| 摘要 |
PURPOSE:To improve the data compression efficiency by coding separately data inverted or non-inverted at each line from a picture data read in line unit respectively, and adopting the coded data in a less amount to compress the data. CONSTITUTION:A black-and-white signal of a picture read at each line is binary- coded at each picture element at a reading control section 11 and inputted to a data compression section 12. The picture data at each line is inputted to a coding circuit 15 while being subject to no inversion and inverted at an inverting circuit 14 and inputted in parallel to a coding circuit 16. An amount of data subjected respectively to linear run length coding at the circuits 15 and 16 is compared at a comparison selecting circuit 17, the data with a less amount is selected and transmitted to a data transmission section 18 together with information for discriminating non-inverting and inverting. A data resoring section 20 at the receiving side detects a line identification code of data, non-inverting/ inverting identification code of the data received 23, processes a compressed data for decoding 24 with expansion and when the non-inverting code is received, the decoded data is outputted as it is and when the inverting code is received, the decoded data is inverted and outputted from inversion circuit 25. |
