• Title/Summary/Keyword: 호모모픽 필터링

Search Result 3, Processing Time 0.015 seconds

A Study on Localization of Text in Natural Scene Images (자연 영상에서의 정확한 문자 검출에 관한 연구)

  • Choi, Mi-Young;Kim, Gye-Young;Choi, Hyung-Il
    • Journal of the Korea Society of Computer and Information
    • /
    • v.13 no.5
    • /
    • pp.77-84
    • /
    • 2008
  • This paper proposes a new approach to eliminate the reflectance component for the localization of text in natural scene images. Natural scene images normally have an illumination component as well as a reflectance component. It is well known that a reflectance component usually obstructs the task of detecting and recognizing objects like texts in the scene, since it blurs out an overall image. We have developed an approach that efficiently removes reflectance components while Preserving illumination components. We decided whether an input image hits Normal or Polarized for determining the light environment, using the histogram which consisted of a red component. In the normal image, we acquired the text region without additional processing. Otherwise we removed light reflecting from the object using homomorphic filtering in the polarized image. And then this decided the each text region based on the color merging technique and the Saliency Map. Finally, we localized text region on these two candidate regions.

  • PDF

Study on OCR Enhancement of Homomorphic Filtering with Adaptive Gamma Value

  • Heeyeon Jo;Jeongwoo Lee;Hongrae Lee
    • Journal of the Korea Society of Computer and Information
    • /
    • v.29 no.2
    • /
    • pp.101-108
    • /
    • 2024
  • AI-OCR (Artificial Intelligence Optical Character Recognition) combines OCR technology with Artificial Intelligence to overcome limitations that required human intervention. To enhance the performance of AI-OCR, training on diverse data sets is essential. However, the recognition rate declines when image colors have similar brightness levels. To solve this issue, this study employs Homomorphic filtering as a preprocessing step to clearly differentiate color levels, thereby increasing text recognition rates. While Homomorphic filtering is ideal for text extraction because of its ability to adjust the high and low frequency components of an image separately using a gamma value, it has the downside of requiring manual adjustments to the gamma value. This research proposes a range for gamma threshold values based on tests involving image contrast, brightness, and entropy. Experimental results using the proposed range of gamma values in Homomorphic filtering suggest a high likelihood for effective AI-OCR performance.

Improved Text Recognition using Analysis of Illumination Component in Color Images (컬러 영상의 조명성분 분석을 통한 문자인식 성능 향상)

  • Choi, Mi-Young;Kim, Gye-Young;Choi, Hyung-Il
    • Journal of the Korea Society of Computer and Information
    • /
    • v.12 no.3
    • /
    • pp.131-136
    • /
    • 2007
  • This paper proposes a new approach to eliminate the reflectance component for the detection of text in color images. Color images, printed by color printing technology, normally have an illumination component as well as a reflectance component. It is well known that a reflectance component usually obstructs the task of detecting and recognizing objects like texts in the scene, since it blurs out an overall image. We have developed an approach that efficiently removes reflectance components while preserving illumination components. We decided whether an input image hits Normal or Polarized for determining the light environment, using the histogram which consisted of a red component. We were able to go ahead through the ability to extract by reducing the blur phenomenon of text by light because reflection component by an illumination change and removed it and extracted text. The experimental results have shown a superior performance even when an image has a complex background. Text detection and recognition performance is influenced by changing the illumination condition. Our method is robust to the images with different illumination conditions.

  • PDF