5.1 Surround on DigiBeta? at DVinfo.net

Chris Hocking · November 24th, 2007, 06:59 PM

Hi People!

I am looking into submitting a film into a film festival and the delivery requirement is DigiBeta.

I was just wondering if there's any way to put 5.1 Surround onto DigiBeta?

Is "Dolby E" a possibility?

Obviously I'll ask the festival what the best method is before I submit, but I just wanted a bit of background info before I start firing questions...

Thanks!

Chris!

Douglas Turner · July 9th, 2008, 07:55 PM

Hi Chris,

Was just doing some searches for surround on digibeta and found your post (with no replies!).

Having completed our film in 1080p, I'm really not wanting the festival to show my film in SD off Digibeta... but that's what they've asked for.

Would prefer to show off BluRay, failing that - straight from the Sony Z1 camera off an 85 minute HDV tape, thru component cables. Surely this would be better than off old school Digibeta?

Did you manage to find any info about surround sound on Digibeta?

Has your film been shown - you happy with the quality?

Cheers, Doug.

Chris Hocking · July 9th, 2008, 08:34 PM

Hi Doug,

I completely understand where you're coming from! I mean, after you go to so much effort in post production to achieve the best visuals and sound possible, it really sucks when it finally comes to showing your masterpiece to an audience, and it's projected poorly with poor sound quality.

You can get surround tracks onto a DigiBeta tape - but you have to use a Dolby E encoder. Dolby E is an audio encoding and decoding technology that allows up to 8 channels of audio to be compressed into a digital stream that can be stored on a standard stereo pair of audio tracks. You'll need to get this encoding done at an appropriate post production house - this is not something you can do on your home PC or Mac. The method that was recommended to me was to get your six individual surround tracks as well as your stereo master put onto a DA88 tape. Then this DA88 tape can be put through the Dolby E encoder and re-striped onto the DigiBeta tape.

However! This is the easy part. The problem is, most festivals and theatres don't support Dolby E! Even ACMI (Australian Centre for Moving Image) in Melbourne doesn't have the ability to decode Dolby E for a DigiBeta deck.

Unfortunately, for a lot of theatres/festivals in Australia at least, the only way to play surround off DigiBeta is to encode the audio using Dolby Pro Logic II. This is an improved implementation of Dolby Pro Logic. DPL II processes any high quality stereo signal source into "5.1" - five separate full frequency channels (left, centre, right, left surround and right surround) plus one low-frequency-effects (deep bass) channel. It's not perfect - but I tend to think that it's a lot better than standard stereo.

Everything really depends on WHERE you are showing your film. Each theatre and festival will have their own unique setup - there doesn't seem to be any real standard. Bringing your Z1P along and playing your film off that is good in theory - but you'll still run into the surround sound issues. The only option you'd have is to record a Dolby Pro Logic II mix onto the tape - but because you'd be recording in HDV, you'll have HEAVILY compressed audio. I don't think this is the best option.

If the festival will let you (which I doubt), bringing along a Mac and playing it directly off that is probably a good option - especially if their amp supports discrete surround inputs.

Obviously BluRay (or even HD DVD) would make life just so much easier!

Chris Jones has discussed these issues on his blog a few times as he's going through the same stages as you. Well worth a look: http://livingspirit.typepad.com/

Hopefully RED RAY solves all this problems...

Chris!

Douglas Turner · July 9th, 2008, 10:57 PM

I forgot about the compressed sound... otherwise HDV exhibition would've beaten DigiBeta.

Already suggested to the festival folks that I could supply the BluRay player etc, but they poo-poo'd it, mentioning pauses at layer changes as a show-stopper.

May see if I can fit the film on a 25G BluRay (and hence, I believe not have layer change that a 50G BluRay would have)...

I'd understand if it was a short film fest, and they were showing 20 films in a day, forcing everyone to use the same format would be wise. But with only 2 films being shown on the evening - and one most likely from film - I can't see it being an issue. May have to circumvent the red tape and talk directly to the projectionist - as I'm sure they'd be keen to get the best visuals possible and play with some new kit.

We currently only have a stereo mix, so for this first screening surround's not an issue yet.

Cheers, Doug.

Chris Hocking · July 9th, 2008, 11:12 PM

If you only have a stereo mix, then that cuts out a lot of problems, as every format supports stereo.

Have you seen your film projected via a Digital Betacam deck? As it's a DCT-compressed component video signal at 10-bit YUV 4:2:2 sampling, it's not actually that bad in terms of image quality. Sure it hasn't got the resolution of HD, but it's still quite a nice image for projection. The audio is quite good as well being uncompressed 48 kHz / 20 bit PCM-encoded.

To be honest, I do understand why they hate the idea of using BluRay. Whenever I do live events, I'd much rather be handed a tape on SP, then to be given a DVD!

Will the festival support HDCAM? That would solve all your issues.

Jimmy Tuffrey · July 10th, 2008, 03:54 AM

What resolution does their projector put out? That might be one reason for them wanting SD and then the digibeta makes sense except for the soundtrack. Do they have a surround capable theater? That's the other question I'd ask them.

November 24th, 2007, 06:59 PM	#1
Chris Hocking Major Player Join Date: Dec 2005 Location: Melbourne, Australia Posts: 595	5.1 Surround on DigiBeta? Hi People! I am looking into submitting a film into a film festival and the delivery requirement is DigiBeta. I was just wondering if there's any way to put 5.1 Surround onto DigiBeta? Is "Dolby E" a possibility? Obviously I'll ask the festival what the best method is before I submit, but I just wanted a bit of background info before I start firing questions... Thanks! Chris!

