30 results about "Color image coding" patented technology

A lossless image encoding / decoding method and apparatus. The lossless color image encoding apparatus includes a motion prediction image generator estimating a motion between a previous image and a current image and outputting a corresponding prediction image, a residue generator generating a temporal residue corresponding to a difference between a prediction image generated by the motion prediction image generator and the corresponding block of the current image with respect to different components of the color image, a prediction residue generator generating prediction residues by defining a linear-transformed value of one residue among the different components of the color image output from the residue generator as a predictor and using differences between each of the residues of the other components and the predictor, and an entropy encoder receiving the residue forming the predictor from the residue generator and the prediction residues from the prediction residue generator and generating a bitstream. Encoding methods, decoding apparatuses, and decoding methods can be implemented similarly.

A color image residue transform and / or inverse transform method and apparatus, and a color image encoding and / or decoding method and apparatus using the same are provided. The residue transform method includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and transforming the residue by using a relation between residues of color image components. The residue inverse transform method includes: generating a residue for each component by performing residue inverse transform of the residue transformed original image; and restoring the original image by adding a predicted image to the residue of each component. Also, the color image lossless encoding method using the residue transform includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and performing encoding by transforming the residue by using the relation between residues of predetermined components. The decoding method includes: extracting residue transformed image data from the coded data of the original image; generating a residue for each component by performing residue inverse transform of the residue transformed image data; and restoring the original image by adding a predicted image to the residue of each component. According to the methods and apparatuses, by performing transform between residues of each color component, the redundancy of the residue of each color component is removed such that when a color image is encoded, a higher compression efficiency can be achieved.

The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF / PNG decoder.

A color image encoding and / or decoding system, medium, and method using inter-color-component prediction in a frequency domain. To encode an original image, including at least two or more image components, frequency domain transform may be performed with of each component of a color image, color component transform of the frequency domain transform coefficients, in frequency domain, may be performed based on the relationship between transform coefficients of the color image components in order to remove redundant information between color components, performing, and entropy encoding the removed redundant information data. According to the method, medium, and system, a color image or video data can be directly compressed effectively without a conventional color transform process. Furthermore, by using the relationship between image components, redundant information between color components varying with respect to the encoding mode may be removed so that the encoding efficiency can be enhanced.

The image coding method is used to code images to generate a coded stream. The image coding method includes: writing, into a sequence parameter set in the coded stream to be generated, a first parameter representing a first bit-depth that is a bit-depth of a reconstructed sample in the images; and writing, into the sequence parameter set, a second parameter which is different from the first parameter and represents a second bit-depth that is a bit-depth of an Intra Pulse Code Modulation (IPCM) sample in the images.

A method and system for encoding a color image into a monochrome halftoned image for printing, includes the use of a decoding mechanism to recover color information from the monochrome halftone image. A luminance channel associated with the color image can be utilized as the grayscale input to a half-toning process, while chrominance channels are utilized to determine displacements of the halftone dots. The color information can then be restored utilizing a template to measure the displacements of the halftone dots and hence the color information. Thus, the color information can be preserved without visual impact.

Optimized color codecs and methods of compressing and decompressing color images using programmable color space parameters are provided. In accordance with one method of encoding a color image, input data comprising input image pixel data and color space parameters is provided. The input image pixel data is compressed based on the color space parameter data. The color space parameter data is then appended to the compressed image pixel data. In accordance with one method of decoding a compressed color image, compressed data is provided that comprises compressed image pixel data and color space parameters. The color space parameters are separated from the compressed image pixel data. The compressed image pixel data is then decompressed based on the color space parameters.

A dense map creation method based on g2o and random fern algorithm belongs to the field of robot real-time positioning and map creation. First, a camera pose model and a weighted TSDF model fused with 3D point truncated information are constructed to accurately represent the surface on which the object is created. Secondly, an improved loop closure detection method is proposed and combined with a random fern color image encoding strategy to optimize the TSDF model. Finally, use the g2o graph optimization library to solve the constraint function and establish the optimal edge between the data sets. Experimental results show that the hybrid optimized pose model can quickly establish a global SLAM map and effectively identify areas that have been reached.

The application relates to an image acquisition device and a camera method, which belong to the monitoring field. The image acquisition device includes: an image sensor, a light fill device and a filter assembly, and the image sensor is located on the light output side of the filter assembly; it also includes an image signal processing unit, a code compression unit and an analysis unit; the image sensor is used to pass multiple exposures Generate and output the first image signal and the second image signal; the supplementary light device includes a first supplementary light device, and the first supplementary light device is used to perform near-infrared supplementary light in a stroboscopic manner; the filter assembly includes a first filter, The first optical filter allows visible light and part of near-infrared light to pass through; the image signal processing unit is used to obtain a grayscale image according to the first original image signal, and obtain a color image according to the second original image signal; the encoding and compression unit is used to perform color image processing Compression coding; the analysis unit is used for intelligent analysis of grayscale images. The present application can improve the precision of analysis results.

