Fast Image Compression Algorithms Based on Fractal Coding Technique

[[abstract]]在現今日益蓬勃的電子資訊世界裡，影像已經是未來資料傳輸的重要趨勢；然而，傳輸的速度取決於頻寬和容量的限制，更小的檔案大小將協助使用者更迅速地完成需求，因此資料或影像的壓縮便成了重要的研究。為了舒緩網路傳輸的壓力，我們應該使用適當的影像壓縮格式來處理我們的影像。而正確的影像壓縮法可以有效的減少影像的資料量大小、加速網路的傳輸、進而節省我們的金錢。 由於碎形影像壓縮在編碼上需要耗費大量時間來找尋最契合的定義域區塊及最佳的轉換函數，對於使用者來說，如果影像要在網路上傳送，或者是儲存在硬碟裡，都不想耗費太多時間在壓縮影像上。在本碩士論文中，我們主要目的在於減少碎形壓縮的編碼時間，因此提出了許多的演算法來加以改進，希望能夠在影響影像品質最小的情況下，找出一種演算法能有效地減少碎形壓縮的編碼時間。[[abstract]]Nowadays, internet and information technology are widely spread in our life. Image transmission is an important trend in the future. And one of the important problems in such applications is the limit of transmission bandwidth and storage capacity. The smaller file size will help us to meet requirement. Thus, technique of the compression has become an important research topic. In order to speed up the internet transmission, it is useful for us to develop algorithm. Besides, an efficient image compression can reduce the size of image efficiently and decrease transmission time. In the fractal image compression, most of the time is spent on finding the best matching domain block and determine the transform function. If we want to transmit an image in the internet or store it, we would not like to spend much time on compressing it. Thus, we propose several algorithms to speed up fractal image coding under the condition that keep the image quality in this thesis