Expert help needed please

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I posted yesterday about not being able to burn my mpg1 files as vcd, the burning software i use always rejects them, apart from NTI CD Maker Pro.

So........ I have my avi's ready and i'm happy with the results. (352*240, 25fps, cd audio) If i convert to mpg1 using Panasonic Pal vcd stream standard setting, will the audio go out of synch with the video? And also, i was advised earlier (cheers Doug), that the video data rate might not be high enough to be recognised and hence rejected by cd-r software. I also noticed that if i encoded to 352*240 *29.97fps using Panasonic, the mpg is accepted!?! But the mpg runs slightly to quickly.

So can anyone advise me on the settings for avi to mpg conversion using Panasonic (or MPG Conversion Studio) ie. the data rate - cbr or vbr? Or have i to use other software to correct any/all problems?

And if anyone else had this prbolem and cured it, please let me know how.

Thanks in advance,

Andy. andy@snes.freeserve.co.uk

-- Andy (andy@snes.freeserve.co.uk), May 10, 2000

Answers

I can't give you a specific answer about what is wrong with your VCD streams and why they are not being accepted. Any number of reasons could cause it, but, something is definately not VCD compliant if it is being rejected by a properly set-up burner program.

I can give you some info on the Panasonic encoding. If you use the PAL VCD output template, the stream will be 100% VCD compliant. Will the audio be out of sync? Flip a coin and choose heads or tails. No way to no until you run it through. I have had great results and unusable results. If the source was a VHS taped program, it may get out of sync. Satallite signals captured directly seem to do much better.

There is a way around this. Cut your clips into smaller segments, say about 10 mins each, and run those through Panasonic individually. Then use an MPEG editor and re-join the processed clips. Try to keep your edits on a transition between scenes, ie... when a scene fades to black and fades in to another. This way when you re-join the mpeg clips, any momentary glitches will not be as objectionable.

I have used this method very successfully to encode projects that would always desync when whole.

Also, the reason it is running quick is because you are apperantly processing a PAL captured stream at NTSC rates. Use the PAL template. Oh... also be sure to capture at higher than VCD rate (1150000) before the processing. You can downsample a clip ok but not upsample and get good results.

Hope This Helps, EG Marshall

-- EG Marshall (4me@schoolmail.com), May 10, 2000.


Or another way to fix the sync if it does go out, is to use the virtual dub program. i once explained this. it will convertyour mpeg to an avi, but has a process to keep the video and audio frame rate the same making the sync go in (oh and make sure you use your ORigianl filen ot the one the panasonic made). Well i can explain more if you want just email me. this way i do not have to retype the whole thing again.

-- Doug (mazinz@aol.com), May 11, 2000.

Or another way to fix the sync if it does go out, is to use the virtual dub program. i once explained this. it will convertyour mpeg to an avi, but has a process to keep the video and audio frame rate the same making the sync go in (oh and make sure you use your ORigianl filen ot the one the panasonic made). Well i can explain more if you want just email me. this way i do not have to retype the whole thing again. But this is what i use if the panasonic does make the sync go out and its fixed them all

-- Doug (mazinz@aol.com), May 11, 2000.

One root of your problems is that you are starting with a *.avi file that has hybrid specs; i.e., the frame rate is PAL but the resolution is QCIF NTSC. If you absolutely have to capture at 25fps why couldn't you have started at and chosen 352x288?? White Book rigorously ties one to the other: 352x240 is, and always is for a frame rate of 29.97; 352x288 is, and always is for a frame rate of 25. You might have noticed this with Panasonic when choosing VCD template. You might want to consider this next time to avoid complications converting your *.avis to *.mpg.

-- EMartinez (epmartinez@yahoo.com), May 15, 2000.

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