HIKVISION H.265+ Encoding Technology Halve Your Bandwidth and Storage Enjoy the Ultra HD and Fluency

1. BACKGROUND Several years ago, the ultra HD surveillance camera was developed. However it has not been widely applied so far because it requires wide transmission bandwidth and massive storage capacity. Thus, how to limit the bitrate of the ultra HD video stream becomes a critical problem that decides the ultra-HD camera popularity. H.265+ technology is an intelligent algorithm developed by Hikvision. It is a remarkable encoding technology based on the H.265/HEVC (High Efficiency Video Coding) standard and is optimized while fully considering the following features of the surveillance video....

frame prediction encoding. 2.1.1. P-FRAME ENCODING With inter-prediction, you can lower the bitrate by compressing only the difference between the current frame and the reference frame. Therefore, selecting an appropriate reference frame is the key to improving the stream compression ratio. For a surveillance video, the background information is usually stable. Thus, we can extract a background frame as a reference frame to encode. The background frame should contain as few moving objects as possible. As shown in Figure 1, among the three frames, T0 and T1 are the encoded images. You can take...

Reference frame Residual part Final image Figure 3 Ordinary Reference Type Example 2: However, if we take only the background frame (T0) as the reference frame, we can find a block that is almost the same as the B area, while the A area is a new area. Then it will cost more bits when encoding the A area. Example 3: Moreover, if we take the background frame and T1 as the reference frames, we can simply find the areas that are similar with the A area and B area. Then the bit cost can be reduced to the lowest value. T0 T2 T1 Residual part (less data) Final image Reference frames Figure 4 Background...

Chosen by intelligent analysis I-Frame (Background frame) I-Frame (Background frame) Figure 5 Prediction Encoding Reference Relationship Frame Type I-Frame (Background Frame) I-frame is completely encoded based on the current image adopting the intra-frame prediction encoding. that is chosen by the intelligent algorithm and contains as few moving objects as possible. The R-frame adopts intra-frame prediction encoding (for moving objects) and inter-frame prediction encoding based on I-frame (for motionless objects). The R-frame works as I-frame in the video stream during the random access to guarantee...

Intra-frame prediction encoded moving objects Moving objects Inter-frame prediction encoded motionless objects Final image Background image Residual part Motionless image Figure 6 R-Frame Mixed Prediction Encoding 2.2. NOISE SUPPRESSION Normally, in order to guarantee the quality of the moving objects, the encoding module also encodes the noise in the environment. But now, with the intelligent analysis algorithm that can distinguish between the background image and the moving objects, the moving objects and the background can be encoded with different encoding strategies. As shown in Figure 7,...

as 0:00 to 9:00 and 20:00 to 24:00 in the office), as shown in the below diagram (we take the constant bitrate control as the example). Bitrate Figure 8 The Bitrate Control of the Constant Bitrate  Constant Bitrate Control For H.265 encoding with the bitrate configured as constant, the bitrate slightly varies near the predefined Max. bitrate value. With H.265+ on, the average bitrate can be kept as the half value of the Max. bitrate (take the office surveillance as the example, the actual bitrate reduction rate may vary with different surveillance scenes) and the image quality can be optimized...

3.1. INSTANT BITRATE OF DIFFERENT SCENES Table 1 Instant Bitrate Comparison between H.264 and Hikvision H.265+ No. Scene Description Cafe, Sufficient Illumination, Many Moving Objects Cafe, Sufficient Illumination, A Few Moving Objects Cafe, Low Illuminated (IR On), Motionless Street, Sufficient Illumination, Many Moving Objects Street, Sufficient Illumination, A Few Moving Objects Street, Low Illuminated, Motionless Bitrate (kbps) Average Decreased Rate Table 2 Instant Bitrate Comparison between H.265 and Hikvision H.265+ No. Scene Description Cafe, Sufficient Illumination, Many Moving Objects...

3.2. 24-HOUR FILE SIZE OF DIFFERENT SCENES  Scene 1: Café Table 3 24-Hour File Size Comparison - Café Average Bitrate (kbps) Theoretical File Size in 24 Hours (GB) File Size Comparison between H.264, H.265 and Hikvision H.265+ H.264, 83.00% Decreased Rate Hikvision H.265+ Decreased Rate Figure 9 Comparison Chart - Café  Scene 2: Intersection Table 4 24-Hour File Size Comparison - Intersection Time Average Bitrate (kbps) H.264 Theoretical File Size in 24 Hours (GB)

File Size Comparison between H.264, H.265 and Hikvision H.265+ 40 Decreased Rate Decreased Rate Figure 10 Comparison Chart - Intersection Conclusion: For the café monitoring, the decreased rate of the 24-hour file size between H.264 and Hikvision H.265+ is 83.0 percent, and the rate between H.265 and Hikvision H.265+ is 67.3 percent. For the intersection monitoring, the decreased rate of the 24-hour file size between H.264 and Hikvision H.265+ is 79.4 percent, and the rate between H.265 and Hikvision H.265+ is 64.5 percent. Hikvision H.265+ can greatly decrease the file size in the all-day monitoring...