July 9th, 2008, 07:55 PM	#2
Douglas Turner Regular Crew Join Date: Aug 2005 Location: Sydney, Australia Posts: 132	Hi Chris, Was just doing some searches for surround on digibeta and found your post (with no replies!). Having completed our film in 1080p, I'm really not wanting the festival to show my film in SD off Digibeta... but that's what they've asked for. Would prefer to show off BluRay, failing that - straight from the Sony Z1 camera off an 85 minute HDV tape, thru component cables. Surely this would be better than off old school Digibeta? Did you manage to find any info about surround sound on Digibeta? Has your film been shown - you happy with the quality? Cheers, Doug. __________________ Doug Turner http://therunsmovie.com

July 9th, 2008, 10:57 PM	#4
Douglas Turner Regular Crew Join Date: Aug 2005 Location: Sydney, Australia Posts: 132	I forgot about the compressed sound... otherwise HDV exhibition would've beaten DigiBeta. Already suggested to the festival folks that I could supply the BluRay player etc, but they poo-poo'd it, mentioning pauses at layer changes as a show-stopper. May see if I can fit the film on a 25G BluRay (and hence, I believe not have layer change that a 50G BluRay would have)... I'd understand if it was a short film fest, and they were showing 20 films in a day, forcing everyone to use the same format would be wise. But with only 2 films being shown on the evening - and one most likely from film - I can't see it being an issue. May have to circumvent the red tape and talk directly to the projectionist - as I'm sure they'd be keen to get the best visuals possible and play with some new kit. We currently only have a stereo mix, so for this first screening surround's not an issue yet. Cheers, Doug. __________________ Doug Turner http://therunsmovie.com

July 9th, 2008, 08:34 PM	#3
Chris Hocking Major Player Join Date: Dec 2005 Location: Melbourne, Australia Posts: 595	Hi Doug, I completely understand where you're coming from! I mean, after you go to so much effort in post production to achieve the best visuals and sound possible, it really sucks when it finally comes to showing your masterpiece to an audience, and it's projected poorly with poor sound quality. You can get surround tracks onto a DigiBeta tape - but you have to use a Dolby E encoder. Dolby E is an audio encoding and decoding technology that allows up to 8 channels of audio to be compressed into a digital stream that can be stored on a standard stereo pair of audio tracks. You'll need to get this encoding done at an appropriate post production house - this is not something you can do on your home PC or Mac. The method that was recommended to me was to get your six individual surround tracks as well as your stereo master put onto a DA88 tape. Then this DA88 tape can be put through the Dolby E encoder and re-striped onto the DigiBeta tape. However! This is the easy part. The problem is, most festivals and theatres don't support Dolby E! Even ACMI (Australian Centre for Moving Image) in Melbourne doesn't have the ability to decode Dolby E for a DigiBeta deck. Unfortunately, for a lot of theatres/festivals in Australia at least, the only way to play surround off DigiBeta is to encode the audio using Dolby Pro Logic II. This is an improved implementation of Dolby Pro Logic. DPL II processes any high quality stereo signal source into "5.1" - five separate full frequency channels (left, centre, right, left surround and right surround) plus one low-frequency-effects (deep bass) channel. It's not perfect - but I tend to think that it's a lot better than standard stereo. Everything really depends on WHERE you are showing your film. Each theatre and festival will have their own unique setup - there doesn't seem to be any real standard. Bringing your Z1P along and playing your film off that is good in theory - but you'll still run into the surround sound issues. The only option you'd have is to record a Dolby Pro Logic II mix onto the tape - but because you'd be recording in HDV, you'll have HEAVILY compressed audio. I don't think this is the best option. If the festival will let you (which I doubt), bringing along a Mac and playing it directly off that is probably a good option - especially if their amp supports discrete surround inputs. Obviously BluRay (or even HD DVD) would make life just so much easier! Chris Jones has discussed these issues on his blog a few times as he's going through the same stages as you. Well worth a look: http://livingspirit.typepad.com/ Hopefully RED RAY solves all this problems... Chris!

July 9th, 2008, 11:12 PM	#5
Chris Hocking Major Player Join Date: Dec 2005 Location: Melbourne, Australia Posts: 595	If you only have a stereo mix, then that cuts out a lot of problems, as every format supports stereo. Have you seen your film projected via a Digital Betacam deck? As it's a DCT-compressed component video signal at 10-bit YUV 4:2:2 sampling, it's not actually that bad in terms of image quality. Sure it hasn't got the resolution of HD, but it's still quite a nice image for projection. The audio is quite good as well being uncompressed 48 kHz / 20 bit PCM-encoded. To be honest, I do understand why they hate the idea of using BluRay. Whenever I do live events, I'd much rather be handed a tape on SP, then to be given a DVD! Will the festival support HDCAM? That would solve all your issues.

July 10th, 2008, 03:54 AM	#6
Jimmy Tuffrey Major Player Join Date: Jul 2007 Location: Bristol U.K. Posts: 244	What resolution does their projector put out? That might be one reason for them wanting SD and then the digibeta makes sense except for the soundtrack. Do they have a surround capable theater? That's the other question I'd ask them.