Webcasting setups/help

[dcbrown]

Ok, still playing with the software got some of it to work by using Adobe FME.

1. Install FME following the links on ustream
2. Use My Shows -> Advanced on ustream, save xml file which describes the show
3. Open FME, use File->open to open just saved xml, this then becomes the default and then close FME

--only have to do the above once--

4. Open CutFour, connect sources select one for output
5. Open FME, select MediaLooks Multigraph Video - I had to open tool and "connect" to the source
6. I tried connecting to MediaLooks Multigraph Audio, but no joy still so am still using line in
7. Hit "Start" in FME... wait for encode to start and connection to ustream to be established
8. Hit "Broadcast", ustream window opens and should find the flash stream already in place.
9. Hit "Start Broadcast"...

Video output seems a bit better than before, but still not great. More pauses and dropouts. I selected 300kbs to start with in FME, I might bump this up. But there are definitely more dropouts on ustream through this method. But at least its working up to the point of partially using CutFour which allows me to preview incoming sources as well as playing back stored .avi files into the stream output.

PS if you see "DEMO" in the right upper quadrant of the ustream test I'm running that's from CutFour - I'm running the 30 day eval copy and thats the watermark indicating I'm running the demo version.

[dcbrown]

The kind folks at Newnex Technology in CA got back to me. Ummm. Dumb user on device error. I forgot to add the gender bender cable to the setup.

"You should use a CAT5 cable that is wired straight through with our Qu-Cat adapter. The activity light will illuminate when the two repeaters are connected to each other and powered."

Adding the adapter into the cabling lets everything work.

Why is this a big deal? IEEE 1394 has ~15' limit. Long firewire cables can work with some DV camera setups - sometimes, maybe - but its out of spec so ymmv. Evidently neither of my two Sonys nor the Canopus a/d have what it takes to work with the really long cables. The result is the PC doesn't see anything connected when long cables are used.

The FireNex repeater gets me up to 260' away from the camera or other DV source which uses 1394 as the transport. This is huge because it allows the webcast station to be set up where convienent rather than snugged up against the arena feed/drop. These aren't cheap, but an engineered solution is always perferred over the adhoc. This also means the video stream stays digital.

The original idea was to use the FireNex repeater to pump the DV info from the Canopus which would be located at the arena feed/drop location. The problem with that strategy is that the audio isn't cleanly separated from the DV source for webcasting. I'm still pondering a reasonable solution for that, but for now I'm looking at going back to using long analog cables to feed the audio/video from the arena drop to a semi-remote PC location... as long as semi-remote is within 50'. Feed the analog into the Canopus and then into the PC.

Eventually I'd like to put together (maybe next year?) a webcast "kit" which has all the unusual pieces - cables, converters, etc - so it could be utilized by other regional committees. Its not reasonable to buy the setup for something like this and have it used only once a year.

[dcbrown]

There is a lot of misunderstanding out there about video formats which effect how people think about archiving and webcasting and video quality.

From a pure video stream bandwidth standpoint:

NTSC 248Mbits/sec
SD DV 25Mbits/sec DV25
HDV 25Mbits/sec
DVDs 8Mbits/sec (up to 10Mbits/sec) MPEG-2
HDTV 25Mbits/sec
Blu Ray 25Mbits/sec (up to 40Mbits/sec) H.264/MPEG-4 AVC

So when people say they would like HD video, they usually are referring to HDTV or the desire to have 25Mbits/sec video rates. This means a typical 3 minute match will be somewhere around 650Mbytes in length.

Often there is the mistake to think that any/all H.264 compressed video as high definition. But some H.264 converters such as Haivision's OSCAR converter only converts analog composite video into a H.264 1.5Mbit/second data stream max. Not even close to the 25MBits/sec "real" HDTV needs. In many cases converters like Canopus's ADVC110 which converts to DV25 will produce better results to work from. Although the real limitation is the NTSC composite video signal you're starting from...

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NTSC analog signal, uncompressed and converted to digital is estimated as generating roughly a 248Mbits/sec data stream. Visible vertical resolution is somewhere around 486 lines best case (no overscan, etc.)

