"It's also a chicken-and-egg scenario..... because by the time it reaches your house your local cable or satellite operator has compressed your 1.5Gb/s signal down to between 4Mb/s and 10Mb/s typically, making the quality gains negligible." -It's not a chicken/egg scenario. It's Garbage in/Garbage out. That's why you start with a Higher bandwidth signal to allow the codec more numbers to compress (more info) which will allow for a better, finer final compressed product.
"It will solve one problem, which is image degradation due to multiple passes of compression." -No. The only product I am aware that handles multi-generational video compression compensation is the MOLE product from Snell and Wilcox. http://www.broadcastpapers.com/whitepapers/MPEG-2-CLONING-USING-MOLE-TECHNOLOGY.cfm?objid=32&pid=100&fromCategory=49
"... gets ASI compressed into 270Mb/s (best case scenario, satellite transmission is significantly lower bandwidth, and most networks don't use an entire 270M circuit, they use less). -No. ASI is a Transports stream that clocks at 270Mb/s and you can Multiplex many MPEG2/4 bitstreams inside of it. That's how we serve 2 HD and 3 SD channels over one line to our Transmitter.
" It then arrives at the network hub, where it gets decompressed. If it's live it then goes through several switchers and graphics boxes, then gets re-compressed to ASI and sent either to another hub or to your local affiliate. (If not live, it gets put into a server which re-compresses the video even harder before playout.)" -Yes/No. Source Video from Satellite, Tape, ASI over Fiber is De-muxe'd and De-coded,(now the video is uncompressed) and then re-ingested into that facilities Video Servers and compressed/stored at their "house" standard. (Typically MPEG2@40Mb/s for HD, MPGE2@15Mb/s for SD. ) If it's files based video, it is FTP'd to a Xcoder and transcoded to the house standard and stored on their Video Servers(Omneon, GVG, Harris, etc.)..
"re-compresses it into its final 3-12Mb/s data stream for your receiver to decompress one final time." -Correct.
"This would eliminate several compression steps, and mean a better final image quality because you're not recompressing compression artifacts over and over and over again." -Again, this has been solved. (see Snell) No one adopted it. No one will until it makes business sense.
" (also a best-case scenario, most cable/broadcast/sat providers ramp up the bitrate to the max for live sports and then set it back down shortly thereafter)." -Correct. Talking heads get 3-4Mb/s MPEG2 where as sports/NASCAR (high motion, high color) get 9-12Mb/s, and that's after pre-processing usually.
"But the 100Gb/s makes no sense to me. Are you (crazy) overcompensating for latency? Are you sending 100% redundant data for error correction? " -Agreed. Ethernet was never designed for a Live swtiched signal. It's a game of how much risk you are willing to accept in a packet based world. It is possible, with FEC (Forward Error Correction) that this can be acheived though. See SMPTE-2202 parts1&2 https://secure.connect.pbs.org/pbsdocuments/Solutions/Conferences/Technology/2011/Presentations/Whitcomb_Real-time_Professional_Broadcast_Signals_Over_IP_Networks.pdf
"Plus you'd want at least two circuits anyways in case your primary circuit goes down for some reason." -Absolutely necessary. In fact, typical Primary feeds are done over SAT and backup is done over Fiber on the ground.
Now, with respect to the Article.
Can schemes be developed to make an Ethernet Switch act like an un-compressed Switched Circuit Digital Video Router. Sure. With enough cache, bit-rate, and internal packet routing intelligence, I believe it can be solved. (Via hyper fast FEC, you could solve all packet loss's. ie. I can move 100 times faster then a normal human being, therefore, I will catch that person from falling before they even begin to fall or know they are fall
If you really need 30fps, and that much daily storage; the only way to go is either Tape or CD/DVD.
