Minimum MPG1 file size?

[Choppa]

Hi, I would like to know if there is any way at all in which I can burn a 699 MB (733,908,992 bytes) .avi which is a 0.97 GB (1,049,919,488 bytes) .mpg1 (both 1:39:10) to one 80 minute 700 meg CD disc, whether it be compression or optimization.

Thank you.

[mats.hogberg]

Reencode your AVI to mpg1 at a lower bitrate. It will probably look like ****, but...

/Mats

[Baldrick]

Do you just want a mpg file on a CD? Or do you want a VCD?

[Choppa]

Uhh... I thought any mpg is the format for VCD
I would like to be able to view the mpg on my DVD player, so a mpg on a CD, well actually any format that would work on my DVD but it's a pretty basic DVD player that can play MPG. So yes I would like a VCD.

[mats.hogberg]

VCD has a fixed video bitrate of 1150 kbps (even if some claim it's a max value).
Like I said, lower your video bitrate to something like 925 kbps, audio 128 kbps, and author as VCD with VCDEasy.

/Mats

[Choppa]

So it's the default bitrate that is 1150 but you can change them make the computer think it's an offical VCD?

[mats.hogberg]

Well, encoders like TMPGEnc use 1150 kbps video, 224 kbps audio if you select the VCD template, and locks the bitrate selector. However, you can then load the "unlock" template, and change the video/audio bitrates to suit your needs. If your player isn't too picky, it should play nicely. However, like I said, don't expect miracles when it comes to A/V quality.

/Mats

[Choppa]

I see... Thank you for your help Matt and Baldrick.

[jman98]

Choppa - You meant well, but the size of your original AVI file is completely useless to answer your question. How LONG is the file? VCD format allows for one minute per minute of CD-R space. That means you can have 80 minutes of VCD video (and audio) on an 80 minute CD-R. If your original video is more than 80 minutes long, you have 3 choices.
1) You can encode to standard VCD and use an editor to split the output into 2 discs.
2) You can encode the VCD at a lower video bit rate to save space. Quality will suffer and you must still use CBR encoding to try to stay close to VCD specs. I believe that VCD version 2.0 actually allows you to use video bit rates below the normal 1150 Kbps, but you MUST use CBR encoding.
3) You can buy 90 minute CD-Rs, if you can find them, which will allow you to burn up to 90 minutes of VCD video at standard bit rates (1150 for video, 224 for audio). Or you can lower the video bit rate (lowering the audio is possible, but it saves little space over video) and the larger disc size gives you even more space to burn to than on an 80 minute CD-R. Do understand that 90 minute CD-Rs violate CD standards and some burners may not burn them correctly. I've never had any playback problems with these discs, but you need to burn them as slow as possible to avoid errors. Depending on the disc, any burn speed above 8x might be iffy. If your CD burner can't burn any slower than, say, 16x, be sure any 90 minute CD-Rs you get are rated for that speed as the faster you burn these discs, the greater the chance of errors. 4x burning is really ideal for them and I have used 8x in a pinch, but the faster you burn, the riskier it is.

[mats.hogberg]

The duration is given as 1.39.10, which I used in my calculation to arrive at 925/128 kbps V/A bitrate for a 80 min CD-R.
Generally I agree on lowering audio bitrate is useless, but at this video bitrate, it actually can make some difference - 829 vs 925 video bitrate; > 11% higher can make all the difference between "watchable" and "awful".

/Mats

[jman98]

The duration is given as 1.39.10, which I used in my calculation to arrive at 925/128 kbps V/A bitrate for a 80 min CD-R.

Somehow I missed this is the overwhelming flood of too much information in the original post, but indeed it is there. Thanks Mats.

In this case I cannot recommend the 90 minute CD-R method and I would say that you really should simply use a video editor to split this into 2 CDs.

[AlanHK]

I take it you don't have a DVD burner, just CD?

Anyway, commercial VCDs almost all break movies into two or even three disks, each disk 60 or 70 minutes at most. Is it really worth the convenince of putting it on a single disk to reduce the quality below standard VCD?

[Cornucopia]

There are a few other things you could do to help maintain a little of the remaining quality while still lowering the bitrate, but they get a little wacky:
VBR, mono audio, 15fps, letterboxing/cropping, posterizing color, substituting stills for some credits...
(I don't really recommend these, but they're fun to try--just to see that it can be done)

What about just getting a new DVD player that plays AVI/DivX/Xvid?
Or a DVD burner?

