HD MPEG4 vs SD MPEG2

[ReggieRocket]

I'm going to try to give as much detail as I can without being boring. For me, that's a challenge.

I record a lot of TV and when I find something I like, I will edit and burn it off as a DVD if it is not already commercially available. Two series are starting repeat screenings this week which I'd like to get but I don't know which stream to go for. Get ready to hear about some low bitrates. I don't know what it's like in other countries, but in Australia we use PAL and all of our channels are 16:9. All the networks have a main channel in HD and SD, with a few sub-channels all in SD. All of our SD channels (576i) use MPEG2 and the HD (1080i) ones use MPEG4. However, the bitrate for the main channels varies between 3.5Mb/s to 4.5Mb/s. Yes, sometimes it's more or less. But there's a maximum of 23Mb/s for each network.

So my question is which would give me better quality for burning as a regular DVD video: HD MPEG4 or SDMPEG2? I expect the bitrate will be roughly the same on both streams - I once recorded a documentary off both the HD and SD streams at the same time and the SD one had a bitrate of about 0.2Mb/s more and was thus a bigger file! When I burn an SD MPEG2 recording, I don't alter the quality - getting 2 to 2.5 hours on a DVD5. So while the 1080i picture might have more resolution, it is already more compressed and would need "unpacking" for DVD. Should I just stick to native SD MPEG2 or go for the HD MPEG4?

P.S. While I know HD looks better, (1) I'm not that fussed and (2) I want it to be able to be played back, no matter what kind of player I have.

[Cornucopia]

ALL truly compliant "DVD-VIDEO" dvds must use SD MPEG2 compression and be properly authored to be universally playable. You can always add other data file items onto (another folder of) the disc, if you aren't worried about universal compatibility, though.

Since mpeg4 is more efficient than mpeg2, that is how you can use it at those bitrates for hd material , and it probably makes sense to keep both (especially if you want to keep something in HD). An equivalent (quality) mpeg2 compressed version of those HD titles would likely take 1.7x - 4x the size of the mpeg4 versions.


Scott

[ReggieRocket]

Yes but I'm trying to work out if I'd be better off recording the MPEG4 HD stream and converting it to an SD MPEG2 stream as I burn it vs just recording the MPEG2 SD stream in the first place, so that less conversion is needed when burning the DVD Video? I forgot to mention I'm just using Nero to convert the .ts file for DVD burning.

[Bwaak]

Or, you can burn HD to a DVD to produce an AVCHD Disc, playable in BD players (but not in DVD players). Why DVDs? You can burn to BD. What is wrong with files anyway?

[ReggieRocket]

Ah! Nopw that's a good idea, Bwaak. I think I'll do that - didn't realise you could! I'm going from .ts file, so please let me know if there's any additional things I need to do (and could a moderator please move this thread to the appropriate section?). Thank you and, if I remember, I'll pop back when I've got a discful and let you know how it went.

[netmask56]

I tend to record everything at the highest standard, so I would go for the HD channel version rather than the SD channel. As all Australian TV channels are now HD the poor cousins the SD mux generally are at minimum standard especially the commercial stations. The ABC and SBS maintain better standards. I must admit I haven't played a disc for a decade let alone burn one. I keep everything on my NAS in best quality available