A JM wrote:
So, it's a processor intensive operation and requires some type of
video out allowing for the connection between FE and TV in a HD
format? Can this be done on a diskless system?
Yes. Just need a good CPU (and perhaps video card) to do the work of
decoding.
If the BE does the recording (HD-3000) and the front end does the
displaying is that stream compressed as it travels the network?
Yes. It /has/ to be compressed. Here's why:
Given that:
1 GiB = 1024MiB = 1048576 KiB = 1073741824 bytes
(see http://physics.nist.gov/cuu/Units/binary.html )
1Mb = 1000 Kb = 1000000 bits
Standard definition recordings in MPEG-2 format require about 1.25GiB/hr
(3Mb/sec) including audio up to a max of 4.25GiB/hr (10.08Mb/sec) at the
maximum allowed bitrate for DVD's. MPEG-4 recordings can, in theory,
give the same quality as MPEG-2 with half the bitrate.
Uncompressed standard definition video will take much more space.
Assuming 720x480 pixels interlaced recording using a 16-bit/pixel
uncompressed format (like YUV or YUV2), a one-hour recording wuold take
70GiB/hr (166Mb/sec) and a 24-bit/pix format (like RGB24) would take
about 105GiB/hr (~250Mb/sec) not including audio.
So, even standard definition TV, when uncompressed, would require more
network bandwidth than most people have--it would even be pushing the
limits of gigabit ethernet.
1080i60 video has exactly 6 times the pixels (=6 times the data
requirements) of 720x480i60, meaning that 1080i60 would require
420GiB/hr (996Mb/sec) at 16-bits/pixel or about 630GiB/hr (1500Mb/sec).
720p60 has almost 5.2 times the pixels of 720x480i60, so it requires
basically the same bandwidth as 1080i60.
When compressed with MPEG-2, these 1080i60/720p60 recordings will take
between 4GiB/hr and 10GiB/hr. Assuming an average of about 7GiB/hr,
that's about 16.8Mb/sec, or a max of 10GiB, that's about 24Mb/sec.
I guess what I'm asking is can a wireless connection handle HD or does
it have to be wired?
You'll have to make the call based on your network performance and the
above numbers, but you're likely to get much better results with a wired
connection--especially when using high definition.
Mike
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