2 Xvids Converted to MPEG PAL and burned onto 1 DVD5....HOW ?

[Clear_Mist]

A bit of advice wanted if you would be so kind.

Following this guide http://users.raketnet.nl/bobv/ntsc2pal/ i am converting a couple of xvids to mpeg and hope to put both mpegs onto 1 DVD5.

In their xvid form they are only 1395MB and 695MB in size. After I re-encode them from NTSC to PAL with MainConcept their sizes increases to 4.3GB and 4.07GB respectively.

In order to fit both onto 1 DVD5 i have tried using DVD-Lab to created individual VOB files first, so next i can use DVDShrink on each VOB indvidually, and then finally take both shrunken VOBs back into DVD-Lab to author 1 DVD5 with a simple menu.

However, even putting each VOB through DVDShrink, i can not to shrink them enough to fit 2 on 1 dvd.
The smallest i can get is 3.45GB

Is it normal to get a file size of over 4GB when encoding (xvid to mpeg2) using MainConcept?

Any suggestions of how i can actually do it?

Many thanks.

[Skelsgard]

If u plan to transcode your DVDs from NTSC to PAL, don´t use your backup XviDs. Use your original DVDs instead.

[manono]

It's better that you get the sizes correct the first time, rather than go over and then try and shrink them back down using DVD Shrink. That guide to which you linked showed both how to use a bitrate calculator, and how to enter the bitrate into MainConcept. Since the final filesize is directly related to bitrate, I'd guess that you did something wrong at some point.

[Clear_Mist]

Thank you both for replying.

Manono - You was right, I was doing something wrong when working out the bitrate.
By following that guide to letter, the bitrate was calculated for a DVD5. By changing it to a custom setting of 2200MB resulted in a encoded video stream filesize of 1.73GB.

Below is a sample of the information displayed in MainConcept when the conversion is started.
The yellow messages weren't display before, when the bitrate was calculated for a DVD5. Are they something to worry about?

The Orange Messages are actually displayed in Yellow, i've just changed this for ease of reading.


Frame 2904: Underflow possible!!!, bits_to_use=167600, in_picture=181944
Frame 7605: Underflow possible!!!, bits_to_use=96360, in_picture=156296
Frame 7603: Underflow possible!!!, bits_to_use=19664, in_picture=151816
V022:vbv_delay underflow! (decoding_time=27403008.2, t_EOP=27405385.0, bitcount=605963512.0, frame=7603)[/B]
Frame 7604: Underflow possible!!!, bits_to_use=-52552, in_picture=125992
V022:vbv_delay underflow! (decoding_time=27406608.2, t_EOP=27411083.1, bitcount=606089504.0, frame=7604)
V025:vbv_delay underflow=-885, bitcount=606089739, frame=7608
can't maintain vbv-integrity on frame: 7608
I:local_skipped = 3, base_min=255, enc_comp=158, T= 13770
Frame 7608: Underflow possible!!!, bits_to_use=-98944, in_picture=490896
V022:vbv_delay underflow! (decoding_time=27410208.2, t_EOP=27433284.4, bitcount=606580400.0, frame=7608)
V025:vbv_delay underflow=-19476, bitcount=606580400, frame=7606
can't maintain vbv-integrity on frame: 7606
Frame 7606: Underflow possible!!!, bits_to_use=-510240, in_picture=22888
V022:vbv_delay underflow! (decoding_time=27413808.2, t_EOP=27434319.6, bitcount=606603288.0, frame=7606)
V025:vbv_delay underflow=-16911, bitcount=606603288, frame=7607
can't maintain vbv-integrity on frame: 7607

[manono]

Hehe, yes, they're something to worry about. It means you may have set the max bitrate too high, or the encoder is going over the max you set, and you may not be able to author the movies. So, it's not related to your average bitrate, which you changed to get the sizes down, but to the max bitrate you're allowing the encoder.

Now, I don't use MainConcept, and have no idea if the max bitrate goes over what you set. But be sure that you don't set the max bitrate too high for the audio you use. And if MainConcept is in the habit of exceeding the max you set, then you'll have to allow for that as well.

You won't know for sure, though, until you author.

[Clear_Mist]

Following the guide quoted in my first post, in MainConcept i selected Constant Bitrate in order to enter the bitrate (calculated earlier), but by selecting this, it 'greys' out the option for entering a maximum bitrate.

Manono, i know you said that your not familiar with MainConcept, is there anyone else who could shed some light on how i lower the Maximum Bitrate?

I have authored a dvd through DVD-Lab Pro, the only flags it threw up was that the GOP's were not closed.
MainConcept does have options regarding GOP's but whatever i change, still seems to make DVD-Lab Pro throw up the 'not closed GOP' flag.
Can anyone advise of the setting required here?