The invention discloses an image encryption method and device based on cascade transformation, and the method comprises the steps: S1, generating a phase mask according to a chaotic sequence; s2, randomly generating a real integer matrix, and encoding the real integer matrix and the first color image to generate a full quaternion matrix; s3, performing modulation and quaternion Gyrator transformation on the full quaternion matrix according to the phase mask to obtain a first amplitude and a first phase; s4, encoding the first amplitude and the second color image to generate a quaternion matrix, and performing amplitude truncation to obtain a second amplitude and a second phase; s5, multiplying the first phase by the second phase, and performing modulation and quaternion Gyrator transformation on the quaternion matrix according to a phase mask to obtain a third amplitude and a third phase; s6, repeatedly executing S4 and S5 until the Nth amplitude and the Nth phase of the last color image are obtained. The method has relatively high transmission efficiency and security.

The invention discloses a color image encryption method and device, wherein the method includes: encoding the color image into a first quaternion matrix; dividing the quaternion matrix into sub-blocks that do not Perform modulation and quaternion Gyrator transformation to obtain the second quaternion matrix; extract the real component and the first to third imaginary components of the second quaternion matrix, and construct the first complex matrix and the second complex matrix ; Perform multi-resolution decomposition on the first complex matrix and the second complex matrix to obtain the approximate component and the detail component, and recombine to obtain the third complex matrix and the fourth complex matrix; perform angle calculation on the third complex matrix and the fourth complex matrix is the Gyrator transformation of β to obtain the first ciphertext image and the second ciphertext image respectively. The method effectively avoids the cumbersome single-channel processing method, can hide the meaningful content of the image, and can be applied to the field of multimedia information security.

A color image residue transform and / or inverse transform method and apparatus, and a color image encoding and / or decoding method and apparatus using the same are provided. The residue transform method includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and transforming the residue by using a relation between residues of color image components. The residue inverse transform method includes: generating a residue for each component by performing residue inverse transform of the residue transformed original image; and restoring the original image by adding a predicted image to the residue of each component. Also, the color image lossless encoding method using the residue transform includes: obtaining a residue corresponding to the difference of an original image and a predicted image; and performing encoding by transforming the residue by using the relation between residues of predetermined components. The decoding method includes: extracting residue transformed image data from the coded data of the original image; generating a residue for each component by performing residue inverse transform of the residue transformed image data; and restoring the original image by adding a predicted image to the residue of each component. According to the methods and apparatuses, by performing transform between residues of each color component, the redundancy of the residue of each color component is removed such that when a color image is encoded, a higher compression efficiency can be achieved.

The invention relates to a 3D data based aircraft surface manufacture quality detection method. The method comprises that a series of sine stripes are projected to a surface sheath of an aircraft; left and right cameras collect stripe images modulated by the surface; the phases of the stripe images are expanded; the left and right images are matched according to phase and epipolar geometrical constraint; a 3D point cloud model of the surface of the aircraft is reconstructed; a rivet region of interest is extracted, and according to the correspondence between an image area and the 3D model, rivets are positioned in the point cloud model; a curved surface fitting method is used to obtain a reference configuration of the surface of the aircraft; the distance between a point of the rivet to the reference configuration is calculated, and a region of interest of concave-convex rivets is obtained; and a pseudo color image is coded and projected to the surface of the aircraft, and a visual result is formed. Thus, depth information of the rivet region of interest can be detected, the robustness and precision are high, a quantified and visual detection result can be provided, and a new approach suitable for the rivet region of interest of the aircraft surface is provided.

The invention provides a novel color image coding method. The method is characterized by, according to the characteristic that a transfer matrix between RGB and YCbCr color space is a non-unitary matrix, that is, unequivalence of error between RGB images and YCbCr images, with minimization of interpolation error of an RGB space being an objective, carrying out combined optimized filtering on three components of Y, Cb and Cr, after filtering, the resolution of the component Y keeping unchanged, and the resolutions of the two components Cb and Cr being reduced; after finishing filtering, carrying out compression on the three components through a standard JPEG image compression method; and carrying out coding on the RGB images based on the above, so that coding efficiency is improved greatly. The method can improve coding efficiency of the RGB color images, is not high in complexity and is easy to realize.