Image data demodulation apparatus and method thereof

An optical disk data reading apparatus comprising:

• input control means for controlling an input of an encoded image data;
• detecting means for detecting a sequence header from the encoded image data supplied from the input control means and outputting an input stop signal if the sequence header is detected;
• delaying means for delaying the encoded image data supplied from the input control means;
• extracting means for, when the detecting means detects the sequence header from the encoded image data supplied from the input control means, extracting a data corresponding to an image type from the encoded image data delayed by the delaying means;
• storage means for storing the encoded image data supplied from the delaying means in a first region in a memory region, the memory region having a predetermined buffer size;
• control means for controlling the input control means to interrupt the input of the encoded image data corresponding to the input stop signal, calculating a buffer size necessary for demodulating the encoded image data based on the data corresponding to the image type extracted by the extracting means, comparing the calculated buffer size with the predetermined buffer size and when the calculated buffer size and the predetermined buffer size in the storage means is different, after the encoded image data stored in the current memory region is read out and the current memory region is released, securing a second region in the memory region, and controlling the input control means so as to restart the input of data into the second region;
• and
• demodulation means for demodulating the encoded image data stored in the memory region.

An image data demodulation method comprising:

• controlling an input of an encoded image data;
• detecting a sequence header from the inputted encoded image data, and outputting an input stop signal if the sequence header is detected;
• delaying the inputted encoded image data;
• extracting a data corresponding to an image type from the delayed encoded image data, when the sequence header is detected from the inputted encoded image data;
• storing the delayed encoded image data in a first region in a memory region, the memory region having a predetermined buffer size;
• controlling the input controlling to interrupt the input of the encoded image data corresponding to the input stop signal, calculating a buffer size necessary for demodulating the encoded image data based on the data corresponding to the extracted image type, comparing the calculated buffer size with the predetermined buffer size and when the calculated buffer size and the predetermined buffer size of the first region is different, after the encoded image data stored in the current memory region are read out and the current memory region is released, securing a second region in the memory region, and controlling the input so as to restart the input of data into the second region;
• and
• demodulating the encoded image data stored in the memory region.