The dvd on the whole, played excellent but for a few instances where the video became quite pixelated and jumped a little.

Manono,
But be sure that you don't set the max bitrate too high for the audio you use.

I am very new to all this and so do not really understand all this bitrate business, could you please explain what you mean in quote above. Thank you.

[Nick]

Slightly OT, in that it remains important that you learn and understand the options at your disposal, but there is a freeware suite for encoding multiple AVI's to a single DVD5 called FAVC

It should work fine with the default settings
http://forum.doom9.org/showthread.php?t=106677

[LocalH]

If you're using CBR, then min/avg/max bitrate doesn't apply and the entire video will use a more or less uniform bitrate (although there is some deviation, it is negligible in most cases). In this case, simply take the desired file size in kilobytes, multiply it by 8 to convert it to kilobits, and then divide that by the length of the video in seconds - this will give you the total bitrate for the final video. Then, subtract the bitrate of the audio from that value, and you'll have the bitrate to use for your CBR video.

Example: Let's say that you want the file to end up at 1024MB. This is 1048576KB. Multiply that by 8 and you have 8388608Kb. If your video is one hour long, then that's 3600 seconds, which gives you a total bitrate of approximately 2330Kb/s. If you are using 384Kb/s AC3 audio, then you subtract that to give you a video bitrate of 1946Kb/s. Of course, this is quite low for CBR and will probably (but not always) result in low quality, but this is just an example of how to calculate CBR bitrates.

[manono]

Hi-

As LocalH said, with CBR encoding, there is no max bitrate to set. Use VBR if you want to set a max. If you got all those warnings when using CBR encoding, then I have no idea what that was about.

Can anyone advise of the setting required here?

Open GOPs gives you a slightly better quality video. I know that some authoring apps warn you about it (needlessly, in my opinion), but they'll still allow you to author. It's nothing to worry about. You need closed GOPS only if editing, or you're working with a multiangle DVD.

[Clear_Mist]

Thank all for your replies.

Nick - I have looked at this thread and i am not sure its quite what i want, which is basically being able to create a dvd with a simple menu for the 2 seperate movies.
But i do agree, that i need to learn about bitrates and options, don't suppose you have a link to any guides/tutorials ?


LocalH - Thank you for your explaination and i do understand it. But i think i am right in saying that this is pretty much done for me when i use the following link :
http://www.videohelp.com/calc.htm


Manono - from the top of my head i am sure that the BitRate calculator, for one of the movies calculated a bitrate of 1990. Maybe this was the cause of the errors, because it was this movie that had pixelation and jumping.

[Nick]

Ah, FAVC doesn't do exactly what you want, there's no menu. It just converts a batch of AVI files and authors a DVD.

As for bitrate, I don't have a good guide handy. I'll quickly do the basics:

Bitrate is the amount of data stored per second of video. The more movement there is from one frame to the next in the source file, the more data your encoder needs to store to reproduce this in the output file.

By and large, you store both audio and video in a compressed format on DVD and the DVD specifications have limits on total bitrate - ie audio bitrate + video bitrate. Also, the size of the media you're recording to is a limiting factor - so if you have a disc of size x bits, and a file of y seconds long, you can calculate how many bits per second you can fit on your disc. As you have seen there are some good calculators freely available.

Next up comes CBR and VBR - CBR or Constant Bitrate stores a fixed amount of data per second, so you work out the target bitrate and set it off. The downside is low movement scenes will be stored in better quality than high movement scenes. VBR, on the other hand - Variable Bitrate - analyses the source and allows more data for high-movement scenes and less for low movement scenes. The bitrate averages out at the same, so filesize is the same as if CBR was used but the bitrate is better distributed to maintain similar output quality throughout.

Your encoder in CBR mode will only have the one bitrate setting available as it will not deviate from it (technically it will a little bit not significantly). VBR gives you three options - Max, min, average. The average is determined by the size of output file you want and is the same as the CBR bitrate would be. The maximum and minimum settings determine how far the encoder is allowed to deviate from the average for very high or very low motion scenes.

However, if you're encoding for DVD, DVD specifications put limits on bitrate. So if you set it the maximum too high or your encoder program exceeds that maximum for some reason, you could end up with a file you can't author a DVD from.

Hope this makes sense.
Nick

[Clear_Mist]

Thank you very muck Nick, yes it made a lot of sense.

