Image compression method

• US 7,031,514 B1
• Filed: 07/05/2000
• Issued: 04/18/2006
• Est. Priority Date: 08/27/1999
• Status: Expired due to Fees

• Current Assignee: Celartem Technology Inc.
• Original Assignee: Celartem Technology Inc.
• Inventors: Shindo, Jiro
• Primary Examiner(s): Johns, Andrew W.
• Assistant Examiner(s): Alavi, Amir
• Application Number:
  US10/069,227
• Time in Patent Office: 2,113 Days
• Field of Search: 382/162, 382/164, 382/165, 382/173, 382/232, 382/233, 382/240, 382/246, 382/247, 382/251, 382/253, 382/278, 382/284, 375/240.03, 375/240.12, 375/240.16, 375/240.22, 375/240.24, 375/240.25, 348/391.1, 348/631, 358/515, 358/520
• US Class Current: 382/164
• CPC Class Codes: G06T 9/005 Statistical coding, e.g. Huffman, run length coding
• CPC Class Codes: H04N 1/64 Systems for the transmission or the storage of the colour picture signal; Details therefor, e.g. coding or decoding means therefor H04N19/00 takes precedence

Abstract

Bitmap digital image data having one or more color channels is divided into image sizes corresponding to an optimum processing unit set according to computer'"'"'s processing capability and requested image quality. Each unit image data is further divided according to the respective color channels in order to generate multiple minimum processing units of image data. After respective horizontal rows of the minimum processing unit of image data are 2D-vectored based on the horizontal positions x and luminance levels y of the respective pixels therein, quantized according to changes in luminance levels using line elements connecting the starting points and end points of the respective rows as reference vectors, and applied with shaping processing, the respective vertical rows are 2D-vectored based on the horizontal positions x and luminance levels y in the same manner and quantized according to the changes in luminance levels using line elements connecting the starting point and the end point of the respective rows as reference vectors in order to convert the image data into compressed image data with a matrix structure based on the significance of the luminance information contained in the respective pixels. After said minimum units of compressed image data are further compressed mathematically, the color channels are integrated in order to generate optimum processing units of compressed image data; and they are further integrated in order to generate compressed image data for the entire original image.

Claims

1. An image compression method comprising:

producing a 2D-vectored data pattern according to the positions and luminance levels of respective pixels in respective horizontal rows of digital image data;

quantizing the data according to the change in the luminance levels with reference to the line elements connecting the starting points and the end points of said respective rows;

data from respective vertical rows of said horizontally vectored and quantized image data;

producing 2D-vectored according to the positions and luminance levels of the respective pixels according to the degrees of change in the luminance levels with reference to the line elements connecting the starting points and the end points of the respective vertical rows,

converting the image data into compressed image data in matrix form based on the significance levels of the luminance information of the respective pixels.

2. The image compression method of claim 1, further comprising:

dividing said bitmap digital image data into unit image data of a prescribed size;

applying horizontal vectoring and quantization and subsequent vertical vectoring and quantization to the divided unit image data in order to convert them into unit compressed image data in matrix form; and

integrated the unit compressed image data.

3. The image compression method according to claim 1, further comprising:

dividing the digital image data into respective color channels;

converting the divided image data for the respective color channels into respective compressed image data in matrix form; and

integrating said compressed image data in matrix form into one compressed image.

4. The image compression method of claim 1, further including:

applying a mathematical compression to said compressed image data in matrix form.

5. The image compression method of claim 1, further including:

using line elements connecting the starting points and the end points of the respective vertical row or the respective horizontal rows as reference vectors for calculating positive and/or negative maximum deviation points in said units, using line elements connecting each two neighboring points at said starting points, the end points, and said maximum deviation points as new reference vectors for calculating new positive and/or negative maximum deviation points in said units in order to calculate said maximum deviation points;

repeating the using steps until the deviations of said respective maximum points with respect to the reference vectors lose their significance as desired image data, and respective pixels are divided according to the degree of deviation at said respective maximum deviation points in order to generate multiple hierarchical data containing different numbers of bits.

6. The image compression method of claim 5 wherein when said digital image data is 8-bit data, said multiple hierarchical data are constructed as four groups organized as first through fourth hierarchical data comprising 8 bits, 6 bits, 4 bits, and 1 bit, respectively.