A question for Dr. Mordid

[Gautam]

Here's what I need to do: Edit a film that has been shot on Betacam SP (PAL) and finally output it back to Betacam SP (PAL). Since the film is not meant for broadcast, I'm going to use my RT2000 set-up. Now my question is:

Should I digitise the footage into DV or MPEG2 @ 25MB/sec? In either case, I'll have to bump it back to Beta. Which will result in fewer losses?

Many thanks in advance!

[Dr Mordrid]

As stated in a previous question of the same type, I'd capture and export DV drom the S-Video ports.

Dr. Mordrid

[Gautam]

Thanks for the reply. I was planning to use the S-VHS port for input-output. But why digitise into DV? Why not into MPEG2?

Is DV better than MPEG2 (@25MB/sec)? Are the conversion losses from Analogue-Digital-Analogue lower when the material is digitised into DV as opposed to MPEG2?

[Dr Mordrid]

I'd only use MPEG-2 if you're going to use chromakey effects or author to DVDiT. It's 4:2:2 colorspace will help with the keying. For "normal" RT-2000 editing DV will do fine.

Dr. Mordrid


[This message has been edited by Dr Mordrid (edited 21 April 2001).]

[Gautam]

Thanks Dr. Mordid. Can you tell me WHY you would use DV rather than MPEG2 @ 25 MB/sec? If the answer is too long and technical, perhaps you could direct me to a site that will give me the information and compare the two forms of compression.

[Dr Mordrid]

Assumption: in your posts MB/s = megabytes/sec?

Capitalizing MB usually indicates bytes and not bits. This is not in the official nomenclature, but is a generally used terminology.

MPEG-2 on the RT-2000 isn't 25 megabytes/sec, it's 25 megaBITS/sec.

Now for the uppance: DV is also 25 mbps

DV is also a bit sharper looking in 'normal' video than MPEG-2 on the RT-2000.

Dr. Mordrid



[This message has been edited by Dr Mordrid (edited 23 April 2001).]

[Frank Marshall]

Hi and please forgive me for barging in on this thread but in the light of this preference for RT2000's DV codec, how does the MPEG-2 facility stack up for DVD authoring? Isn't this the main reason MPEG-2 is there? If one's goal is to author DVDs, is there a better alternative to the RT2000?

Thank you.

[This message has been edited by Frank Marshall (edited 23 April 2001).]

[Dr Mordrid]

It's pretty good. Certainly not as good as using an offline encoder on a YUV source, but very good for realtime capture.

Comparing the two as *some* have done is an apples/oranges type thing.

Dr. Mordrid


[This message has been edited by Dr Mordrid (edited 23 April 2001).]