They really don't cost that much.

Scott

[mats.hogberg]

VBR, mono audio, 15fps

...would all and each on its own make the mpg non VCD compliant, and likely to suffer from playback problems, if it'd play back at all.
IMO, either lower video bitrate and live with the low(er) quality, or split over 2 CDs to get as good quality as the VCD format allows for.

/Mats

[Cornucopia]

That's why I said I don't recommend those.

However, I HAVE made some test discs which do incorporate each of these features and they do play on a number of players (though likely not the majority).

Example: Low motion drama. Drop every other frame -> 15fps. Double the frames -> back to30fps. But now there are pairs of indentical frames. If higher motion, you would surely notice the stutter, but not so much with low motion. This will encode more efficiently than normal 30fps. No "incompatibility" (because it IS 30fps, just VERY redundant).

That's tangetial though. OP should get a DVD burner/new player (or split to 2 VCDs).

Scott

[EddyH]

Is this the same place I signed up for back in the days when it was VCDHelp?
Argh!
OK, let's start again, without assuming he's got some backwards player that's locked to the standards, or at least is incapable of testing for this....

Choppa... it's perfectly possible your DVD player is only compatible with standard VCDs (or no VCDs at all), as I've experienced with a friend's player, but you've got a good chance of it being slightly more capable and therefore a little less strict about what kind of disc you can use in it (like my own, which was at the time the cheapest no-mark model available...). You may have to create a couple test discs and see how you go. But a 100-minute video on one VCD in watchable quality isn't unknown; I have several in my posession. They look like crap on our newest Wide 32" HD LCD because each pixel is now about a centimetre wide, but they're perfectly fine for viewing on a normal shape 14 - 21" tube.

Grab yourself a few blank CDs (or CDRWs for preference), some short but high quality example video e.g. a downloaded music video, and let's take a condensed stroll through the all-about-VCDs section hidden off somewhere on the left

Option 1 (and first test disc) - Standard VCD
Plonk the video into any half-decent program that can spit out VCDs and let it burn. You can either make the file seperately e.g. with the normal TMPGEnc profile, and drop it into VCDEasy or a recent version of Nero (etc), or put your original file into a slightly older Nero version (in both cases after choosing VCD). These are just the programs I'm familiar with but not so bad choices
(Why the distinction between the versions of Nero? Recent testing after upgrading from v5 to v7 shows Ahead have inexplicably done a number on their VCD encoding, and it's all gone to hell and is not even standards compliant any longer )
Take this CD and put it in the DVD player. See if it plays. If it does, that's at least a small victory and something we can fall back on - encoding at standard rate, over two discs of 50m each. If it doesn't... switch to whichever of CDR or RW you weren't using and re-try. If it still won't work ... give up and invest $19.95 in a DVD burner and a further $4.99 in a pack of 10 DVD+Rs.

Option 2 - Slightly non-standard constant bit-rate VCDs
A few discs this time, variations on a theme. You'll need a 'real' encoder like TMPGEnc or HC this time. Try the following combinations of settings on that same video (remember to rename the files and keep track of which is which!)... tweaking and encoding shouldn't take more than a couple minutes for each on a modern PC:

1150kbit/s video, 224kbit/s stereo audio - IE standard VCD for reference, and to familiarise yourself. Also in TMPGEnc look under the "System" tab and ensure it says MPEG-1 (VideoCD).
1150k video, 224k audio - change system to MPEG-1 (VCD, nonstandard)
1054k video, 224k audio (nonstandard again)
1150k video, 128k audio ---- reducing the overall bitrate by a small, similar amount in both cases (enough to fit about 86 minutes of material on an 80 minute CD without over-burning).
1054k video, 128k audio ---- further... (93 minutes; similar to setting the audio bandwidth to minimum. I've successfully fit a season of 24 onto 12 VCDs using roughly these settings and it was OK)
838k video, 96k audio - fairly hardcore reduction... 117 mins
623k video, 64k mono audio - extreme reduction, basically doubled running time.
400k video, 48k mono audio - pushing even further
200k video, 32k mono audio - just to see if it'll accept the abuse.
1150k video, 320k audio - now slight increases
1246k video, 224k audio - equal to 74m on an 80m disc
1246k video, 320k audio - 70m
1805k video, 320k audio - significant increase (51m)
2364k video, 384k audio - doubled data rate, about max it's safe to assume for SVCD compatible DVD players
3000k video, 384k audio - more testing of extreme situations...
3640k video, 384k audio (4000k total) - if this works, then it's silly, because that's almost matching the average rate of a typical DVD...

and also
1246k video, 128k audio - swapping audio fidelity for improved video (a profile actually supplied with tmpgenc)
1054k video, 320k audio - and vice versa.
If you're bored, you can see what happens if you try encoding these with Standard VideoCD system turned on, but it's only worthwhile for those that add up to 1374k or more; the encoder will pad to this figure if the internal rates are lower, and you'll literally be wasting disc space!

