| 摘要 |
PURPOSE:To shorten the period of time required for data compression and encoding by compressing picture data, which is picked up in image at the time of exposure, during the objective exposure operation and determining a compression parameter of picture data obtained by the objective exposure in accordance with obtained data. CONSTITUTION:The same operation as conventional is performed till a time T4', and the objective exposure operation is started at the time T4', and simultaneously, the signal obtained by the pre-exposure operation is read out from a memory and is subjected to signal processing. DCT operation is performed from a time T5' to a time T6', and the first step of compression and encoding is performed from the time T6' to a time T8', and the objective exposure operation is terminated at a time T7'. Next, the exposure electric charge is read out from the time T8' to a time T9', and the signal processing of the actual exposure signal is performed from the time T9' to a time T10', and DCT operation is performed from the time T10' to a time T11', and the second step of compression and encoding is performed from the time T11 to a time T12. Compressed data is recorded on a memory card from the time T12' to a time T13'. Consequently, the time required for compression is shortened because the optimum quantization step for the exposure is obtained during the objective exposure operation based on data of previous exposure. |
