Relationship between audio and video parameters and traffic

Currently, there are four common types of networks: ADSL dial-up access, optical fiber access, 3G dial-up access, and LAN. Mobile terminals are concerned about the relationship between our video parameters and traffic because of traffic fees and the smoothness of Video Chats: next we will take the encoding standard in anychat, a relatively mature mobile video development kit, as an example to analyze video quality and bandwidth issues in detail. You can also download the software to test it yourself.

 

ADSL dial-up access is an asymmetric network access. The downstream traffic is usually 2 Mbps, 4 Mbps, and 6 Mbps, while the upstream traffic is usually 512 kbps, that is, the uplink and downlink speeds are asymmetrical. If you need to use anychat for audio and video interaction, the upload traffic can only use 320 kbps as the reference value. The suitable resolutions include qvga (240x352) and CIF (288 X) VGA (640x480 ).

 

The optical fiber access method is a symmetric network access method. The uplink speed is usually the same as the downlink speed. The optical fiber access network is usually very stable and suitable for transmitting high-quality videos. When the network bandwidth permits, the suitable resolution is qvga (320x240), CIF (352x288), VGA (640x480), svga (800x600), 720 p (1280x720 ).

 

3G dial-up access is also an asymmetric network access. Different network operators provide different network bandwidths, and the same uplink bandwidth as ADSL is much lower than the downlink bandwidth, for example, the 7.2mbps network bandwidth advertised by China Unicom 3G refers to the downstream bandwidth, and the quality of the 3G network bandwidth is related to the location. The closer the signal base station is, the better the quality, the fewer 3G users that use the same base station, the better the quality. In this access mode, the suitable upload resolutions include qvga (320x240) and CIF (352x288 ).

 

The LAN or private network bandwidth is abundant. The resolution depends on the performance of the PC. Generally, the LAN can be CIF (352x288) or VGA (640x480) svga (800x600), 720 p (1280x720), and other resolutions.

 

Anychat quality mode resolution and Bit Rate Table (unit: Kbps)

	320x240		352x288		640x480		800x600		1280x720
	12fps	25fps	12fps	25fps	12fps	25fps	12fps	25fps	12fps	25fps
Static	20	40	60	70	100	130	160	180	350	380
Motion	150	200	210	250	400	450	550	650	850	900
AVG	80	120	150	180	200	230	300	350	450	550

Static-static screen, motion-Motion Image peak, AGV-average bit rate

 

The video quality of anychat can be divided into "Bit Rate Control Mode" and "Quality Control Mode". In "Bit Rate Control Mode", the target bit rate of the Video Stream fluctuates up and down with the set bit rate, in the "Quality Control Mode", the target bit rate is automatically adjusted according to the video image motion scenario. When the static screen is used, the lower bit rate is output, while when the motion picture is used, A high bit rate is output to ensure that the video details are displayed. Generally, the "Quality Control Mode" can be used in scenarios with ample network bandwidth, such as optical fiber access methods and local area networks ", the "Bit Rate Control Mode" is suitable for ADSL dial-up access and 3G dial-up access.

 

For the frame rate of a video, the higher the frame rate, the smoother the video, the higher the network pressure, and the higher the output bit rate. Generally, high frame rate can be used in scenarios with ample network bandwidth such as optical fiber access mode and LAN, such as 20 FPS and 25 FPS, while low frame rate is suitable for ADSL dial-up access and 3G dial-up access, such as 8fps and 12fps.

Relationship between audio and video parameters and traffic