Progressive image transmission (PIT) transmits the most significant portion of a picture, followed by its less important portions. The mechanism can be used in Web-based applications while users are browsing images. However, most PIT methods use the same pixel interpolation scheme for the entire picture, without considering the differences among image blocks. This paper analyzes the efficiency of pixel interpolation schemes and test several decomposition mechanisms. The contribution results in an adaptive image transmission scheme, which takes the differences of picture portions into consideration. Moreover, this study tested 200 pictures in different categories and parameters. In consequence, the overall bit rates can be reduced significantly with good PSNR values and user satisfaction. The visual result is superior to progressive JPEG on both objective (quantitative) and subjective (human) measures. An error recovery procedure is also implemented in case that the transmitted pictures need to be fully recovered.
