Video fileserver - Need some input

[Eduardo Morras]

At 14:21 09/05/2007, you wrote:
>I'm planning a new fileserver for my post-production facility and need some
>input regarding filesystems and network setup. I've been a FreeBSD fan for
>almost 10 years now and will try to build this server based on the latest
>stable FreeBSD version, allthough most machines here run WinXP.
>
>We have an internal 1 Gigabit network here and in addition to this the video
>fileserver will have two direct NIC connections to two WinXP capture
>stations. I will most likely be using a Raid-0 or a Raid-5 setup with SATA
>drives. The system will have something like 4-8 TB of HDD space.
>
>I'm not so afraid of loosing data, but we need a system that is fast and
>will allow capture from two external Windows XP machines through direct
>Gigabit ethernet. The datarates are 8 bit @ 720 x 576 @ 25fps = 20 MB
>per/sec, or 70 GB per/hr.
>10 bit @ 720 x 576 @ 25fps = 26 MB per/sec, or 93 GB per/hr.

Are you sure? 8 bits per pixel is too low. For RGB i suggest you use a 8 bit per color (R,G and B) or 24 bit per pixel. Or if you work under YUV/YcrCb spaces a 12bit as minimum (YUV12 or 4:2:0 space). Final numbers for PAL RGB are 24 x 720 x 576 x 25 = 29'96 MB/sec (Your 8x720x576x25 are 9'88MB/sec, not 20) and for YUV12 14'98 MB/sec.

You can use a lossless videocodec for capture, huffyuv is the faster/better and you have a "native" Windows VfW version. All current computers can compress with it "on the fly" (my 3-4 years old 2Ghz Athlon shows 70 fps) and can halve the data rate. In the freebsd you can use ffmpeg based apps for decode it (and encode), that's all apps.

If you can work with lossy video codec use x264 on the Windows side, tuned for "on the fly" / "live" compression, if not you will lost frames. Again, ffmpeg can decode it on freebsd. You can get 1 MB/sec or less. Check dirac (don't know if a freebsd port works) and if you want to pay, try VP7, the big brother of macromedia flash codec.

>In addition to this 1-5 machines will have access to the fileserver through
>a shared Gigabit network connection for making DVDs and use the files as
>source for editing. In short: There will be two direct 1Gb network
>connections and one shared 1Gb connection. Will the server hold up?

Depends on how many readers attacks the files. It's more a bus problem than a OS. If video data is compressed the disk will read/write less and you can serve faster.

>Any other recommendations are very welcome.

Don't use RAID-0. If there is any problem everything become lost. 

>Thanks!
>
>Regards,
>Andreas W. Andersen
HTH

N.B. huffyuv, x264 and dirac codecs are opensource. VP7 is On2 Tech.