Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

90 results about "Lossless compression algorithm" patented technology

A lossless compression algorithm compresses data such that it can be decompressed to achieve exactly what was given before compression. The opposite would be a lossy compression algorithm. Lossy compression can remove data from a file.

Lossless compression algorithm for hyperspectral data

Lossless compression techniques provide efficient compression of hyperspectral satellite data. The present invention combines the advantages of a clustering with linear modeling. A number of visualizations are presented, which help clarify why the approach of the present invention is particularly effective on this dataset. At each stage, the algorithm achieves an efficient grouping of the data points around a relatively small number of lines in a very large dimensional data space. The parametrization of these lines is very efficient, which leads to efficient descriptions of data points. The method of the present invention yields compression ratios that compare favorably with what is currently achievable by other approaches.
Owner:SEC OF COMMERCE UNITED STATES OF AMERICA

Method of encoding/decoding color QR code

This invitation discloses a method of encoding / decoding a color QR (Quick Response) code. The method maintains the reliability and robustness of a standard black and white QR code, and employs a lossless compression algorithm to make the data capacity of a color QR code much larger than the data capacity of other colored two-dimensional code of a same kind. In addition, encoding colors are not required to be the most distant from each other in an RGB color space in order to enhance color resolution. A process of encoding / decoding a color QR code does not require color space transfer, i.e., color information loss can be avoided. Color QR cod decoding has no special requirements for ambient lighting, and does not need to utilize reference colors as a palette, thereby greatly reducing computational complexity, and obtaining 100% decoding accuracy.
Owner:GUILIN UNIV OF ELECTRONIC TECH

Method of high quality digital image compression

This image compression applies a lossless compression algorithm and a lossy compression algorithm to code the differential value of the adjacent pixels. If lossy algorithm is selected, it codes the differential value of the present pixel and the reconstructed previous pixel. In quantizing the differential value of adjacent pixel components, a variable range of interval of value is predetermined with smaller interval range in values closer to “0” and larger interval range farer from “0”. The region with less mean variance, less quantization error will be allowed and the region with larger mean variance, more quantization error is allowed
Owner:TAIWAN IMAGINGTEK

First-order difference prefix notation coding method for lossless compression of image data

The invention discloses a first-order difference prefix notation coding method for the lossless compression of image data, which comprises the following steps of: 1, pre-processing original image data to obtain first-order differences between adjacent pixel values; 2, counting the probabilities of occurrence of each first-order difference, and re-sequencing the first-order differences from higher probabilities to lower probabilities to obtain new first-order differences; 3, performing first-order difference prefix notation coding processing on the new first-order differences obtained by the step 2 to obtain a prefix code table and a suffix code table; 4, performing order-reduction processing on suffix codes in the step 3 by adopting a suffix derivation method; and 5, performing coding processing on primary prefix codes in the step 4 according to bit planes by adopting dichotomy. The method ensures relatively lower computational complexity, simple coding, high coding and decoding efficiency remarkably higher than that of JPEG2000, and no need of adopting special compression and decompression chips, and compared with a conventional lossless compression algorithm, remarkably increases a compression ratio to be equivalent to that of the international standard JPEG2000.
Owner:SHANGHAI UNIV

Audio bitstream data structure arrangement of a lossy encoded signal together with lossless encoded extension data for said signal

Lossless compression algorithms can only exploit redundancies of the original audio signal to reduce the data rate, but not irrelevancies as identified by psycho-acoustics. Lossless audio coding schemes apply a filter or transform for decorrelation and then encode the transformed signal. The encoded bit stream comprises the parameters of the transform or filter, and the lossless representation of the transformed signal. However, in case of lossy based lossless coding the additional amount of information exceeds the amount of data for the base layer by a multiple of the base layer data amount. Therefore the additional data cannot be packed completely into the base layer data stream e.g. as ancillary data. The at least two data streams resulting from the combination of lossy coding format with a lossless coding extension are the base layer containing the lossy coding information and the enhancement data stream for rebuilding the mathematically lossless original input signal. Furthermore several intermediate quality layers are possible. However, these data streams are not independent from each other. Every higher layer depends on the lower layers and can only be reasonably decoded in combination with these lower layers. According to the invention, a special combination of one-time header information with repeated header information in a block structure is used, which kind of combination depends on the type of application. Assignment information data identify the different parts or layers of the lossless format belonging to one input signal. Synchronisation data are used to combine the different data streams or parts or layers to a single lossless or intermediate output signal. These features are used in a file format and in a streaming format.
Owner:THOMSON LICENSING SA

Improved train control system security data interaction method

The invention discloses an improved train control system secure data interaction method, which comprises the following steps of: expanding the shared key of a data transceiver and the length of a random number generated and shared by the transceiver, and calculating a session key with an increased key length by matching with a corresponding SM4 algorithm; dividing the security data X of the train control system into blocks according to N bits, using a data block and a full text of a session key as input in each round, performing iterative computation by using a corresponding SM4 algorithm, and generating an N-bit operation result Hi corresponding to the corresponding data block; regarding the operation result Hi as encrypted data of the corresponding data block, and covering the corresponding data block, so that the security encryption of the security data X of the train control system is realized; and selecting a corresponding lossless compression algorithm according to the type of the train control system security data, performing data lossless compression on the full-text encrypted train control system security data X, and sending the compressed data X to a receiver. According to the method, the data security is greatly improved, and meanwhile, the occupancy rate of wireless resources is reduced.
Owner:CHINA RAILWAYS CORPORATION +2
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products