Maximum duration of an SVCD

[FakerZ]

What is the maximum length that can be put on a single CD ?

I read that 70mins was some kind of "limit". I've tried to encode 2hours on a CD but I had playback regularity problems (the pic looked great on my PC but my standalone had probs). :confused:

So how much are some of you able to fit on a CD ? Have you had problems to achieve this ? What are the solutions ?

[ppera2]

It depends on compressability of material. But it can't go too high, far less than by Mpeg 4. 70 min is practically max for not demanding material (and wiever). With some crop maybe 10 % more.

[FakerZ]

I must add that I'm not (only) talking about quality. A 2:35 movie will need much less bitrate than a 4:3 one. The 2hours long movie I tried to put on a 700MB CD was in 2:35 and had not much action, so the pic was still great looking.
This one had reading problems very fast, when a 1hour and 20min movie I tried to do later only started freezing at about 70 mins... It looks like the player can't find data fast enough. Strange... because if the movie is more compressed, there should be less data to get from the disc :confused:

[anarco]

This would be a bitrate about 700 kbit (in reduced audio quality) which I wouldn´t call good quality ;)

Though if the material is just a speaker talking for 2 hours while hardly moving the quality may be acceptable.

Maybe a cartoon will work too but the quality will be everything but usable for good entertainment.

There will also be a minimum bitrate limit depending of the source,
the larger the areas of similar color, the easier to compress.
Like a 70´s posterized videoclip or something ;)

[FakerZ]

Hmmm, yes, but again, I'm not talking about quality ! Just about :"why couldn't we store 2hours of video on a svcd ?"

And encoding a 4:3 movie needs 75% more bitrate than a 4:3 one. If you encode a 4:3 at 700 and a 2:35 at 700, you won't obtain the same result !

[FakerZ]

:angry:
Another test, and : this time I got playback problems after one hour with one hour and 7 minutes on a CD ?
What's my problem ? I'm wondering if I did something wrong with multiplexing... Are BBmpeg's SVCD default settings good ?
The fact that it happens only at the end of a CD showw that it has something to do with the data rate...

[Pko]

Originally posted by FakerZ
Hmmm, yes, but again, I'm not talking about quality ! Just about :"why couldn't we store 2hours of video on a svcd ?"

And encoding a 4:3 movie needs 75% more bitrate than a 4:3 one. If you encode a 4:3 at 700 and a 2:35 at 700, you won't obtain the same result !


You can! do it if you want!. In fact, there is people doing this kind of things (see that vcdspain "we-invented-not-following-specs-vcd" silly CVCD, for example). Simply it does not give good quality results for many people... But for many others is OK, and not needing to change the disk at half movie is a nice feature.

Perhaps you want to put 3h in a 74 min CD with 224 audio bitrate... easy! select 472 bitrate in TMPGEnc. You can also select "very fast" in "motion search precision", since there are people that says that that gives "decent quality" for them.

You can then think of a cool name for your "new" format that perhaps many DVD players will play, make a web page about it and rant at your leisure ;-)

Well, irony aside, of course you can store 2 hours of video, simply many people (like me) do not find it at all usefull.

[Mozart]

@ fakerz

It may have something to do with the software burner also. Could you try another software with lower speed of burning?

BTW: I know that some few movies with 2.15:1 aspect ratio can be fitted into 1CD of 80 minutes, with a quality good enough for anyone. However, this is done with a lot of knowledge about the encoding process. It seems that only non-americans know how to do this properly, and I don´t know why this happens;)

[FakerZ]

PKO :

I wasn't talking about quality but I want to make quality SVCDs and nothing else. But how can you really know something without pushing it to its limit ?

I took this 2hours long movie as a test, to see how to fight with CD capacity problems. Now I'm just fighting against problems I have with 65mins SVCDs... :D

[FakerZ]

Mozart :

I tried to burn slower but it didn't solve the problem. Maybe my mux rate is too low ??? I'll try this way. I couldn't find a good reference about muxing so I think I'll have to test. I think I'll burn a lot of CDs before finding the answer...

[Mozart]

type 0 (zero) in the mux rate box in bbmpeg. This will force bbmpeg to choose the best muxrate automaticaly.

as I said before, it can be also a problem with the software burner. I know that, because I do have almost the same issue with fireburner. Using cdrdao, under vcdeasy control, everything works ok. Then, my advice is: try also with another software.

[Pko]

Well, the longer encode I've done was 61 min in a 74' CD-R (the player I had then did not play 80s well), and with 2 audio streams (128+96), and the quality was acceptable (ws movie, really good quality source, very clean, very slow movements... ideal material). I did not do anything special to author it, simply burn with Nero at 4X. It plays OK in 3 different players.

I do not think you should find any problemas if everything is encoded/authored OK with even 90min in 1 CD; going beyond that is ludicrous IMO...Put a minimum bitrate of 300 in your encode, some players have trouble with that (but the culprit IMO is the player, not the encode)

[FakerZ]

Mozart : Thanks for this crucial advice !!
I'm always using CDRwin, I'll try something else...

[FakerZ]

Pko : Thanks too.
I'm trying not to go under 500 already, and I think I'll try not to go over 60 mins on a CD from now on.

[No Rice]

@Mozart
Thats because most Americans are lazy and just want somebody to tell them how to do something without having to invest their own time into figuring it out. I myself fall into that category sometimes when I have absolutely no clue as to what I am doing. Something like burning SVCD's :)