Improved and extended scalable image coding by spline approximation for a binary, gray-scale and color image

The image coding method for a gray-scale image, which can reconstruct the high quality image against several transformations such as scaling by expressing the image signal as the shape of the mathematical function, are proposed. This method is also applicable to a binary image, but it has not been applicable to a color image; there are some problems of quality with this method. The paper attempts to improve the quality and to extend the preview method to a color image. For the quality improvements, the processes involved in region segmentation and approximation for low frequency components are reformed. For the extension to a color image, the process of region segmentation is particularly reformed again. The performance of the proposed method is verified by some experiments. Although the quality problems remain to a certain extent, it is much better than previous results. The extension to a color image proves successful. Moreover, this improvement and extension can parallelize the process more effectively.