HD IP Camera monitoring knowledge

HD IP Camera monitoring knowledge
Megapixel slowly boarded the security monitoring application stage, you understand HD? Million high-definition camera, transmission, storage to the display, you understand millions of high-definition surveillance system constitute:
Q: What is 720P? What is 1080p?
A: 720P, 1080P is the Film and Television Engineers (SMPTE) to develop the highest level of high-definition digital TV format standard 720P effective display format: 1280 x 720 pixels 921,600 1080P effective display format is: 1920 × 1080 pixel number 2073600. SMPTE (American Film and Television Engineering Association) different digital high-definition signal digital television scan lines divided into 1080P, 1080i, 720P (i interlace interlaced, p is the meaning of the Progressive, Progressive). 720P, 1080P is a progressive scan 1280 × 720,1920 × 1080 resolution display format. The integration of digital cinema imaging technology and computer technology. We often say 720P HD camera 1080P HD camera is in accordance with this standard, through the video image capture, encoding, compression, decoding a series of processes the final output 720P or 1080P resolution image camera.
Q: What is the effective pixels for high-definition Network Camera?
A: the number of pixels of the digital video camera / camera effective pixels (Effective Pixels) and maximum pixel (Maximum Pixels). The type and maximum pixel number of active pixels is truly involved in the photosensitive imaging pixel value, the maximum pixel value is the real pixels of the photosensitive device, the data usually contains a non-image portion of the photosensitive device, and the effective pixels on the photosensitive device really involved in the light-sensitive part of the pixel value, it tends to be a lot less than the maximum pixel value, So, in the case of the same pixel area, digital camera / cameras can get the biggest image pixels is the effective pixels.
Many digital cameras / camera nominal pixel values ​​tend to be the maximum number of pixels, rather than the effective pixels. In addition, at the same time the effective pixels of the same photosensitive device used in shooting video and photographs is also different. The general effective pixels used in shooting video is much smaller than when taking pictures using the effective pixels.
Q: Viagra, as the dot-com HD IP Camera to teach you how to identify the performance of the HD IP Network Camera? (To nominal 720P/1080P camera how to be able to identify the pros and cons)
A: high-definition video surveillance camera belonging to something new, there is no uniform inspection and testing standards. Thus, although the same nominal 720P or 1080P HD video camera, but the gap on the visual senses is very obvious. We generally by the following five points to simply judge the pros and cons of high-definition IP camera
1, the intelligibility test
By ordinary video image resolution (number of lines) test card simply determine the clarity of high-definition video camera. This method can be distinguished by the naked eye directly to the sharpness of the image, general, 720P HD IP Camera test card indicators can clearly distinguish more than 800TVL TV lines, and poor high-definition camera of this indicator to be low, and image jitter or flash.
2, the dynamic range test
Gradation data can be Simple Analyzing HD images through the normal video image gradation test card.
3, color reproduction
Through the color testing card or the naked eye to determine the color reproduction of the comparison HD video image. Reduction of the general good HD IP Network Camera is very high, almost up to the very realistic reproduction.
4, the signal-to-noise ratio
The case of the same picture noise suppression processing is also a measure of an important indicator of performance advantages and disadvantages of high-definition IP Camera. For the screen dark blocks light and fast processing, the noise suppression directly determines the quality of the image, there are many low-end camera can only output is more clear picture of in the more than 100Lux the ideal state, the ability to adapt to the changes in the light environment poor light or dark light environment without an effective means for noise suppression, can not guarantee the quality of the image. High-definition image in this case does not make sense, which we call pseudo-HD.
5, the image compression coding algorithm
HD IP camera for image coding and compression algorithm and poor is also a direct impact on an important indicator of camera performance, high-definition camera on the market today coding of the camera video image processing chips into the DSP chip Qiu SIC chip two carriers, both strengths and weaknesses, DSP chips function application is relatively flexible, short development cycle, but the coding efficiency is low, and the cost is higher. ASIC chip features application is relatively fixed, long development cycle, but the high coding efficiency and the bulk lower cost. No matter what kind of carrier need a good video coding compression algorithm, a good algorithm to ensure image quality and clarity of the case as much as possible to reduce the video stream and storage capacity. The poor HD IP Cameras often mosaic or water ripples in the case of the large amount of exercise a direct impact on the quality of the video image.
Q: How to store high-definition images?
A: high-definition image storage devices and digital hard disk video recorder DVR (Digital Video Recoder), because it has a direct input digital video image, so it does not require coding for image compression, but only need to store digital video image data, in addition to Beyond this, it also needs to be able to support the management of HD IP Camera, network services, rights management, Web services and other back-end network services and application support. This equipment we are collectively referred to as the NVR (Net Video Recorder). NVR device in accordance with the different needs of a variety of product forms, including distributed NVR and centralized NVR storage system.
Q: how to display high-definition images?
A: At present most of the HD video image resolution of 720P (1280 * 720) or 1080P (1920 * 1080) mainly due to the resolution of even more than our traditional range of display capabilities of the display device in the display of high-definition images also introduces a number of new equipment, standards and interfaces. Including large-screen high-definition display, HDMI interface. Traditional digital display interface to the VGA standard, but the output resolution of the VGA standard interface can only achieve a resolution of 1280 * 1024, so when we need to show 1080P resolution HD image must be used with an HDMI standard interface for video signal transmission, support 1080P (FULL HD) resolution, high-definition display device for display.

From:http://www.vstarcam.com/channel/HD-IP-Camera-monitoring-knowledge-121.html