CSPS in MPEG1 Video. What is it & how do I get it?

[Computer Nerd Kev]

For some time I have been attempting to encode MPEG1 video compatible with Philips VCD Toolkit without the aid of the TMPEGEnc encoder.

Currently, the only free software which has been able to encode video which was accepted by Philips VCD Toolkit was MPEG2ENC. Unfortunately this software only accepts YUV4MPEG2 as input, which caused problems explored in my previous thread on the topic.

Looking at the output from all the encoders in Gspot and MediaInfo, accepted and non-accepted video appeared identical. However when I later tried MPEG Properties, I finally discovered a difference.

Under the Video 01 tab, the video encoded with TMPEGEnc and MPEG2ENC showed CSPS as the only entry in the "Flags" box. When I tried video from the encoders which gave incompatible video, I found that they had no entries in the "Flags" box.

After a bit of a search for CSPS on the Interweb, the most useful thing I turned up was a translation of the acronym at the "Abbreviation Dictionary for Engineers", which reveals that the full wording of this term is "Constrained System Parameter Stream".

So my question is this:
What is a CSPS or "Constrained System Parameter Stream" and how may one add such a thing to an existing video with out re-encoding (assuming this is possible)?

[Cornucopia]

CSPS says to the receiving application: "Hey, I've been encoded with Constrained Parameters". This may jumpstart the application to being more receptive, but if the MPEG1 hasn't truly been encoded with Constrained Parameters, then sooner or later the application is going to have a hard time with the clip.

"Constrained Parameters" are a strict subset of the more general encoding possibilities within MPEG1. The documentation that comes with Phillips VCD Toolkit does describe most (if not all) of those parameters. I've got it in my archives somewhere...

BTW, there are a number of encoders that do fine with VCDTlkt: TMPGEnc, Panasonic, CCE, BBMPEG, probably a lot more.

What I want to know is: Why are you still messing around with VCD? I thoroughly enjoyed authoring quite complicated VCDs in the past, but that's just it - it's way in the past. Is this just an exercise for you?

With DVD players, burners, authoring & burning software, and Blanks being available for a pittance, it makes no sense to me to keep trying to work with an antiquated format that is really becoming less supported (by hardware).

Scott

[aedipuss]

henc and quenc also make fine vcd mpeg-1. if you really have to make vcds and are still using xp then try svcd2dvd, it has a setting to output vcd from avi or dvd using all free tools(quenc encoder).

[Computer Nerd Kev]

CSPS says to the receiving application: "Hey, I've been encoded with Constrained Parameters". This may jumpstart the application to being more receptive, but if the MPEG1 hasn't truly been encoded with Constrained Parameters, then sooner or later the application is going to have a hard time with the clip.

Thank's for the explanation, however which parameters are being referred to? Resolution, bitrate, GOP structure...

I should point out that I am hoping now to be able to encode straight from VirtualDub in MPEG1 using the ffMPEG codec and then add CSPS to the header somehow. Is it possible to do this manually?

I'm also trying to use only free (not trial or demo) software to do this.

Why am I doing this? Well to be honest this probably mainly is just an excercise for me, however my excuse to myself in doing it is that I don't actually have a DVD burner (yes, yes I know the prices on them).

@aedipuss
I'd like to use VirtualDub for capture so encoders which accept only .AVS input would only be an option if I have some major problems in doing this.

[Cornucopia]

Ok, I don't know how compliant ffmpeg is for VCD, but what I would do in your situation is this:

1. Get TMPGEnc (v 2.54?) It encodes MPEG1 for FREE, without crippling.
2. Get the last Freeware version of VCDEasy.
3. Edit in Vdub (or however you'd like). Encode to MPEG in TMPGEnc, Author the VCD in VCDEasy and burn (IIRC, there is a CDRDAO feature in VCDEasy). If burning no longer works there, use ImgBurn on the BIN+CUE discimage files.

