In the process of saving the images from the buffer memory to the SD card, the JDR system saves image files to the SD card as soon as the buffer memory processes its information. Collected images files are become the video files at SD card. Thus JDR system doesn’t allow recording failure in an accident such as power off. On the other hand, buffer memory in other file systems takes time to collect and put the images together until making up a single video file. Once the buffer memory combined it and out put a video file, then it moves to SD card. Since buffer memory is volatile memory, any information on the memory can be dissapear when there is an impact, damages or power shut down etc.