SD DV camcorders (standard definition, digital video) generate and record in DV25 format - 25Mbits/sec video stream. Add in the audio which is not compressed plus overhead and you are looking at 28.8Mbits/sec data stream or 3.6Mbytes/sec. The DV25 format is referenced as a 10:1 compression. This is what is recorded onto miniDV tapes for example. However, if the camcorder records on DVDs the video stream is further compressed using MPEG-2. The standard DVD is usually authored with a 8Mbits/sec variable bit rate data stream. DV25 when captured onto a computer is usually written into type 1 or type 2 AVI files. No further compression is done during such capture. This is the best format to start editing with as most video editors utilize this format as input. Compressed formats are harder to reconstitute - usually you end up uncompressing via the appropriate codec and then later re-compressing into whatever output format you want. Everytime you decompress/compress you are likely to loose more of the video signal. SD DV is 720x480 - equivalent to 480p or 480i, but not exactly the same. This means that a 3 minute match in AVI format takes up 648Mbytes. Reading a full 1 hour miniDV tape to your computer or capturing 1 hour of DV25 video on your computer results in 10GB-12GB of data.

DVDs as noted above use MPEG-2 compression and typically are authored with a 8Mbits/sec video stream. Applying MPEG-2 compression typical results in another 3:1 to 4:1 compression. A standard DVD holds 4.7GB in each layer and holds roughly 1 hour of compressed video. Most DVD burning software will allow you to select a slower 4Mbits/sec to double the amount of video put onto the DVD. However, the best bet is to record in SP - standard play or the 8Mbits/sec rate to capture the best possible video for later use.

HDTV has a 25Mbits/sec data rate (at least that is what I've seen mentioned).

HDV utilizes MPEG-2 to compress higher resolution data. This is utilized by Sony, Canon, JVC, and Samsung. The audio is also compressed via MPEG-1 Layer 2 -- but the audio is sampled at a high 384k/sec rate. The compressed audio is almost but not quite as good as the DV25 standard. But! this means the HDV data stream is 25Mbits/sec -- same as SD DV.

DVCPRO HD is Panasonic's competing HD video format, it has a 100Mbits/sec video data rate.

Blu Ray DVD supports up to a 40Mbits/sec video rate (I've seen 54Mbits/sec but think that is combined video/audio or a pure data rate?). Typically however the output rate is matched to HDTV needs - 25Mbits/sec. Each layer of the Blu Ray format stores 25GBs, or ~5.3 times as much as a SD DVD.

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None of the above video stream data rates are sustainable over a public network - either as an archived file or webcast.

Archiving videos is usually done by taking download bandwidth into account -- how long do you want a download of a 3 minute match to take? The current recommended specification for creating an archived match is to utilize a 1-1.25Mbits/sec rate. This results in a 25-28MByte file for 3 minutes of video. With a high-speed connection, this results in <5 minute downloads. With a good connection and no QoS issues you might even be able to download this video in realtime. Going to storing native DV25/AVI files would need 25x more storage and download time. The data rate for HDTV is similar, so similar size files would be needed for HD 1080i files. Not realistic.

For webcasting, you are limited by uplink bandwidth. I've got a reasonable upload capability at home - 800kbs to 1000kbs typical. For webcasting purposes the guideline is to only used 1/2 to 1/3 of the instantaneously available bandwidth. I've not had any problems webcasting to ustream at 350kbs, a few glitches (pauses) at 400kbs, and an annoying number of glitches/pauses/rebuffering at 500kbs. Note these are video bit rate speed - add at least another 92kbs for the audio stream. You can also reduce frame rate to balance off video rates as well as webcast in 320x240 resolution.

So choosing to use MPEG-2 or MPEG-4 AVC/h.264 is insuffient to specify the visual representation of data. The bits/sec rate is actually more of an indication of video quality. MPEG-4 AVC/h.264 is a newer and arguably better video compression standard - it handles motion better is the normal observation. Just don't confuse the compression standard being used with SD or HD quality... an SD DV25 AVI file will look a lot better than a 320x240 12 fps h.264 1Mbits/sec data stream for example.