VCDEasy is 99% compliant, compared to Philips' VCDToolkit, so should work fine on most if not all players.
**Note: VCDEasy doesn't work with Vista/7 or in 64bitOSes.

Scott

[vcd4ever]

CSPS says to the receiving application: "Hey, I've been encoded with Constrained Parameters". This may jumpstart the application to being more receptive, but if the MPEG1 hasn't truly been encoded with Constrained Parameters, then sooner or later the application is going to have a hard time with the clip.

Thank's for the explanation, however which parameters are being referred to? Resolution, bitrate, GOP structure...

A constrained parameter bitstream is defined in the MPEG-1 Standard as following:

* Horizontal frame size less than or equal 768 pixels.
* Vertical frame size less than or equal 576 pixels.
* Picture area less than or equal 396 macroblocks (101376 pixels).
* Frame rate less than or equal 30 frames/sec.
* Motion vectors less than or equal 64.
* Bitrate less than or equal 1.86 Mbits/sec
* VBV buffer size less than or equal to 40 Kbytes/sec. (40 Kbytes/sec for constrained files and 224 Kbytes/sec for non-constrained files.)


Vcd4ever.

[Computer Nerd Kev]

Always helps to have the right piece of paper.

In that case, VCD compatible video would also fit the requirements of CSPS. Now if I can just edit the header to tell VCD Toolkit, I should be in business.

If no software exists to edit this flag, can it be done manually, and if so how?
Is the header in ASCII/ANSI?

@Cornucopia
Thanks but believe it or not, I actually plan for commercial use of this and that rules out TMPGEnc (non-commercial only for free version).

Plus the only reason for using TMPGEnc would be for the CSPS flag which seems silly. ffMPEG can certainly get as close to VCD compatible video as TMPGEnc, at least according to my testing.

As for the other program suggestions, I'm not trying to be difficult, but I really want that extra 1%. I can get somewhat obsessive about such things and it's a bit late to give up now.

[Cornucopia]

...Darn it, lost the post!!!...

Oh well, try again.

CSPS may be a "flag", but it's only a flag that verifies that all those parameters are truly constrained. If they AREN'T already truly constrained, you'd still have problems. So just "adding the flag" in the header does NOT fix the problem. You have to actually encode the correct parameters. Ones that you MIGHT think are correct for whatever VCD template you're using, but may NOT be are those that have to do with the motion Vectors, the packet/sector size, and the VBV. That's why even with a nominal template of 1152kbps CBR, MPEG1 system stream, 352x240 @ 29.97fps MPEG1 video, 224kbps MP2 stereo audio might not still be 100% compliant with VCDToolkit.

Let me also say where I'm coming from:
I did commercial VCD authoring for >6 years (incl. both Replicated and Duplicated discs). TMPEGenc & VCDEasy is "good enough" for commercial work and hardware player compatibility.
Also, IMO, if you are going to be doing commercial/profit work on this, you ought to be paying for the software used (whether it's Opensource or not). I would NOT say ffmpeg could get as close as TMPGEnc, and I've done a LOT of testing. So get the paid version of TMPGenc & Vcdeasy. They aren't that much.
Also, there are other 99%+ compliant apps out there (Cequadrat Videopak, etc), but VCDEasy is STILL available, unlike those other apps. And the grandchild of many of those: Roxio Creator, is LESS compliant than VCDeasy. If you really wanted to be 100% compliant, you could try the Philips "PINK" MPEG encoder/multiplexer, but IMO it's a piece of crap!!

Honestly, for commercial work, unless you're doing true AVCDs (and wanting the Audio track link to work within the VCD menu space and not just as a track advance), you'd be wasting a LOT of time trying to wrestle with VCDToolkit, compared to VCDEasy (& TMPGEnc or others).

