Thomson Consumer Electron., Indianapolis, IN.
IEEE Trans Image Process. 1995;4(5):533-42. doi: 10.1109/83.382489.
We present an algorithm to conceal bit errors in still images and image sequences that are coded using the discrete cosine transform (DCT) and variable length codes (VLCs). No modification is necessary to an existing encoder, and no additional bit rate is required. The concealment algorithm is kept simple so that real-time decoding and concealment is possible. A single bit error in these images can cause a block to split into several blocks or several blocks to merge into one. This causes the DCT coefficients of all subsequent blocks to be correctly decoded but stored in the wrong location in the image. Furthermore, the DC coefficient of all subsequent blocks may be incorrect. The error concealment algorithm uses transform domain information to identify the location of the affected blocks and to correct errors. The image quality after error concealment is shown to be significantly improved.
我们提出了一种算法，用于隐藏使用离散余弦变换（DCT）和变长码（VLC）编码的静态图像和图像序列中的位错误。无需对现有编码器进行任何修改，也不需要额外的比特率。隐藏算法保持简单，以便实现实时解码和隐藏。这些图像中的单个位错误可能导致一个块分成几个块，或者几个块合并成一个块。这会导致所有后续块的 DCT 系数被正确解码，但存储在图像中的错误位置。此外，所有后续块的 DC 系数可能不正确。错误隐藏算法使用变换域信息来识别受影响块的位置并纠正错误。显示错误隐藏后的图像质量得到了显著改善。
