Help me understand WHY DVR manufacturers still uses G.711 mu

[FranciscoNET 0]

Hi,

 

I own a HiKVision HD-TVI 8 CH Standalone DVR that I purchased not only to upgrade my own house's Standard Definition system that I build more than 10 years ago but to see how good these DVRs are before I use them as my new default standard for all of my customer installations as a way to finally move to the full HD standard and I have been very happy with this system, lots of features, stability and most importantly for me, all recording are done using the .mp4 one of a standard video format that VLC, Media Player Classic from KLite Codec Packs, Windows Media Player, etc is capable of playing without having to use a proprietary player executable in order to play them even through HiKVision still does provide a video player executable to playback your downloaded from the DVR videos, its not needed in order to see the video.

 

So, everything is great, great video format (.mp4) without requiring any conversions. You download the videos using the IVMS client and within 2 minutes you get 3 hours worth of footage all in .mp4, GREAT! Just want I wanted to see in a decent DVR.

 

My complaint is, why all DVR manufacturers are still using that ancient outdated G.711 mulaw audio codec for users that needs to record using a microphone? Look, the industry went thru the hassle of upgrading to the High Definition video standard, did all kinds of optimizations in order to ensure that the video looks as beautiful and crisp as that of my TV cable box, we have three major standards which they are HD-TVI (1st place), HD-CVI by Dahua (2nd Place) and finally the older HD-SDi (3rd Place) not counting of course IP Cameras but where they did drop the ball was not upgrading the ancient G.711 audio standard from the Bell Systems 1980's invention to something more decent like mp3 or even the completely open source ogg compressed audio standard.

 

Lets see a few technical analysis of the ancient G.711 audio codec:

Disk space requirements: 20 Kilo BYTES per second, that translates to 1.2 Mega Bytes per minutes or 72,000 KB (70.3135 MB) per hour.

 

Now, lets see how MP3 does:

128 kbps at a sample rate of 44.8 khz, Stereo takes 48 MB per Hour, but we dont need Stereo when we will be using just one full range microphone so: 128 kbps at a sample rate of 44.8 khz MONO (Monaural) can take as little as 24 MB per Hour and provided that you used a full range microphone you get crystal clear voice recordings just like you get crystal clear video recordings when done at 1080p HD, compare that to G.711's 70 MB per hour and you dont even get audio past the 11,000 Hz frequency response and people's "s" sounds like if they are "spraying it".

 

Now, suppose you have trouble with spending 24 MB per hour on the audio recordings, you can still downgrade the mp3 or ogg bit-rate to something like 96 kbps at a sample rate of 22.4 KHz, mono and the disk space requirements would be aound 8 to 12 MB per hours and the audio would still sound infinitely better than G.711's 8 KHz sample rate at 64kbps wasting 70 Mega Bytes per Hour.

 

WHY haven't the DVR manufacturers considered the mp3 or the open source freeware OGG properly compressed audio standard? A DVR that does production quality full HD recording shouldn't be paired with G.711 as the only selectable codec there. This is wrong and this needs to be fixed. If they want to leave G.711 as an option fine, but provide other options too such as MP3/ogg with a variety of bit-rate options for the customer to DECIDE. A good full range microphone can give you crystal clear recordings and make your evidence really stand out specially when what's being said is paramount to a case.