Title :
Enhancement of lossy compressed images by modeling with Bernstein polynomials
Author_Institution :
Dept. of Electr. Eng., Univ. Fed. de Santa Catarina, Florianopolis, Brazil
Abstract :
A non-iterative post-processing enhancement technique is proposed for images degraded by either the JPEG-DCT or the JPEG-LS (LOCO) lossy coding algorithm. A degraded image is classified into active and smooth regions. A distance transform is applied to the resulting classification, and is used to determine the size and order of a Bezier surface patch. These Bezier blending surfaces, built with Bernstein polynomials, provide an interesting representation for the image. This approach mitigates the quantization noise while preserving strong edges and textures. Results illustrate the significant visual improvement achieved with a computational complexity of O(n).
Keywords :
data compression; discrete cosine transforms; image classification; image coding; image enhancement; image representation; image segmentation; polynomials; transform coding; Bernstein polynomials; Bezier blending surfaces; Bezier surface patch; JPEG-DCT lossy coding algorithm; JPEG-LS lossy coding algorithm; active regions; classification; computational complexity; degraded image; distance transform; edges; noniterative post-processing enhancement technique; quantization noise; representation; smooth regions; textures; visual improvement; Degradation; Discrete cosine transforms; Image coding; Image edge detection; Image restoration; Iterative algorithms; Polynomials; Quantization; Signal processing algorithms; Surface morphology;
Conference_Titel :
Image Processing. 2002. Proceedings. 2002 International Conference on
Print_ISBN :
0-7803-7622-6
DOI :
10.1109/ICIP.2002.1038152