What is the relationship between frame size, sequence size and the number of frames recorded?
Frame size refers to the size of a raw camera frame. Keep in mind that the CLFC uses “perfect” bit-packing, so a 10-bit 1024×1024 image is only 1,310,720 bytes. The frame size may range from a few kilobytes to tens of megabytes, however disk-write operations are optimized for roughly 3.5 MB. To ensure maximum record bandwidth, camera frames are either merged or split so that the optimal size write can be performed. A single disk write operation is called a “sequence”. Consider two cases. Case 1: A camera has a 1.25 MB frame, split across 4 channels. The size per channel is 327680 bytes. Therefore, 11 frames will be combined into each sequence. Case 2: A camera has a 16 MB frame, recording to 1 channel. The frame will be split into 5 3.5 MB frames (the last being only partially used). When a frame is split into multiple sequences, we call this “fragmented” or “multi” writes. Many DVR Express operations must be aligned to sequence boundaries. In the fragmented case, this does not restric
