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  1. First of all, hello!
    This thread is my entrance into your virtual world of indexed communications.

    However fear not, I will avoid any long and boring description of myself and get straight to the point.

    First, a description of what I'm trying to do (bet you thought there was a joke coming there, eigh?).

    Basically, I'm attempting to create a VCD (good guess by the way) using Philips VCD Toolkit. Now I know there are much easier ways to author a VCD than with this old blast from the CD's past, however I want every machine that dares to boast VCD support to have the best chance at playing my disks.

    So far I have been able to make a perfectly functional CD image using the recommended method of demultiplexing and converting my input video source using TMPEGEnc.

    Unfortunately not only is this too easy (for my life at least), but it also forbids me from
    (a) Legally making profit from using the software without paying anyone anything
    (b) Using MPEG 1 or 2 as my input format (from what I've seen anyway)
    Perhaps you would not care much about these factors, but to me they act as a significant incentive to look elsewhere.

    I had a look around the world's widest web and soon settled on ffMPEG as the only other MPEG1 encoder which seemed to support the high level of control required for Philips compatible encoding (feel free to point out others to me though).

    After using another program to demux the video (yes I know ffMPEG can do that too but I couldn't be bothered), I first tried to (rather optimistically) encode using the "-vcd" argument. As one might expect, the end product wasn't quite VCD enough to pass by the watch of the Philips multiplexer so it was back to the documentation with the aim of putting in all the settings listed (although modified for PAL) in the guide (which is here in case you missed it earlier).

    This was fairly simple right up until I came to setting the GOP structure. Now the tutorial simply tells you to insert a bunch of numbers while assuming you have full understanding of what the hell you are in fact setting. Naturally, I had to find out a bit more information on GOP (which I now know to mean Group Of Pictures). In the end, I found that this page, along with others at that site, gave me a fair idea of the concept and I was thus set to wade my way through the list of command line arguments in the documentation looking for what would now be an obvious setting.

    Problem is, I didn't find it.

    What I did find were these commands:

    ‘-b_qfactor factor’

    qp factor between P- and B-frames
    ‘-i_qfactor factor’

    qp factor between P- and I-frames
    ‘-b_qoffset offset’

    qp offset between P- and B-frames
    ‘-i_qoffset offset’

    qp offset between P- and I-frames
    Hmm, helpful.
    Unfortunately, this is the only reference to GOP structure in the documentation (which I can find anyway), and even though I have a fair idea of what the I, P and B are about, the difference between "factor" and "offset" escapes me .

    Of course, ffMPEG does also give you the "-g" option to set the GOP size. However from what I can see, setting this to the number of letters given in TMPEGEnc's GOP display, will still give you an incorrect GOP structure.

    Anyhow, that's my problem and any help would be greatly appreciated. Feel free to either give a long and complex explanation of the digital forces at work under the power of these arguments, a quick example of the command line switches you use yourself, or point out the fact that I have completely misunderstood what is required for a Philips acceptable VCD video and send me off on my humble way.
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  2. Member
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    If I use this ... -target pal-vcd -g 15 -bf 2 -flags2 sgop

    Gspot shows this ... IBBPBBPBBPBBPBB

    Isn't that what is suggested in the TMPEGEnc VCD guide?

    EDIT:

    The TMPEGEnc example was for NTSC so...

    For PAL -g 12 should give IBBPBBPBBPBB

    -target pal-vcd -g 12 -bf 2 -flags2 sgop

    EDIT2:

    I'm just trying for fun how close I can get. TMPEGEnc VCD guide says "Disable detect screen changes."

    -target pal-vcd -g 12 -bf 2 -flags2 sgop -sc_threshold 80000

    Something like this would do. Then all gops except first and last are same size. But as mentioned in next post, there are no options to close gops (afaik).
    Last edited by Chris K; 1st Jul 2011 at 12:45.
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  3. @ Computer Nerd Kev

    using FFMPeg command-line...
    How to close just first GOP?
    How to close just first and last GOP?
    How to close first and last GOP plus some of intermediates or any other possible combination?
    How to close all GOPs?

    if can not, non-compliance really sucks, anyhow i dropped FFMpeg n Mencoder somewhere!!!
    Last edited by Bonie81; 1st Jul 2011 at 16:22.
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  4. DECEASED
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    Originally Posted by Computer Nerd Kev View Post
    I had a look around the world's widest web and soon settled on ffMPEG as the only other MPEG1 encoder which seemed to support the high level of control required for Philips compatible encoding (feel free to point out others to me though).
    You could give a try to bbmpeg, or to mpeg2enc.

    Fortunately many DVD-players support non-compliant VCDs

    That Philips software is a P.I.T.A., I hate it.
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  5. Banned
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    CNK - Your post is unclear as to exactly what you are referring to, but I'm not aware of any restrictions on TEMPGenc if you BUY it rather than use the free one. There are some MPEG-2 based restrictions on the free version due to patents.

    I've never known of a player that supported VCD playback that didn't play back a disc made with VCDEasy, which is much easier to use than the Philips VCD Toolkit (EVERYBODY hates the Philips program). However, VCDEasy does NOT work under Vista or Win 7 so be aware of that.

