| 摘要 |
<p>PROBLEM TO BE SOLVED: To uniformize encoding efficiency in a screen in a picture encoding device which compresses picture data. SOLUTION: A block division processing circuit 32 divides picture data from an input terminal 3 into unit blocks of an orthogonal transformation. A mask processing circuit 36 masks an output of the circuit 32 with a block unit in accordance with a mask selection signal from an input terminal 34. A DCT processing circuit 38 discrete cosine converts an output of the circuit 36. A code amount estimation circuit 40 collects outputs of the circuit 38 for N blocks and estimates quantization characteristics so that the code amount after variable length encoding is within a specified range. A quantization circuit 42 quantizes output data of the circuit 38 and a variable length encoding circuit 44 variable length encodes output data of the circuit 42. A block to be masked by the circuit 36 vertically reduces a picture angle of the inputted picture signal and has it selected so that a rate of the number of blocks to be masked in N blocks, which becomes an estimation unit of the circuit 40, becomes almost uniform over the whole inputted picture signals.</p> |
