A Research on Fractal Image Coding for Mobile Image Communications

移动图像通信中的分形图像编码研究

基本信息

批准号：
13450154
负责人：
TANIMOTO Masayuki
金额：
$ 3.97万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450154/
关键词：
Fractal Correlation Collage theorem Error resilience Picture coding Mobile communication

项目摘要

Through this research, the following results were obtained :1. In fractal image decoding process, we investigated theoretically the mechanism of the propagation of image degradation caused by errors of received compressed data. We found that the propagated errors are about 2.4 times as the errors of compressed data regardless of the search area in encoding process.2. We proposed a new coding method for error resilience by sending the image twice with the same amount of data as the single image. This is realized by using double-sized range blocks and a new criterion to determine the domain block.3. In the proposed method, we determined the optimal shape of enlarged range blocks from the mean square error between range blocks and domain blocks. We confirmed the results from the viewpoint of the coding efficiency.4. We also investigated the mechanism of the error detection in the decoding process. We found that the error detection using threshold sometimes fails, and this hampers error recovering and causes image degradation.5. To prevent misdetection of error as 4, we introduced a pre-processing in the encoder, which selects only domain blocks that causes no error misdetection.6. Using encoder and decoder based on 5, we succeeded to suppress the misdetection of errors.We confirmed that the proposed method outperforms the conventional method with 2-3 dB gain of PSNR in an erroneous channel environment.

通过这项研究，获得了以下结果：1。在分形图像解码过程中，我们从理论上研究了由收到的压缩数据错误引起的图像降解的传播机制。我们发现，无论编码过程中的搜索区域如何，繁殖错误是压缩数据的错误约为2.4倍。2。我们通过将图像与单个图像相同的数据发送两次，提出了一种新的编码方法，以进行错误弹性。这是通过使用双尺寸范围块和一个新标准来确定域块3来实现的3。在提出的方法中，我们确定了从范围块和域块之间的均方误差的放大范围块的最佳形状。我们从编码效率的角度证实了结果。4。我们还研究了解码过程中误差检测的机制。我们发现使用阈值的错误检测有时会失败，这会阻碍错误恢复并导致图像降解5。为了防止误差为4，我们在编码器中引入了预处理，该域仅选择不会导致错误误导的域块。6。使用基于5的编码器和解码器，我们成功地抑制了错误的错误检测。我们确认，在错误的通道环境中，所提出的方法以PSNR的2-3 dB增益优于常规方法。