# GRAY-LEVEL IMAGE CONTOURS EXTRACTION & COMPRESSION USING WAVELET TRANSFORM

### Ali Ukasha

#### Abstract

This paper presents a method of contour extraction and compression from grey level image. Single step parallel contour extraction (SSPCE) method is used for the binary image after inverse wavelet transform is applied to the details images. Then the contours are compressed using either Ramer or Trapezoid methods in spatial domain. The proposed algorithms are applied in spectral domain using single-level wavelet transform (WT). Effectiveness of the contour extraction and compression for different classes of images is evaluated. In the paper the main idea of the proposed procedure for both contour extraction and image compression are performed. To compare the results, the mean square error, signal-to-noise ratio criterions, and compression ratio (bit per pixel) were used. The simplicity to obtain compressed image and extracted contours with accepted level of the reconstruction is the main advantage of the proposed algorithms.

#### References

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#### Paper Citation

#### in Harvard Style

Ukasha A. (2012). **GRAY-LEVEL IMAGE CONTOURS EXTRACTION & COMPRESSION USING WAVELET TRANSFORM** . In *Proceedings of the First International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,* ISBN 978-989-8565-28-0, pages 99-104. DOI: 10.5220/0005414600990104

#### in Bibtex Style

@conference{ictrs12,

author={Ali Ukasha},

title={GRAY-LEVEL IMAGE CONTOURS EXTRACTION & COMPRESSION USING WAVELET TRANSFORM},

booktitle={Proceedings of the First International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,},

year={2012},

pages={99-104},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005414600990104},

isbn={978-989-8565-28-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the First International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,

TI - GRAY-LEVEL IMAGE CONTOURS EXTRACTION & COMPRESSION USING WAVELET TRANSFORM

SN - 978-989-8565-28-0

AU - Ukasha A.

PY - 2012

SP - 99

EP - 104

DO - 10.5220/0005414600990104