Now you've ploughed through that monotonous mountain of rates and got the files together, dump them all in your preferred burner (in a sensible order if you can) in VCD mode, ignore any non-compliance messages, wait a couple minutes for it to burn, and put in the DVD player again.

Most likely to work - the regular 1150k video / 224k audio rate, whether standard or nonstandard.
Next most likely - video/audio exchanging for a maintained 1374k total.
Should be ok but not guaranteed - lower overall rates, particularly if really low, 1/2 speed and less but can be tetchy. May exhibit jumping, skipping, loss of audio/visual synchronisation, odd artefacts etc. My own player is good for this but eventually balks at about 300k overall stream rate (you'll need approx 1100k for that particular video).
Less likely - higher overall rates. If it can only spin the disc at 1x speed, you'll know about it pretty quick, as even the 1246/224 mode will cause it to start skipping or even locking up within seconds. There's a good chance if it does any higher speeds then it'll be ok all the way up to 2x, and some even go higher than this, though this is a waste at standard VCD resolution as it's effectively the same compression level as max-rate DVD by that point.

Hopefully you can at least use a fixed, slightly lower encoding rate to squeeze a bit more on the disc without the player complaining. The best way of adding a few minutes capacity is to reduce the audio bit rate (particularly using a more efficient external encoder), down to 192, 160, 128 or even 112kbit before you think about reducing the video setting, and then you don't need to drop it as far either. MP2 can actually sound pretty good with a decent encoder at these rates; not *so* much "worse" than MP3, merely "different". EG for this 100-minute movie you could have 128k sound, 972k video (or 160/940) and - assuming it's letterboxed - not suffer *too* badly in terms of overcompression.
(I know it's 99:10 not 100:00, but you should always allow a little extra for overheads)

Wow, this is turning out long winded. Don't worry. Once you get your head around it, it's fairly simple and makes sense. There's just a few numbers and repeat tests to deal with first seeing as we can't psychically mind-meld with the player over the web Also it gets you a bit of encoding and burning practice without there being anything important (or truly long winded) at stake.

Now the fun stuff.


Option 3 - VBR
(with 3a - low rate/narrow range, 3b - low rate/deep range, 3c - high rate/wide range)
One of the greatest weapons in the fight to get a full, watchable movie on VCD is the ability to use variable bitrate. If you've found in the previous tests that it won't accept anything other than standard rate, don't bother reading further.

History behind the thing (skip if you like):
The idea behind VBR is that instead of the compression level changing to keep the bitrate the same with material of differing complexities, the compression level stays largely the same whilst the bitrate changes. As video tends to be short bursts of complex material with proportionally more "easy" stuff, this saves data that would otherwise be wasted making the quiet spots look SUPER fine, and spends it on stopping the action scenes from being completely trashed, without (ideally..) any real change to the average data rate. It comes in two main flavours, CQ (1-pass) and 2-pass (adaptive).
1-pass/CQ can give some pretty good results if you choose the right settings, and I used it a lot on an older, slower PC as it was faster even than CBR, but it's hard to predict the output size (certainly to within 50mb), and you can spend more time than you save tweaking the setup if it refuses to play ball or misreads the complexity of a bunch of scenes. Also its aim of keeping the compression absolutely the same (within set bitrate limits) isn't actually so suitable - because of the relative speeds at which things happen, your eye will 'notice' more artefacts in quiet scenes than fast ones, so this rigidity can go counter to CBR and make the slow stuff look crappy and the action super-duper... in freeze-frame anyway, as you don't appreciate the difference when it's moving. Ahem. I digress.
2-pass is therefore the king in most encoding situations (unless you manage to get a multi-pass encoder) - it does one dry run to analyse the material, spoof-encoding it at the desired average rate, noting what the compression rate required to do this is in each scene, and taking motion prediction hints. These are used along with various compensation curves (e.g. to soften CQ's over-zealous rate variation) and other equations to predict the rough average compression level needed to hit the target file-size, and so dynamically alter the bitrate on the real encoding to suit.

