Study on a Basic Concept of Highly Efficient Coding Model for Super High Definition Images

随着硬件性能的提高和多媒体内容的增加，高分辨率、高像素精度的图像得到了广泛的应用。在普通尺寸的显示器上，很难以原始分辨率完整地表示大尺寸图像，例如超高清（SHD）图像。在这种情况下，首先显示一个缩小的图像，让用户选择一个他希望看到细节的感兴趣的区域。然后从码流中提取所选区域的图像数据。因此，非常希望引入一些部分可解码的代码，其中码流的任何部分都可以独立解码。为了实现这种可扩展性，我们将图像分割或分解为大小合适的块或块，并通过DPCM方法或正交变换分别对每个块进行编码。然而，如果在熵编码中使用变长码，则很难检测到码序列中每个块的起始位置。在这项研究中，我们提出了一种新的低损耗编码方法，可以在不从编码序列的起点解码的情况下显示图像的感兴趣区域。我们还提出了部分可解码的变长码，命名为修改的Golomb-Rice码。

Images of high resolution and pixel accuracy are coming into wide use with the improvement of hardware performance and the increase in multimedia contents. It is difficult to represent a large size image entirely, such as a super high definition (SHD) image, on an ordinary size monitor with the original resolution. In this case, a reduced image is displayed at first to let user select a region of interest where he hopes to see the detail. Then image data of the selected area are extracted from code stream. Hence, it is highly desired to introduce some partially decodable codes with which any parts of the code stream can be decoded independently. In order to realize such scalability, we divide or decompose an image into blocks or tiles of proper size, and encode each block respectively by DPCM method or orthogonal transform. However, it is difficult to detect the start position of each block in code sequence if variable length code is used in entropy coding. In this study, we propose a new loss less coding method enable to display the region of interest of the image without decoding from the start point of the code sequence. We also propose apartially decodable variable length code named modified Golomb-Rice code.