MPEG4

[qman 0]

What's the good thing about mpeg 4?

 

I have my mailbox full of offers by companies, mainly in taiwan and korea wanting to send me demos to distribute to the US.

 

CAre to explain anyone?

[cctv_down_under 0]

MPEG4 only records the moving bits in a movie stream, for example if a man walks by a house it might take 20 Frames to view it however the background will still be the same (if the camera is fixed) therefore there is no need to record the same background (the house) therefore you are only recording the man and he is overlayed onto the house picture background which is used 20 times as the same frame. Its not exactly like that but thats the gist of it, Basically it is a smaller file size and this technology allows for faster web demos as the frames that are transmitted arent as large in file size.

 

I hope this helped,

[DavidR 0]

DVR Expert nailed it. Its a better way of tranmitting AND recording video.

 

Practical example: in our SkyWire Video 2.0 product, with MJPEG we could get maybe 3fps on PocketPC using WiFi, and 1fps using a cell modem. With MPEG-4 we get 7-10fps on PocketPC using WiFi, and 3-4fps on PocketPC with Cell modem.

 

For recording, our disk utilization is about 1/4 using MPEG-4. In other words, if 3 days video would have taken 24mb, it would now take 6Mb.

[FredB 0]

Hi,

Some questions re: Mpeg-4

 

1. How is the quality compared to mjpeg.

2. How is the streaming quality and frame size (2-3k or)?.

3. What driver do you need to acces the camera. Doing alot of daycares

with all these parents want to access the cameras.

 

I have been using the DMVR-16 for local recording and a vpon web server for the streaming part since I feel you almost have to have one compression format locally (mpeg) and one for streaming (H.263) for it to work really well.

 

Any thoughts about that.

 

Thanks,

Fredrik

[DavidR 0]

Fred, most implementations of MPEG-4 allow you to trade off image quality with bandwidth. Depends on the individual application, of course.

 

Using ours as an example, you can have different quality.bandwidth settings for:

-Recording

-Remote access via PC client

-Remote access via PocketPC clients

 

So you could record at a very high quality, and transmit to PocketPC at a lower quality (since the PocketPC device cannot process very high resolutions images very fast anyway).

 

That avoids having to use different protocols for recording and transmitting.