Vorrichtung zur Kontrolle der Datenmenge und Kodierer dieselbige anwendend

摘要

The invention is directed to provide a code-amount control device for use in video-coding device, which controls the generated code-amount of each block (block length) after variable-length coding in the video-coding process to surely be less than the designated target code-amount. The code amount control device is provided with a rate control circuit (11) for setting a target code-amount of each of blocks to be encoded, a rounding circuit (7) for converting a sequence of quantized values into a set of the number of continuous zeroes and following thereto non-zero quantized values and a code-length table (8) containing variable code-length values to be allocated to respective sets of the number of continuous zeroes and non-zero values. Before variable-length encoding of the image block, the rounding circuit (7) estimates by accumulating the code length of each block with reference to the code-length table (8) and outputs the quantized values as they are to a variable-length coding circuit (9) when the accumulated code-length does not exceed the target code-amount. If the estimated code-length exceeds the target code-amount, the rounding circuit (7) outputs the quantized values after rounding off the excessive portion thereof. <IMAGE>