Dahua uses 1000kB/s HikVision uses 2000kB/s?

[TomBowyer99]

Hi,
I have 5 Dahua IPC-T5442TM-AS 2.8MM, purchased from Andy, which are superb, however I wanted to give full colour night vision a try so I have just installed a Hikvision DS-2CD2347G1-LU 2.8MM

I immediately notice that under exactly the same conditions (cam-garden and cam-rear2 in the same place facing the same direction) the bitrate of the Dahua is around 1000kB/s but the Hikvision is around double, 2000kB/s.





I "think" both are configured the same:

HikVision:



Dahua:


The "Max Bit Rate" of the Hikvision allows me to put a higher value (16384 as opposed to the Dahua at 8192), but both of those figures are way higher than is being sent so I doubt that would cause the bitrate to double)?

Does anyone know why the Hikvision, with the same settings, showing the same picture at the same quality/resolution etc (and the picture of both looks identical in quality to my eyes), would use double the bandwidth? Does Blue Iris treat these streams differently or something?

Thanks,
Tom.

 

[TomBowyer99]

Ok found the source - it's the "Max Bit Rate" that does it. If I set the Hikvision Max Bit Rate to 8192, the same as the Dahua, the bit rates are now the same:



But I dont get it - both 8192kbps and 16384kbps are way higher than 2000 kB/s?

EDIT: Ok - i'm an idiot:



Total confusion on Kilobit per second vs Kilobyte per second...

Urgh.

 

[TomBowyer99]

One more question though - with the Dahua at 8192 and the Hikvision at 16384 (both variable bit rate) - the pictures look identical - no difference in quality at all that I can tell. So why would the Hikvision use double the bandwidth?