The method:
You work out what your average bitrate would be if you were using CBR (minus audio) and plug this in as the desired figure, along with the allowed minimum and maximum rates of your player, and possibly a couple other options depending on the encoder. Then set it going and wait for twice as long as you would for a regular CBR encode and pick up the results as before.

The figures depend on your player, the media size and the source length, basically (as well as the audio), which is where this section branches... If you found in part 2 your player will only accept material with a slight rate reduction, say down to about half, then go for option 3a. If it lets you go really low then go for 3b; if you can go higher as well as lower, try 3c. The basic principles are the same, just the numbers change.

In each case, set 960k as the target average rate (to match the film, and for your test file); if it's slightly higher or lower than that in the end, we can then choose an audio rate to match/decide to over-burn if needed.

3a - Min 575kbit/s (half standard), Max 1214kbit/s (assuming we might use upto 160k audio) or 1246kbit/s (128k max audio)
3b - Min 256kbit/s (playing safe, could probably handle 216), Max 1214 or 1246kbit/s (ditto 3a)
3c - Min 256kbit/s (or lower if ok/higher if it's unhappy), Max 2400kbit/s (again playing safe - might be ok right up to 2600)... if it was good at really high CBR you could increase this, but it wouldn't really make any improvement to any but the most insanely complex scenes, which probably look rubbish even in your source AVI.

The encoder can now take your movie and give it a certain amount of bits every second (in fact on a frame by frame basis) suitable to what the material calls for, with a general perceptual quality better - in some cases FAR better - than what its average (or minimum!) rate might suggest, but smaller file size than what the rate used by it's most complex scenes would also predict. The effects are naturally less obvious and pronounced in 3a than 3c, but you'll still end up with some greedy parts getting 1246 instead of 960, thanks to others only getting 575.

If one of the 3's - particularly 3c, with a ~250k minimum and ~2500 maximum - works for you, then you're really in business. The end result might actually look slightly (to a lot) better than just taking the default VCD choice might have. Get the movie, plug it into the encoder with the right settings, and come back in an hour or so to view the result. Check the combined video stream + audio stream sizes (plus ~10mb per hour if you've got seperate files from different programs, for the multiplexing overheads) are under 800mb - NOT 700mb! - mux them together as VCD Non-Standard if necessary, and put it on a CDR! Maybe even add a menu or intro graphic if you're feeling flash, pretend DVD extras, etc. The world is your VCD oyster. Go kick some ass.

Or failing all that, if it only works as standard mode, find a good scene change to cut it at and settle for making it split over two discs. Or just buy a DVD recorder. Nero Vision Express is cheap rubbish, but it works just fine for the purpose you have in mind - taking an AVI file and spitting out a DVD readable in a regular player at decent quality without much hassle.

Best of luck
MP

[jman98]

If someone is considering option 3, they might as well find out what KVCD is and consider going that route. Do note that using VBR video is completely invalid for VCD at any bit rate, although some less fussy DVD players that support VCD may play the discs. My DVD player will play a KVCD I made just as a test and it uses VBR video. If the guy is going to use VBR video, he might also think about just making an SVCD because VBR is valid for that format.

Whatever Choppa does, he shouldn't expect miracles from low resolution, low bit rate video and the bigger his desire to get this on only one disc, the lower the quality and the more he opens himself up to potential playback problems because any such disc is going to deviate quite a bit from normal VCDs.

[tomlee59]

Impressive amount of knowledge displayed in these posts, I must say!

Here's how I'd summarize it:

1) If maximum compatibility with standalone DVD players is important, then you need to convert/author as standard VCD. This will require two discs to accommodate the 99 minutes.

2) If compatibility and quality are less important, but squeezing onto a single disc is the paramount goal, then back off on the bitrates for both audio and video. Using VBR video and reduced bitrate audio, getting 99 minutes of VCD-quality results is not out of reach. I regularly do this, and use 96kb/s or 128kb/s audio. Many, but certainly not all, DVD players will handle these non-standard discs just fine, particularly if they are low-end models made in China.

So, Choppa, you have a couple of choices, depending on what your priorities are.