Method for quantization of histogram bin value of image

• US 20060233440A1
• Filed: 06/20/2006
• Published: 10/19/2006
• Est. Priority Date: 11/19/1999
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Ji Eun, Kim, Hyeon Jun
• Granted Patent: US 7,376,271 B2
• Time in Patent Office: Days
• US Class Current: 382/168
• CPC Class Codes: G06T 9/005 Statistical coding, e.g. Huffman, run length coding
• CPC Class Codes: G06V 10/56 relating to colour
• CPC Class Codes: H04N 1/644 using a reduced set of representative colours, e.g. each representing a particular range in a colour space

Abstract

A method for quantization of a color histogram bin value of an image or video, and more particularly, a method for non-uniform quantization of a color histogram bin value of an image (or video) according to the frequency of color occurrence is provided. The methods effectively represent the characteristics of a color histogram of an image in comparison to conventional art, and improve the performance of image retrieval when an image (video) retrieval search is conducted.

Claims

1. A method of quantizing bin values of a color histogram, the method comprising:

normalizing bin values by a maximum bin value;

separating the normalized bin values into a plurality of regions; and

uniformly quantizing each region, wherein the intervals of each region are quantized more finely closer to zero.

2. The method of claim 1, wherein a range of normalized bin values is from 0 to 1.

3. A method of describing a color image by non-uniform quantization of color histogram bin values for the image, comprising:

normalizing bin values by a maximum bin value, whereby the normalized bin values range from 0 to 1; and

non-uniformly quantizing each normalized bin value to an 8-bit value by dividing the range of normalized bin values into 6 regions, each region having a specific number of uniform quantization levels, wherein the specific number of uniform quantization levels in each of the 6 regions is 1, 25, 20, 35, 35 and 140, respectively.

4. A method of describing a color image by non-uniform quantization of color histogram bin values for the image, comprising:

normalizing bin values by a maximum bin value, whereby the normalized bin values range from 0 to 1; and

non-uniformly quantizing each normalized bin value to an 8-bit value by dividing the range of normalized bin values into 6 regions, wherein the threshold for each of the 6 regions is 0.000000001, 0.037, 0.08, 0.195, 0.32, respectively.

5. A method of generating a color histogram for an image, the color histogram containing a plurality of bins, the method comprising:

accumulating bin values;

normalizing bin values by a maximum bin value, whereby the normalized bin values range from 0 to 1; and

non-uniformly quantizing each normalized bin value to an 8-bit value by dividing the range of normalized bin values into 6 regions, and allocating a different number of quantization levels to each region.