| 摘要 |
<p>PURPOSE: A differential image compressing method and a apparatus for the same are provided to increase a compression rate of whole image data by executing DCT to only a part different from a background color. CONSTITUTION: If color data is inputted, a first pixel is stored in a representative value table, and is set up as a reference pixel(510). An appropriate tolerance is decided to be fitted for color reaction sensitivity according to human viewing angle characteristics(520). The next pixel is compared with the reference pixel to judge whether the difference is in a range of the tolerance(530). If so, the next pixel is regarded as the reference, and the number of the references is increased(532). If not, a pixel in the range of the tolerance is searched for in pixels existing in the representative value table(540). If no pixel exists, the next pixel is stored in the representative value table in an ascending order(550). If the pixel exists, the next pixel is regarded as the representative value to be compared as a new reference(542). Representative values of the color data and related information are manufactured as a table(560). Representative values of the table are transformed through discrete cosine transform(DCT)(570).</p> |
