Brief Analysis of key technology of HD IP Camera

Brief Analysis of key technology of HD IP Camera
HD network camera usually its resolution is the number of pixels of different but with different specifications and classification, in practical applications, depending on the needs of the environment, the product characteristics also have different requirements, so in addition to many mega pixels exceptionally, in accordance with the main features of the classification of the other, if applicable, the shading varied scenes wide dynamic camera, suitable for low-light cameras in low-light environments, suitable for special high-risk active early warning surveillance applications Intelligent Video Analysis camera and so on.
An image sensor
HD network camera as a camera, you must have the camera key technology areas, such as sensors (Sensor technology). Sensor link as the most distal end of the optical signal is converted into an electrical signal, the key technology is most directly affect the image quality of the camera. HD network camera, this is no exception, and the sensor has applications in high-definition network camera on the specific requirements need to be able to meet the high-definition image uptake required a large amount of data processing capabilities, as well as required to meet the high-definition large-format image large the target surface, which gave the high-definition IP camera sensor technology, which brings the cost pressures and technical challenges.
Sensor types of commonly used both CCD and CMOS analog cameras common CCD sensor, but to the high-definition era, we can find the application of the CCD is very small, if 720P-level HD camcorder can see CCD, 1080P-level HD camcorder, almost all of CMOS products. Most HD cameras are based CMOS sensor is very simple, high-definition large amount of data processing power CMOS has the absolute advantage, while CCD meet the the HD application of a substantial increase in manufacturing costs, the key benefit from CMOS technology in recent years leaps and bounds, previously limited low-light video effects, wide dynamic problems can be solved gradually, etc., coupled with the CMOS inherent cost advantages make it to occupy the mainstream position in the field of HD IP Camera.
Video compression algorithm
Another key technical aspects of the HD IP Camera is the video compression algorithm, video images transmitted by the network after digital compression This is the most basic functions of the network cameras, video compression algorithm is better than the poor directly determines the quality of the video image. Can be viewed from two perspectives, on the one hand, a good video compression algorithm, you can minimize the distortion of the picture, it is well known video compression are lossy compression used in network transmission, information on the screen is bound to lose, so necessary maximum in the case of compression ratio to meet the retained most of the information on the screen; case the other hand, video compression algorithm, and can provide a better picture of the effect, using a lower bitrate means occupy more low bandwidth and less storage space.
Mainstream applications of video compression algorithm for H.264 standard, H.264 defines four different profile (class / level) Baseline (Baseline), Main (class), Extended (extended class) and High Profile (high profile), the higher the level of the same quality the smaller the bit rate, the greater the intensity calculation. With the growing demand of high-definition applications, video compression algorithm upgrade footsteps did not stop, the upcoming H.264 standard is widely used at the same time, the H.265 standard. June 25, 2012, the International Telecommunication Union (ITU) announced on its official website a work plan for the project, originally scheduled for 2008-2010, "High efficiency video coding" (HEVC, or H.265) standards are expected was launched in January 2013. H.265 algorithm standard video compression efficiency than H.264 doubling that guarantee the same video image quality under the premise of the video stream bit rate reduction of 50% can be achieved to 2Mbps transmission speed transmission 720P, a The saving of the network bandwidth, the other to save video storage space, application greatly reduces the cost of the high-definition camera.
The launch of the H.265 standard will give the development of HD IP Camera and even high-definition surveillance market would do things differently, remains to be seen, I believe that the short-term or will not change much, the key depends on the degree of follow-up of the chip maker, everything goes according to plan road, H.265 brought the change in the earliest by the end of 2013 or even 2014 to see.
Wide dynamic
In addition, to meet a variety of application scenarios and high-definition monitor building programs, where the key features of a wide dynamic is also a HD IP Camera. A lot of applications are backlit scene contrasty larger area, if it is to look at the light and in the dark, you need a camera with wide dynamic effect, in order to ensure that is too bright and too dark at all be able to see
Initiative to enhance video
The effective combination of the stream and the picture quality is also key. HD video requires high bit rate, bit rate reduction to mean sacrificing picture quality, in order to high quality picture, you need a higher bit rate. So is there a way that can guarantee the bit rate is not increased, to ensure that key picture quality, the answer is yes. The VAE (video Active Enhancement) video initiative enhanced, allowing different regions of the video screen to enjoy quality encoding treatment, perhaps only part of the so-called good steel should be used wisely, the whole lot of the video screen we focus on the region, that we let the limited video coding resources focus in this part of the region, focused on enhancing the clarity of the region of interest, due to lower non-key areas clarity, improved target definition, without increasing the network load can be described as a win-win.
Three-stream
With the increasing demand of mobile monitoring, the limited bandwidth resources of the high-definition IP Camera with high-definition video and high-bit rate mobile monitoring the formation of a contradiction, it was proposed to use dual-stream, yes, but here dual-stream can no longer meet needs, the overall high-definition monitor solve the program, the HD IP Camera must bear all the way to high-definition video for video storage, while providing a signpost definition video for remote monitoring, this dual-stream, on this basis, the high-definition camera must support three yards stream third way stream dedicated to mobile monitoring can be lower resolution and bit-rate video monitor required to meet the needs of mobile phones and mobile devices, three stream is complete HD overall solution must have
Smart technology
HD network camera brings high-definition video quality, video surveillance into the HD era, but did not change the traditional passive monitoring mode. High-definition image of the site can make monitoring more clearly, but can not change many key observation of the monitoring site, easy to miss a passive state. And then clear the screen, if not alarm occurs when the first time to monitor staff see its effective value will be greatly reduced. Therefore, the combination of HD and intelligence is the most effective weapon, the use of intelligent video analysis, early warning effect, the first time there will be police intelligence, high-definition screen pop, will greatly enhance the efficiency of its monitoring.
In the era of traditional analog cameras monitoring camera itself does not have video processing DSP chip can not be intelligent video analysis algorithms embedded into the camera, in order to achieve the intelligent monitoring, additional intelligent video analysis equipment, cost and maintenance effort are larger. The emergence of HD IP Camera has its own video processing DSP chip, so you can achieve the intelligent video analysis algorithm is embedded into the high-definition camera. On the one hand can be intelligent video analysis technology applications in high-definition screen, to ensure the accuracy of the intelligence analysis, the more traditional image of the SD or lower resolution intelligent analysis in terms of accuracy enhance large conceivable; On the other hand reduces the need to of additional intelligent analysis equipment costs, reducing the overall cost of the monitoring program.
Epilogue
HD network camera is facing many problems to be solved, such as the pressure of high bit-rate bandwidth, storage pressure, high-definition lens in the actual project selection and cost issues. At present, the application of HD IP Camera is still in its early stages, many problems with the technology continues to evolve, gradually crack, high-definition monitor becomes easier, HD IP Camera market will quickly zoom.
From:http://www.vstarcam.com/channel/Brief-Analysis-of-key-technology-of-HD-IP-Camera-60.html