Scott

edit: this might clear up a few things about those requirements: http://www.icdia.co.uk/cdprosupport/index.html

[Computer Nerd Kev]

CSPS may be a "flag", but it's only a flag that verifies that all those parameters are truly constrained. If they AREN'T already truly constrained, you'd still have problems.

OK I see what you mean, however currently I know of no property of TMPGEnc encoded MPEG1 video which can not be replicated with ffMPEG. So if I can add the CSPS flag to the video and it doesn't work, I'll know that there is a problematic parameter which isn't shown in any of the video information programs I have tried, and will thus most likely give up on the encoder.
However if it does work without problems, then I'll be in business.

In my opinion it's a chance worth taking if there is a method to add the flag to existing video (seems to me that there should be).

If you really wanted to be 100% compliant, you could try the Philips "PINK" MPEG encoder/multiplexer, but IMO it's a piece of crap!!

Strange, I thought PINK was just a multiplexer. In fact I have a suspicion that the multiplexer included with the VCD Toolkit release available at this website is based on it. If there is any version with encoder functionality and downloadable on the net I'd love to know about it!

this might clear up a few things about those requirements: http://www.icdia.co.uk/cdprosupport/index.html

Yes, I came across that a while ago and it sure has been a great help. I just wish they were still around to sell copies of the White Book standard.

Sorry to labour a point, but their PINK page doesn't say much to indicate that it works as an encoder.

[Computer Nerd Kev]

OK its been a while but I have in fact got somewhere with this business.

I used a Hex editor to play with the flags based on info from a couple of sites and found that changing the 12th number from the start of the file to "a4" triggered the CSPS flag without the "Load Matrix" flag when viewed with MPEG Properties.

Unfortunately as if I were destined not to achieve my goal, when I tried to start Philips VCD Toolkit, my computer went straight to a black screen for half a second and then restarted. Further attempts to start the program gave the same result so I was forced to use another PC.

The program ran fine on that machine so I added the file (muxed with the included VCD Mux program) and to my tremendous joy it didn't bring up the usual error message telling of an incorrect video file! I added the file to a simple VCD layout and told the machine to build the CD image.

Sadly this is where my luck ran out as the program ran into a fatal error in the CD image build process which told of an incorrect MPEG stream in the build log.

This would normally be the start of a long series of attempts based around changing parameters in ffMPEG, however the only other PC of mine which was suitable for the task was an early 90s laptop running Windows 95. Although I can get files to/from this machine easily enough using Compact Flash cards, it took over half an hour for it to get to adding the video file to the CD image when said crash occurred.

Thus I haven't yet found the time to see if it can even make a VCD with TMPGEnc encoded input video, and this could yield the same result. If not, trying to find the solution would take a fair while at the rate of half an hour per test.

Anyhow, I hope to find a solution to the VCD Toolkit restart problem (all i've tried so far is re-installing, not that I can think of much else), and if I get it working I'll post information about my results.

Oh, feel free to offer suggestions for this VCD Toolkit problem if you so desire, its a lot of wasted time if I can't get it to work now!

[Milardo]

Hi,

Just found this thread because I have just started using the philips vcd 2.0 toolkit and it seems quite interesting. It works fine in win xp 32 bit for me. Does anyone know a good mpeg splitter and encoder for vcd 2.0 standard so that I can actually get it to import into the program?

[Cornucopia]

If you've read my paper, I think you know my feelings on the subject...

Scott

[Computer Nerd Kev]

The main guide for dealing with files going into and coming out of VCD Toolkit is here. As is mentioed both here and there, the usual program is for splitting/encoding is TMPGEnc.

In case it helps, the guide section for burning the CD images produced by VCD Toolkit only mentions paid software for the final buring, in looking for a free alturnative to this I was unable to get ImgBurn to burn the images correctly (it seemed to insist on mucking up the tracks), so I use the Open Source program CDRDAO.

I also just got a new(er) laptop to use for VCD Toolkit, so I'll hopefully get back to trying my DIY CSPS flag some more. No, I don't know when to give up.