    I find your apparent idea to make your own VCDs for profit to be dubious but good luck. Do note should you be counting on international sales that you've got a ton of potential issues with North America. Few players sold there support VCD at all and even those that do may have issues playing PAL VCDs as opposed to NTSC VCDs. Note that most BluRay players in the world do NOT support VCD at all. Whatever you do, please do not attempt to use copy protection of any kind on your disc as all that does is just make paying customers unable to even the play the disc at all sometimes and it just pisses people off at you. I want to warn you that no matter what you do to make the disc as compatible as possible, some moron somewhere will have some old piece of crap that won't play it and that will somehow be YOUR fault. Just be prepared for that. Don't use menus at all in your VCD as devices that support the format often have big problems with those. Almost all the commercial VCDs do not have menus for that reason.

    Lastly, our resident VCD expert here goes by the name Cornucopia so hit him up if you have really thorny issues with the format and nobody else has helped you to resolve them.
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  6. Thanks everyone for your help.

    @Chris K
    Thanks for putting the work into giving such an accurate group of command line switches. I'll be trying them out right away.

    @jman98
    What I'm trying to say is that I'm not willing to buy the full version, mainly because it costs money.
    As for my second problem with the software, I tried to encode in MPEG1 format for input into TMPEGEnc and it said that the video (which played well in VLC) was invalid or unsupported. So I assumed that this meant that it didn't like MPEG1 (and I think MPEG2 as well from my other tests), seeing as it works happily with MPEG4.

    As for my comment that I want to make profit from these VCDs, well thanks for the tips but my plan is significantly more local than what you are thinking of (more add in the local paper sort of thing). Basically I'm just planning to offer some simple VHS to VCD or video file conversion service and will of course be informing customers of potential VCD incompatibilities. I'm only worrying about the licencing due to my personal obsession with doing things like this properly.

    To be honest this is really just my personal hobby project and I like the challenge. After all, it would only take a couple of jobs for me to make back the money I might spend on a DVD burner anyway (yes that's the reason I'm going VCD).

    Still, thank's for giving me those tips and I might well now ditch my menu idea.


    Oh, and as for my use of Philips VCD Toolkit, I actually quite like the interface. Yes it takes a bit of time to learn, but once you've spent a good hour ploughing through the manual, it becomes quite simple (for me at least). Of course this is just another example of my obsession, but I also love the idea of having the best compatibility possible from my VCDs.
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  7. Perhaps QuEnc ? read first comment (https://www.videohelp.com/tools/QuEnc) - there is newer version of QuENC 0.75 AFAIR MPEG-1 is nice and this is my favourite MPEG-1 encoder
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  8. Banned
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    If you can't afford a DVD burner, which goes for about $20 US these days, I have rather large doubts about your whole enterprise. Seriously. If you're sweating spending that kind of money, you have no business even attempting this.

    I do remember that portable VCD only players are uniquely weird and it may actually take Philips VCD Toolkit to make a disc that they will play. Various people have looked into the issue with portable VCD only players and nobody ever figured out exactly what it took to make discs play on it, but VCDEasy did not work and only commercial discs would play. However, being in Australia I have to wonder how many people are really going to be interested in VCD. I also have to wonder how many people in Australia have VCD only portable players. Otherwise VCDEasy will work fine.

    Your TMPGenc problem with MPEG-1 input is bizarre. I'd have to have a copy of your input file to figure out what is going on. It could be that TMPGenc is actually not really refusing to encode the video but that you are misinterpreting the error message it gives back. Or it really could be that the input is so bizarre that it simply can't do anything with it, but such is not normal. I've found TMPGenc able to handle just about anything you throw at it except maybe FLV files.
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    Have you tried "-flags +cgop" for closed gops with FFmpeg ?
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  10. Well I am now able to encode with the correct GOP structure, however I now have a new problem.

    For whatever reason, I seem unable to encode with a constant bitrate. I've tried both leaving the "-target pal-vcd" switch to do this for me, and adding the switches "-bufsize 327680 -b 1150000 -minrate 1150000 -maxrate 1150000" as is suggested in the documentation. Yet in both cases the bitrate jumps around between 1490 and 1396 kbit/s.

    All I can think of is that one of the other switches must be forcing VBR but I really have no idea.
    Anyhow what I do know is that the Philips VCD Toolkit multiplexer program announces "invalid sequence layer start" when I try to use it with the output video file, so any help would be much appreciated.

    Otherwise, does anyone know where to download Windows binaries of mpeg2enc?

    As for this business of closed GOPs, is this important for what I'm trying to do? The guide makes no mention of selecting the option of closed GOPs.
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  11. DECEASED
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    Originally Posted by Computer Nerd Kev View Post
    ... does anyone know where to download Windows binaries of mpeg2enc?
    Here:

    http://sourceforge.net/projects/mjpeg/files/mjpegtools/2.0.0/mjpegtools-2.0.0-mingw-bi...r.bz2/download

    As for this business of closed GOPs, is this important for what I'm trying to do? The guide makes no mention of selecting the option of closed GOPs.
    Well, closed GOPs are important for chapter points and a fast/accurate seeking (or at least some players seem to think so). But I don't recall if they are strictly required by the VCD specs, or if the Philips VCD-Author is even pickier than I thought.
    Last edited by El Heggunte; 3rd Jul 2011 at 02:38.
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  12. Thanks.
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  13. Thanks.
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