Whats Better, DivX or SVCD 2 DVD ?

[GarethUK]

whats the best source to start from:

1) DIVX 2 DVD
2) SVCD 2 DVD

I've tried both and get problems with audio sync with the SVCD route. DivX Conversions seem to have a better success rate but most of my sources are SVCD's (2-3 Files) and I've yet to find a way to join and convert to dvd without sync issues.

Any help would be appritiated.

[whatever]

I'd say that svcd is better to start with since they imho are better quality, although none of them are ideal.

Are you resampling the audio to 48khz when you convert from svcd? if not try it and see if your sync problems get better.

[GarethUK]

I've tried two different ways..

I extract the mpeg and encode it using tmpgenc, but then the finished file is out of sync. I even tried extracting the audio through VirtualDub to a WAV file and selecting that for tmpgenc to encode with the mpeg, again same sync problem.

2nd way was through svcd2dvdmpg but still audio sync problem. somehow i need to repair the audio.

[DJRumpy]

I'd say that svcd is better to start with since they imho are better quality, although none of them are ideal.

You must be getting your DivX files in the wrong place. You can place an entire movie in high res video on a single CDR, with DVD quality using MPEG-4. It's leaps and bounds beyond what MPEG-2 can accomplish.

Both DivX and SVCD's typically come from the same source, DVD.

DivX files are typically of higher quality, and higher resolutions, while needing far less bitrate than MPEG-2. SVCD has also had it's horizontal squeezed from it's full width into the MPEG width of 480 pixels. For example, a source file for a 2.35:1 video:

DivX: 640x272

SVCD: 480x272 with the remaining vertical filled with letterboxing

The divx will be of higher quality and usually higher resolution. It uses MPEG-4, where SVCD uses the much older MPEG-2 standard.

That said, converting either type to DVD will usually get you a decent conversion, assuming the source is good quality.

Try this guide for your SVCD's: https://www.videohelp.com/forum/viewtopic.php?t=171216&highlight=

[whatever]

I don't think I'm getting divx from the wrong places, but let's face it divx is not "magical" the only way it can compress the movie more is by using larger blocks.
That means that details will be more blurry in a divx version of a movie, while svcd retains more detail.

Sure svcd will take up more space but typically it will be of better quality.


btw. i have NEVER seen a divx that fits on a cd that is even NEAR dvd quality.

[rilles]

In my experience of converting Mjpeg home movies, I've found that storing them in DVD mpeg2 format had a cleaner picture then storing it in Divx format (Xvid, Divx5.05,3vix - using 100% quality) (tmpenc)

[DJRumpy]

I don't think I'm getting divx from the wrong places, but let's face it divx is not "magical" the only way it can compress the movie more is by using larger blocks.
That means that details will be more blurry in a divx version of a movie, while svcd retains more detail.

Who said anything about magical? Also, what blocks are you referring to? Macroblocks? There are the same size in a DivX file, as they are in an MPEG-2 file. The two technologies are based on the same principal. Temporal and spatial prediction. MPEG-4 simply has the advantage of being a more developed and mature technology than thosed based on the old MPEG-2 standards and methods. MPEG-4 has a larger featureset, better error dectection, and recovery. It also uses has a more advanced scheme for resynchronization. Rather than requiring forced I-frames to keep quality consistant, it can use a marker after X number of bits to force resynch with the last reference frame. It's object based, rather than frame based. It also has smart adaption when it comes to bit errors. I can mask bad data by using references from the adjacent frames, as well as data in the same frame. None of these things are 'magical'. They are simply advances on a technology that's been around for a very long time.
Not to put too fine a point on it, but do you think they've been twidling their thumbs for the last 15 years? Think of what they've done with the combustion engine, or something more relevant, the analog modem. Simply because the new 52,000 baud modems are faster than the old 1200 baud modem, doesn't mean it works worse than the original because it compresses the signal more. The new modems have better error detection and recovery, better compression, and the data is still comming through intact. Same principal here.

The proof is in the pudding. Encode an SVCD at 480x480 @700kbps, and a DivX file at the same 480x480 resolution and 700kbps, and see which looks better.