I was going to ask you, what do i enter for min and max bitrates when selecting vbr but i found this link which calculates it for me : http://dvd-hq.info/Calculator.html

Just a bit more information please. More as a test than anything else, again using MainConcept, I am encoding to xvid files with a combined length of 2:17:08. The audio mp2 files are 48khz/192kbps.
I am using the VBR option with the following settings :
max bitrate 9300, average bitrate 1900, min bitrate 750
The media size is set at 2000MB

MainConcept's information windows is now displaying the following messages (just a small sample) :

P:local_skipped = 1, base_min=119, enc_comp=141, T= 86572
P:local_skipped = 1, base_min=116, enc_comp=120, T= 75605
P:local_skipped = 1, base_min=128, enc_comp=157, T= 95052
P:local_skipped = 1, base_min=116, enc_comp=147, T= 89723
P:local_skipped = 3, base_min=170, enc_comp=10, T= 15058
P:local_skipped = 3, base_min=153, enc_comp=10, T= 15019
P:local_skipped = 2, base_min=134, enc_comp=10, T= 14739
P:local_skipped = 2, base_min=139, enc_comp=30, T= 22750
P:local_skipped = 3, base_min=167, enc_comp=29, T= 23529
P:local_skipped = 1, base_min=131, enc_comp=88, T= 88923
P:local_skipped = 1, base_min=128, enc_comp=56, T= 65062
P:local_skipped = 1, base_min=117, enc_comp=22, T= 21333
P:local_skipped = 1, base_min=121, enc_comp=30, T= 35091
P:local_skipped = 1, base_min=116, enc_comp=92, T= 109270
P:local_skipped = 1, base_min=133, enc_comp=69, T= 56980


No red or yellow message (which i believe is a good thing.)

But can you tell me what these messages actually indicate? or is it just because the media size is set so small?

[manono]

Hi-

I don't know anything about MainConcept, but just couldn't help noticing:
I am encoding to xvid files with a combined length of 2:17:08. The audio mp2 files are 48khz/192kbps.
I am using the VBR option with the following settings :
max bitrate 9300, average bitrate 1900, min bitrate 750
The media size is set at 2000MB
So, you're converting 2 XviDs to DVD. A DVDR holds about 4480 MB or about 4.37 GB of data. But you're making them total about 2000 MB. That doesn't seem to be 2000 MB each, as your average bitrate is ridiculously low. By my calculations, the average bitrate to fill a DVDR should be well north of 4000. You aren't planning on sticking 4 movies into that one DVDR are you?

[Clear_Mist]

No, I was planning on just putting 2 movies + simple menu onto 1 DVDR.

My first movie is 698MB in xvid form.
The second is in 2 parts, 700MB and 695MB.

At the beginning of all this, I had pretty much no idea what i was doing with bitrates, constant or otherwise, so i thought i could just follow my very first link and convert xvid to mpeg and author a dvd.

My first problem was that the mpegs produced, were calculated to individually fit on 1 DVDR.
Then following your first post, i played around with the bitrate calculator and produced 1 mpeg aroung 2000MB, (with MainConcept, which never threw up any flags).
For the second of my movies (of 2 parts), i calculated bitrates by combining the lengths (as described in bitrate calculator guide), to produce 2 mpegs giving me a combined size of 2200MB.
Now I have 2 movies (actually 3 mpegs), which i can fit on 1 DVDR but of course i was giving no thought to quality (lack of knowledge). This said, the actual quality of the dvd burned, was pretty good except for some pixelation and jumping.

The information given to me through this thread has taught me alot about bitrates, quality and authoring dvds.

However, i am still continuing with my first project (2movies+1menu), as i said, as more of test now, to understand MainConcept better.
This is why i was asking for help with messages now being displayed by MainConcept ...(anybody?).

By the way Manono, which mpeg encoder do you prefer?

[manono]

Hi-

OK, so the combined total is 4200 MB. Sounds good, and you'll have plenty of room for the menu. That 2:17:08 is for only one of the movies, and the other one is another 90-120 minutes, and that's how you got an average bitrate of 1900?

I use CCE. I don't know anything about MainConcept, good, bad, or indifferent.

Here's another MainConcept guide, if you like:

http://forum.videohelp.com/viewtopic.php?t=252501

[Clear_Mist]

Manono, thanks for the link, I will be studying it.

Yes, thats how i got the 1900 av bitrate and i do agree its very low but i'm just experimenting at the moment.

CCE - I remember reading a little bit about this a while ago, does it have a front-end or do you have to use it in conjunction with something like DVD-Rebuilder ?

[manono]

Hi-

It's a standalone MPEG-2 encoder. You certainly don't have to use it together with DVD-RB. There's a trial available (which sticks a logo on your videos). Doom9 has written a guide for the inexpensive Basic version:

http://www.doom9.org/mpg/ccebasic27.htm

And here's their website:

http://www.cinemacraft.com/eng/index.html

[Clear_Mist]

Thanks again Manono, i'll have to, have a little play with the trial version i think.