图像压缩

Experimental results show that the algorithm can segmentalize ROI effectively, CR is higher than 30, PSNR of the whole image is higher than 42 dB, and the object keeps original fidelity. Inter-frame CR is about 7, background has cumulative error and PSNR is higher than 40 dB.

实验结果表明，该算法在帧内能有效地划分感兴趣区域，压缩率在30以上，峰值信噪比在42dB以上，目标无失真；帧间压缩的压缩率在7左右，背景区域有误差累积，但整体图像的峰值信噪比都在40dB以上，目标无失真。

Accordingly pels tracing and function approximation are avoided ,and vectorization process is simplified effectively.At first ,every arithmetic of image transformation and image filter is researched and its disposal image is analyzed .

本文首先对图像变换和图像滤波的各种算法进行了研究，分析了各个算法的处理效果，根据实验试验结果提出应结合图像本身的特点选择合适的预处理方法，并运用小波变换对图像进行压缩变换和滤波处理。

In addition, the new compression method is simple, and the memory requirement in the operation process is lower, and it is fit for parallel optimizing progress. The compression speed can be advanced by using DSP, and it also can be implement image real time compression with little information loses.

另外，该压缩方法运算过程中所需存储量小和算法简单的特点，适宜硬件实现，而且便于并行处理，如果用数字信号处理器实现压缩算法，可进一步提高压缩速度，实现用于图像数据在高保真情况下的实时压缩。

A great deal of experimental results are presented, proving that the digital watermark generated by the algorithm is unperceivable and shows great robustness to the common image processing like low-pass filtering, median filtering, Wiener filtering, nosing, cropping, rotation and JPEG loss compression, etc.

大量的实验结果表明，用本算法产生的数字水印能保证数字图像的不可见性，并且对常见图像处理均具有很好的鲁棒性，主要表现在低通滤波、中值滤波、维纳滤波、图像加噪，图像裁剪、图像旋转和有损JPEG压缩处理。

The result of simulation shows that the compressing ratio of this method is superior than that of other conventional methods, and so is the image decompressing quality.

仿真实验结果说明，该方法在同等图像的恢复质量下，其压缩比优于传统的压缩方法，在提高图像的恢复质量方面也有一定价值。

Gurman wrote,ìWhat you're seeing is the difference between "beacon mode"(near real-time, heavily compressed, binned [I believe 512 x 512 or smaller]) images and normal playback telemetry images (2048 x 2048 native mode, less heavily but still lossily compressed).

博士Gurman说，ìWhat你看到的是区别&灯塔模式&（近实时，大量压缩，结合了出色的[我相信，512 × 512或更小]）图像和正常播放遥测图像（2048 × 2048本机模式，量较低，但仍然lossily压缩）。

The huge challenge in digital image and video sequence is the great amount of data, which should be compressed and decompressed in practical work.

数字图像视频的突出问题在于庞大的数据量给存储和传输带来困难，因此数字图像视频的处理离不开压缩和解压缩技术。

For example, the object is composed of four blocks, i.e. block A, B, C, D. Block A locates the left of block B and above block C. According to order, its code is ABDC etc. This code does not change its order after the object rotates, zoom, downsizes. The disadvantage of this method is that it will lose the target when the color is changed.A video fluid is composed of compressed data which include I, P and B(bi-prediction) frame. The data of each block of P frame is predicted by motion prediction and compensation from the data and motion vector of I frame.

MPEG视频流由I、P、B组成，为减少空间、时间的冗余，P帧的数据来自已经解压缩的I帧和P帧，B帧的数据来自已经解压缩的I帧和P帧或者P帧和P帧，这些需要解码的图像通过运动预测和补偿对P帧／B帧进行解码，P帧／B帧中每一个宏块的数据来自于最佳匹配的相应I帧和P帧或者P帧和P帧中，以及图像变化而必须的运动补偿。

The basic theory of remote watching system for an unmanned substation is introduced. The necessity of image compaction in dada transmission, the theory of 2?dimension wavelet transform, and Mallat algorithm are also explained. Based on that, the method for reconstituting the site image with the original picture and the effective area,which is compacted by the wavelet transform and transmitted to dispatch center, is analyzed.

介绍了无人值守变电站遥视系统的基本组成原理，阐明了压缩传输图像的必要性，论述了二维小波变换的原理与Mallat算法，在此基础上，着重分析了利用二维小波变换压缩传递图像的有效区域并传至调度中心与底图重构出现场实况的方法。

On the basis of analyzing characteristic of multispectral images, IHS transform and integer wavelet transform were combined to compress data.

提出了一种有效的多光谱遥感图像有损压缩算法，该算法根据多光谱遥感图像的数据特点，将IHS变换和整数小波变换相结合进行数据压缩。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。