background region, (b) determining a quantization parameter of each region constituting one scene according to the result of modeling of image quality distribution, (c) quantizing image data in accordance with the quantization parameter, and (d) coding entropy of the quantized image data.
摘要:
An image coding apparatus provides a run-length encoding unit RLE1 that subjects quantized coefficients which are obtained by quantizing frequency components of an image signal to a variable length coding process by using a run value Run that indicates the number of successive zero coefficients and a level value Lev that indicates a value of a non-zero coefficient following the zero coefficients. The run-length encoding unit RLE1 includes a reordering unit Lreodr for reordering level values Lev; a variable length coder LVLC for coding reordered level values ROLev by using a code table that is selected according to the value of a quantization parameter QP; a reordering unit Rreodr for reordering run values Run from high frequency component of the quantized coefficients to low frequency component; and a variable length coder RVLC for coding reordered run values RORun by using a code table that is selected according to the number of already-processed run values.
摘要:
Techniques and tools for encoding and decoding a block of frequency coefficients are presented. An encoder selects a scan order from multiple available scan orders and then applies the selected scan order to a two-dimensional matrix of transform coefficients, grouping non-zero values of the frequency coefficients together in a one-dimensional string. The encoder entropy encodes the one-dimensional string of coefficient values according to a multi-level nested set representation. In decoding, a decoder entropy decodes the one-dimensional string of coefficient values from the multi-level nested set representation. The decoder selects the scan order from among multiple available scan orders and then reorders the coefficients back into a two-dimensional matrix using the selected scan order.
摘要:
An apparatus and method for compressing binarized images (90) comprising receiving a binarized image (70) and generating a first sequence of first code symbols (80) representing the binarized image wherein at least one row of the image is represented in run-length encoded format and encoding a portion of the first sequence of code symbols using a preliminary encoding scheme, thereby to provide a first portion of a second sequence of code symbols, and, while encoding, accumulating the frequency of at least some of the first code symbols thus far encoded (100) and generating an additional portion of the second sequence using a modified version of the code scheme such that at least one subsequent code symbol in the first sequence with a large accumulated frequency is encoded more compactly in the second portion than at least one subsequent code symbol in the first sequence with a small accumulated frequency.
摘要:
Apparatus, systems and methods for using the selection of an appropriate parameter at decompression are disclosed. In particular, when adaptive block size discrete cosine transform compression is used to compress data, different combinations of sub-blocks can be generated. To decompress the different combinations of sub-blocks, the appropriate parameter is selected based on block size assignment information and the address of data in the data block.
摘要:
An apparatus and method for generating multiple descriptions of compressed data are comprised. Generally, a quantized bit stream is generated using a reference quantization step. The quantization bet stream is then re-quantized using a first quantization step to generate a first description of compressed data, wherein the first quantization step is determined based on a first required scaling of the reference quantization step. The quantized bit stream may also be re-quantized using a second quantization step to generate a second description of compressed data, wherein the second quantization step is determined on a second required scaling of the reference quantization step.
摘要:
A method and apparatus for variable accuracy inter-picture timing specification for digital video encoding is disclosed. Specifically, the present invention discloses a system that allows the relative timing of nearby video pictures to be encoded in a very efficient manner. In one embodiment, the display time difference between a current video picture and a nearby video picture is determined. The display time difference is then encoded into a digital representation of the video picture. In a preferred embodiment, the nearby video picture is the most recently transmitted stored picture. For coding efficiency, the display time difference may be encoded using a variable length coding system or arithmetic coding. In an alternate embodiment, the display time difference is encoded as a power of two to reduce the number of bits transmitted.
摘要:
Provided are a method, system, and program for decoding compressed data. Compressed data is received and decoded. An error is detected while decoding a first location in the compressed data. A reentry data set is accessed having a pointer to a second location in the compressed data following the first location and decoding information that enables decoding to start from the second location. The second location in the compressed data is accessed and the decoding information in the accessed reentry data set is used to continue decoding the compressed data from the second location.
摘要:
In an image-encoding scheme, an input image is decomposed into image blocks comprising multiple image elements. The image blocks are then encoded into encoded blocks. An encoded block comprises a first color codeword, a second color codeword, a color modifier codeword and a color index sequence. The color codewords are representations of a first and second base color located on a first line in color space. The modifier codeword is a representation of at least one color modifier for modifying the first base color along a second line to obtain multiple color representations along the line. The second line has a different direction as compared to the first line. The index sequence comprises color indices associated with a color representation selected form i) the representations on the second line and ii) at least one representation based on the second base color.