Compression and expansion methods and apparatus
    2.
    发明授权
    Compression and expansion methods and apparatus 失效
    压缩膨胀方法和装置

    公开(公告)号:US6061473A

    公开(公告)日:2000-05-09

    申请号:US844528

    申请日:1997-04-18

    CPC分类号: G06T9/00

    摘要: A compression and encoding system for bi-level image data determines the available memory capacity of a receiving device, then compresses and encodes the image data with successively increasing compression ratios until encoded data not exceeding the memory capacity of the receiving device are obtained. Preferably, the image is divided into rectangular blocks, and successive bit planes are generated on the basis of the number of dark picture elements in each block, and on the basis of adjacency relationships among like-valued picture elements in each block. Feedback may be employed to adjust the darkness of certain compressed blocks according to the darkness of the preceding block.

    摘要翻译: 用于双电平图像数据的压缩和编码系统确定接收设备的可用存储器容量,然后以连续增加的压缩比压缩和编码图像数据,直到获得不超过接收设备的存储器容量的编码数据。 优选地,图像被划分为矩形块,并且基于每个块中的暗像素的数量,并且基于每个块中的相似值的像素之间的相邻关系来生成连续的位平面。 可以使用反馈来根据前一块的黑暗来调整某些压缩块的黑暗。