There are CD/DVD "jukeboxes" out there, but none that I know of that will fit your needs. You need to check out Sony's solution.(my old co)
go here:
http://bpgprod.sel.sony.com/bpcnav/app/99999/4/2 00 00/20113.99999.product.BPC.html
If that doesn't work, go here: http://bpgprod.sel.sony.com/
and look under Products / Data Storage / Automated Solutions,, click on DMS8800- PetaSite(TM) System
"PetaSite(TM) System
$151,200.00 U.S. List
The flagship for Sony's large scale digital archive and enterprise data backup solutions. Scalable and highly flexible in design for a storage applications up to 29.0 Petabytes (compressed) or 11.2 PetaBytes (native)"
If this amount of storage isn't enough, ask about the "T-Junction".
Model#DMS8800J
For every T-junction you use, you almost double the original spec.. i.e. 11.2=22.4=33.6 and so on.
The original unit has one Tape Deck Rack that is all Tape Decks attached to 27 Tape Storage Racks with the menacing robotic arm.
Every other Tape Storage Rack can be a T-Junction for an addtional 27 Racks of Tape Storage.
The T-Junction is basically a drop off point for one Robotic arm system (27 racks) to another robotic arm.
If you are good at Tetris, you could probably come up with the Theoretical max Rack layout!
While I was there, there was talk of additional Tape Deck Racks(DMS8800D) to speed up access.
Call them up and ask for SIC (Systems Integration Center) located here in San Jose,Ca.
They can configure one up for you and give you a quote.
this usually blows, but, I have to answer your Q with a couple.
MPEG1 is best done at 2Mbps.
MPEG2 is best done at 6Mbps.
(these are best bang for the bit #'s)
Why r u looking for 5Mbps?
Software based decoding usually maxes the proc with an MPEG1 @ 2Mbps.
I am unaware of a Soft based MPEG2 decoder.
Try VisualCircuits. They have a card that is a 4 port output(composite Video/Stereo Audio) that will decode MPEG1/2.
Oh yeah, you can load one box with up to four of these buggers.
yeah yeah, it runs on NT the best, but Linux dvrs are coming...so they say.
of course, being able to play back MPEG'd video precludes that fact that you need coded media to begin with.
Are you being provided with the crushed video or or you encoding it yourselves?? With what hardware?
Slashdot Mirror
A couple of comments:
"It's also a chicken-and-egg scenario. .... because by the time it reaches your house your local cable or satellite operator has compressed your 1.5Gb/s signal down to between 4Mb/s and 10Mb/s typically, making the quality gains negligible."
-It's not a chicken/egg scenario. It's Garbage in/Garbage out. That's why you start with a Higher bandwidth signal to allow the codec more numbers to compress (more info) which will allow for a better, finer final compressed product.
"It will solve one problem, which is image degradation due to multiple passes of compression."
-No. The only product I am aware that handles multi-generational video compression compensation is the MOLE product from Snell and Wilcox.
http://www.broadcastpapers.com/whitepapers/MPEG-2-CLONING-USING-MOLE-TECHNOLOGY.cfm?objid=32&pid=100&fromCategory=49
"... gets ASI compressed into 270Mb/s (best case scenario, satellite transmission is significantly lower bandwidth, and most networks don't use an entire 270M circuit, they use less).
-No. ASI is a Transports stream that clocks at 270Mb/s and you can Multiplex many MPEG2/4 bitstreams inside of it. That's how we serve 2 HD and 3 SD channels over one line to our Transmitter.
" It then arrives at the network hub, where it gets decompressed. If it's live it then goes through several switchers and graphics boxes, then gets re-compressed to ASI and sent either to another hub or to your local affiliate. (If not live, it gets put into a server which re-compresses the video even harder before playout.)" ..
-Yes/No. Source Video from Satellite, Tape, ASI over Fiber is De-muxe'd and De-coded,(now the video is uncompressed) and then re-ingested into that facilities Video Servers and compressed/stored at their "house" standard. (Typically MPEG2@40Mb/s for HD, MPGE2@15Mb/s for SD. ) If it's files based video, it is FTP'd to a Xcoder and transcoded to the house standard and stored on their Video Servers(Omneon, GVG, Harris, etc.)
"re-compresses it into its final 3-12Mb/s data stream for your receiver to decompress one final time."
-Correct.
"This would eliminate several compression steps, and mean a better final image quality because you're not recompressing compression artifacts over and over and over again."