[flaninacupboard]

Yes but, while the Divx may "look" better, it's different. If someone gave me the option of watching a 352X576 MPEG2 file with an average bitrate of 1.5mbps or a 768X576 Divx file with an average bitrate of 1.5 mbps, i know which i would rather watch.
And i know which i could watch on my TV.

Divx is similar to MP3, yes the achieved quality with super high compression is impressive, but i don't want to watch it (or listen to it) because i know it's not as detailed as the original.

[lordsmurf]

to DJRumpy:
Correct me if I'm wrong, but doesn't the MPEG4 color pallette absolutely suck, as compared to MPEG2 or even MPEG1? I tried my hand at some DivX encodes, only to find that medium-streaming WMV looked better (end product was for downloadable movie clips). I've never seen a good DivX encode. I started from S-VHS footage, editing an AVI in Premiere with After Effects.

[whatever]

Sure, divx gives better results with extremely low bitrates but with higher bitrates, i think not.

Granted a divx maybe has a avg bitrate of 700kbit/s, but it's not uncommon for svcd's to have avg bitrates of like 2000kbit/s.

Which of those will have better quality? I think the svcd will have better quality, divx often introduces artifacts that i have a big problem accepting, i.e. simple almost single colored fields have a tendency to look very blocky with divx.

And the guy in the original post states that he has mostly svcd's that are 2-3 cds each.
i think he'll get better quality with those than any 1cd/movie dvix.

btw, you can hardly compare compression and such used by modems with lossy compression like mpeg.

[flaninacupboard]

Yeah, that's the othe problem with mpeg-4 based codecs, they rely on there being little noise in a signal, and long periods of little to no motion.

It's just not as useful as mpeg-2, I'd never reccomend anyone use it for anything other than a DVD source, and even then it's not perfect. Object based encoding is a good idea, but it's just not advanced or controlled enough to be perfect yet.

If it were used on a movie like Monsters inc you'd see brilliant results at minute bitrates, but that's only assuming you're looking at the bit of the screen you're "meant" to be looking at.

Personally i choose blocks over the slimy mess that Divx can become when starved. Except then it ends up with blocks as well.......

[whatever]

Yeah... maybe that's my problem, looking at the background when i should be looking at the stuff upfront, and when i notice how crappy the background looks i just can't take my eyes off it :P

[DJRumpy]

to DJRumpy:
Correct me if I'm wrong, but doesn't the MPEG4 color pallette absolutely suck, as compared to MPEG2 or even MPEG1? I tried my hand at some DivX encodes, only to find that medium-streaming WMV looked better (end product was for downloadable movie clips). I've never seen a good DivX encode. I started from S-VHS footage, editing an AVI in Premiere with After Effects.

The color pallette is fine. I'm not aware of any color issues. Can you be more specific? WMV uses the same MPEG-4 encoding (MPEG-4) that DivX uses. They are the same technology.

Sure, divx gives better results with extremely low bitrates but with higher bitrates, i think not.

What are you trying to say, that a DivX will get worse as you increase the bitrate? The quality, just like all the other MPEG formats, increases with more bitrate.

Granted a divx maybe has a avg bitrate of 700kbit/s, but it's not uncommon for svcd's to have avg bitrates of like 2000kbit/s.

It's not uncommon, because SVCD requires that bitrate to look good. MPEG-4 doesn't. It it did, we'd be seeing more 2K+ bitrate on encoded MPEG-4 video's.

btw, you can hardly compare compression and such used by modems with lossy compression like mpeg.

I wasn't comparing the two directly, just as I wasn't comparing the combustion engine to mpeg encoding directly. They are two different technologies. The point being made is that technology advances. Things get better.

And the guy in the original post states that he has mostly svcd's that are 2-3 cds each.
i think he'll get better quality with those than any 1cd/movie dvix.

I didn't tell him/her to stick an entire movie on one CD-R. I said that you could fit an entire hi-res divx video onto a CD-R with DVD quality". When I do use MPEG-4, it's always a question of movie length. If the quality will suffer by trying to fit it onto one cd, then i use two. The same methods used for SVCD, CVD, VCD, and even DVD when applicable.

flaninacupboard, you weren't even aware if DivX suported interlaced video. I'm guessing you don't have alot of experience with it. I have experience with both formats, and I'm aware of their capabilities. Again this is all subjective, since we're talking quality here. To my eyes, DivX, or I should say MPEG-4, is a good thing.

