| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent lost frames so as to realize a monitoring operation of high reliability. SOLUTION: Image signals outputted from a monitoring camera 12 are digitized by a decoder 18, and the digitized image signals are subjected to YUV conversion and then inputted into a compression/expansion circuit 30 via an image memory 28. The compression/expansion circuit 30 compresses the inputted image data through a JPEG mode, and the compressed image data are stored on a hard disk 32 through an image memory 28. A CPU 26 changes the compression rate of the compression/expansion circuit 30 so as to reduce the compressed image data to a prescribed size or below. When the compressed image data are not reduced to a prescribed size even after compression is repeatedly carried out, some of the compressed image data are eliminated to forcibly reduce the compressed image data to a prescribed size or below so as to surely fetch in the following image data, and a compressed image file from which some of the compressed image data are eliminated is recorded on the hard disk 32.</p> |