-Again, this has been solved. (see Snell) No one adopted it. No one will until it makes business sense.
" (also a best-case scenario, most cable/broadcast/sat providers ramp up the bitrate to the max for live sports and then set it back down shortly thereafter)."
-Correct. Talking heads get 3-4Mb/s MPEG2 where as sports/NASCAR (high motion, high color) get 9-12Mb/s, and that's after pre-processing usually.
"But the 100Gb/s makes no sense to me. Are you (crazy) overcompensating for latency? Are you sending 100% redundant data for error correction? "
-Agreed. Ethernet was never designed for a Live swtiched signal. It's a game of how much risk you are willing to accept in a packet based world. It is possible, with FEC (Forward Error Correction) that this can be acheived though. See SMPTE-2202 parts1&2
https://secure.connect.pbs.org/pbsdocuments/Solutions/Conferences/Technology/2011/Presentations/Whitcomb_Real-time_Professional_Broadcast_Signals_Over_IP_Networks.pdf
"Plus you'd want at least two circuits anyways in case your primary circuit goes down for some reason."
-Absolutely necessary. In fact, typical Primary feeds are done over SAT and backup is done over Fiber on the ground.
Now, with respect to the Article.
Can schemes be developed to make an Ethernet Switch act like an un-compressed Switched Circuit Digital Video Router.
Sure. With enough cache, bit-rate, and internal packet routing intelligence, I believe it can be solved.
(Via hyper fast FEC, you could solve all packet loss's. ie. I can move 100 times faster then a normal human being, therefore, I will catch that person from falling before they even begin to fall or know they are fall
If you really need 30fps, and that much daily storage; the only way to go is either Tape or CD/DVD.
2 00 00/20113.99999.product.BPC.html
There are CD/DVD "jukeboxes" out there, but none that I know of that will fit your needs. You need to check out Sony's solution.(my old co)
go here:
http://bpgprod.sel.sony.com/bpcnav/app/99999/4/
If that doesn't work, go here: http://bpgprod.sel.sony.com/
and look under Products / Data Storage / Automated Solutions,, click on DMS8800- PetaSite(TM) System
"PetaSite(TM) System
$151,200.00 U.S. List
The flagship for Sony's large scale digital archive and enterprise data backup solutions. Scalable and highly flexible in design for a storage applications up to 29.0 Petabytes (compressed) or 11.2 PetaBytes (native)"
If this amount of storage isn't enough, ask about the "T-Junction".
Model#DMS8800J
For every T-junction you use, you almost double the original spec.. i.e. 11.2=22.4=33.6 and so on.
The original unit has one Tape Deck Rack that is all Tape Decks attached to 27 Tape Storage Racks with the menacing robotic arm.
Every other Tape Storage Rack can be a T-Junction for an addtional 27 Racks of Tape Storage.
The T-Junction is basically a drop off point for one Robotic arm system (27 racks) to another robotic arm.
If you are good at Tetris, you could probably come up with the Theoretical max Rack layout!
While I was there, there was talk of additional Tape Deck Racks(DMS8800D) to speed up access.
Call them up and ask for SIC (Systems Integration Center) located here in San Jose,Ca.
They can configure one up for you and give you a quote.
Good Luck!
oh yeah, the name of the board is the 4-REELTIME RGB
this usually blows, but, I have to answer your Q with a couple. MPEG1 is best done at 2Mbps. MPEG2 is best done at 6Mbps. (these are best bang for the bit #'s) Why r u looking for 5Mbps? Software based decoding usually maxes the proc with an MPEG1 @ 2Mbps. I am unaware of a Soft based MPEG2 decoder. Try VisualCircuits. They have a card that is a 4 port output(composite Video/Stereo Audio) that will decode MPEG1/2. Oh yeah, you can load one box with up to four of these buggers. yeah yeah, it runs on NT the best, but Linux dvrs are coming...so they say. of course, being able to play back MPEG'd video precludes that fact that you need coded media to begin with. Are you being provided with the crushed video or or you encoding it yourselves?? With what hardware?