August 9, 2014
When searching for standalone Digital Video Recorder (DVR) or Network Video Recorder (NVR) you will see QCIF, CIF, 4CIF, D1, 960H parameters in every standalone DVR /NVR technical information table. CIF, 4CIF, D1, 960H are the recording and playback resolution for security DVR while it’s often 720p and 1080p for NVRs. These parameters are important factors in determining the video recording surveillance resolution quality of a DVR or NVR .
What’s CIF ?
CIF is the abbreviation of Common Intermediate Format. CIF=360x240pixels
CIF format with follow features:
- The resolution is suitable for video home system (VHS), with resolution 360x240pixels
- Adopted non-interlaced scan
- Using NTSC, play video maximum frame rate at 30 000/1001≈29.97fps/second
- PAL tv system, resolution reach up to 288 tv lines.
- CIF format is an old standard for video surveillance system
What is D1 ?
In cctv system industry, everybody knows D1 is the resoltuion of recording, playback and display resolution. Actaully it’s not ture. D1 is a digital tv system standard format, it is divided into the following categories:
D1: 480i format (525i): 720×480 (resolution 480tv lines, Interlaced), and NTSC tv system with same resolution, Line frequency 15.25kHz, the equivalent of what we call 4CIF (720 × 576).
D2: 480P format (525p), 720×480 (resolution 480tv, progressive scan), with more clear compared to the D1 interlaced, is e the equivalent of DVD resolution.
D3: 1080i format (1125i): 1920×1080 (resolution 1080 tv lines, interlaced scan), high definition video format, resolution 1920x1080i/60Hz, Line frequency 33.75kHz.
D4: 720P format (750p), 1280×720 (horizontal resolution 720 tv lines, progressive scan), a low resolution compared to D3, but with reason of progressive scan, many people feel D3 is more clear than D4, especially when display the characters, resolution 1280x720p/60Hz, line frequency 45kHz.
D5: 1080P format (1125P), 1920×1080 (horizontal resolution 1080tv lines, progressive scan), the highest standard resolution in tv system, resolution 1920x1080P/60Hz, line frequency 67.5KHz.
960H introduction
960H products are firstly intruced by Techwell and Sony, among analog security camera adopts sony new generation 960H CCD image sensor. Now, many security manufacturers begin to launch 960H series products for security solution. The 960H high definith analog camera adopts 960H CCD plus Effio DSP, offering high resolution, low noise and true color video footatge.
With development of 960H security camera, 960H DVR is coming into market. Only using 960H security camera and 960H DVR can build up a high definition 960H video surveillance system. 960H DVR can recording the video at 700 tv lines. It’s compatible with 700 tv lines 960H security cameras. The 960H DVR offer high definition quality video both in real-time recording, viewing, playback.
Additionally, 960H resolution is 960×582, it’s one quarter of 1080P resolution. So the 960H system can switch to 1080P system smoothly. Last, 960H security camera is the analog camera, transmitting video without delay, image resolution without coding or decoding, so the video footage more clear.
Please note: 960H resolution is also called as wide D1 resolution (WD1), that means WD1 = 960H.
