View Full Version : Satellite broadcast questions of CF masters


Stephen Armour
March 18th, 2009, 09:35 AM
We have CFHD masters of our 25 min productions output as 1920x1080p. We have been approached by someone wanting to dub and broadcast them via satellite to a foreign country.

Question: how should they normally be prepared and output for standard DV type transmission from our CFHD masters?

William Middleton
March 19th, 2009, 10:25 AM
What do you mean by 'DV'--miniDV? DVCam? Digital Video Transmissions?

There are probably several ways to do this--

One solution:
Output your CFHD master clips to HD tape (HDCam or DVCPROHD), then downconvert to Digibeta, DVCam, or DVCPro for Transmission playout. You may need to throw in a standards converter to get it to PAL if it's going to a different country.

Stephen Armour
March 19th, 2009, 11:28 AM
What do you mean by 'DV'--miniDV? DVCam? Digital Video Transmissions?

There are probably several ways to do this--

One solution:
Output your CFHD master clips to HD tape (HDCam or DVCPROHD), then downconvert to Digibeta, DVCam, or DVCPro for Transmission playout. You may need to throw in a standards converter to get it to PAL if it's going to a different country.

Hold on here. Why would we output to tape to downconvert to DVCam (which is just plain ole "DV-type 2"...that is, audio is linked to video) or DVCPro, when I could probably generate them directly from the master AVI's? Same thing for PAL, isn't it?

Seems like a unnecessary workflow involving tape, when we could probably easily batch convert them from TMPGnc or even from Premiere or other several other video progs. via their codecs.

To qualify my questions, what I guess I'm looking for, is the VIDEO STANDARDS normally used for video to be uploaded to satellites:

is it NTSC 29.97, dropframe, interlaced, or PAL, and could they probably still use our progressive output generated as letterboxed, NTSC 720x480? And what about color standards? We use BT. 709 YUV, so does it have to be converted to 601 color standard?

So please explain too, why you included a tape output for conversion in your workflow.

Tnx

William Middleton
March 19th, 2009, 12:06 PM
It all depends on who is receiving it on the other end and what they are capable of receiving. Do they want NTSC or PAL? A digital video satellite transmission is generally an mpeg-2 transport stream. It could be either NTSC or PAL or HD or HD-PAL.

Most satellite encoders are mpeg-2 based encoders. The inputs to these devices are generally SDI or analog composite (hence the need to dump to tape then playback and send to the encoder). Typical encoder brands are Tandberg, Teirnan, Wegner, and SA PowerVu. The Standard for most of these devices are NTSC 29.97 drop-frame video and most can accept PAL.

There are also HD Encoders, but these are still in essence the same thing--devices that send an mpeg-2 transport stream (with higher bitrates for HD) to satellite for downlink to another location--which will need an IRD to recieve the stream with.

Stephen Armour
March 19th, 2009, 03:18 PM
Logically then, I guess we'll just have to wait for their return on what they currently use to transmit directly into that particular country via satellite. They mentioned maybe receiving the material on DVCAM tapes, with separate channels for the voice and music/FX (which we have ready), but I was trying to second guess them and send in some easier format for us.

I was trying to get away from the DVCAM thing, as the only thing we've got left similar to type 2 DV/DVCAM recorders that accept input, are an old Panasonic DV1000 (mini-DV) and an almost-as-old JVC DV500 cam that accepts and does DVCAM input via firewire to mini-DV. If their DVCAM player will accept our mini-DV-tapes-done-as-DVCAM, we're all set.

I haven't checked, but maybe someone can answer the question as to whether Sony V1's (HDV cams) will accept input for recording to DVCAM on mini-DV tapes? I know they can record original DVCAM video that way, but am not sure about input.

From our location, the easiest thing for us would be to send the finished AVIs to them as files on DVDs (whatever format they want), with the associated audio tracks for their dubbing and upload to satellite. Since our productions are under 30 minutes, they should fit easily.

Complicating things is the fact we need the finished material back from them, so we can add the audio and text to our HD master projects (for the dubbing and subtitles) in both BR and DVD. For that, we'll need a better and easier workflow. Internet is out for us, as our location is not good for speed or good internet!

Thanks for any info and suggestions from you or any others posting to this thread. Since these could go out to many different countries, any help is greatly appreciated!