Yeah, that's the othe problem with mpeg-4 based codecs, they rely on there being little noise in a signal, and long periods of little to no motion.

Not true. They use the same basic motion detection scheme's that MPEG-2 uses, albeit with newer features. Most of the advancements in MPEG-4 aren't even related to the video encoding process. They are geared more towards error detection and recovery, support for a wider range of bitrates, and a more flexible bitstream.

I don't know why everyone gets so defensive when a new format comes out. It's almost like they've vested something in the old format. I will use the current ones until something better comes along. To each his own 8)

[whatever]

I don't think the quality gets good with divx at high bitrates, i.e. i find a mpeg2 movie at about 6mbit better looking than a divx at the same bitrate.

but hey, that's me... let's not go into a flamewar or anything.

And just for fun, which one do you (djrumpy) find better looking, a 2mbit svcd or a 700kbit divx?

again, I disagree, I have never seen a divx dvdrip, be it 1 cd or 2 with anything even NEAR to dvd quality.

[whatever]

anyways, as to the sync question gareth: have you converted the audio to 48khz?

[DJRumpy]

In truth, I think the 700kbps DivX would look about the same as the 2000+kbps SVCD, assuming they were both encoded properly.

I don't think the quality gets good with divx at high bitrates, i.e. i find a mpeg2 movie at about 6mbit better looking than a divx at the same bitrate.

It does, just as it does for MPEG-2. Remember their both based on the same technology that originated with MPEG-1. The more bitrate applied, the better the image gets, until you get to the point where you have a 1:1 copy of the original that is pretty much indistinguishable from the source. Because MPEG-4 has lower bitrate requirements that MPEG-2, it would reach this point at a lower threshold than MPEG-2. MPEG-2 reaches that point at around 9.8MB/s (10,035 kbps), where DivX reaches that point at around 6000 kbps.

We'll just have to agree to disagree. I do encourage you to experiement on your own though.

[whatever]

I have been experimenting a lot on my own and also looked at a lot of material encoded by others.

And of course i will continue to try out other codecs aswell for now, i'll stick with dvd-r though both for compatibility and quality.

[flaninacupboard]

It didn't support interlaced material last time i really looked at it, it came in around 5.0 didn't it then? In any case the encoder i had didn't support interlace.

You're right, we can all agree to disagree, i've no desire to have an argument about it. Just for me, low bitrate Divx while not looking "bad" is quite soft and blurs details. High bitrate Divx (say 1500 plus) is an improvement, but at this point i would rather use MPEG2, which in my mind, although producing plenty of obvious artifacts, would yield better quality. Or fidelity would perhaps be a better word.

The only point i'll directly dispute is this

until you get to the point where you have a 1:1 copy of the original

That would never happen with MPEG

[DJRumpy]

It could, given enough bitrate. The research papers linked to at the IBM site indicate this happens for MPEG-2 (DVD Resolutions) at around 9.8 MB. You changed the tone of my wording though, by leaving out the end:

get to the point where you have a 1:1 copy of the original that is pretty much indistinguishable from the source

Note I did not say an exact copy, I said indistinguishable, which for most humans, is acceptable

[flaninacupboard]

yeah, fair enough, for all intents and purposes it's the "same" visually, but it would never be identical because of the loss in P and B frames. Although I guess if you excluded these from your GOP you'd get a lot closer to being identical to the source

[GarethUK]

Well thanks for your interesting replies.. So from reading above I'm guessing SVCD is the better source to use.

OK so now thats decided.. What would be better,

1) Joining two files together to create one file to convert.

2) Keeping the files apart and make chapters or something on the dvd to access the 2/3 half ?

[DJRumpy]

{sigh} I give up...

Try the GUIDES section. Specifically SVCD to DVD

[GarethUK]

ok re-read the above and decided DivX will be the better way to go especially since most divx sources are already one file and have less chance of any audio sync probs.

thanks for your detailed replies my brains hurting

[DJRumpy]

Actually, they would both be fine, assuming they were encoded correctly. They should look about the same when completed. Just use the GUIDES section, regardless of which path you take. Look over to the left, in the HOW TO section. The GUIDES page is simple to navigate. If you get lost, or you just have a question, just post in the forum.