PowerVCR MPEG2 files and authoring - lipsync problem :(

[arminio]

I checked lot of posts about this problem and still have no propper solution

I capture realtime in MPEG2 using PowerVCR and result is very good quality and A/V synced MPEG file which can't be authhored on DVD without A/V lipsync ... the reason is demuxing which produces video and audio file that are out of sync and can't be fixed (it is progressive lipsync)
I tried everythig I can imagine - fixing with DVDMaestro "create synced track", using VirtualDubMPEG2 to produce WAV or even frameserving to TMPEGENc to produce new MPG audio ... no help

Another problem si that PowerVCR records audio in 44,1 which is not DVD compliant - any help about this ?

Is there any way to solve this A/V sync problems in authoring or maybe anybody know some other MPEG2 realtime encoder that can be used with e.g. AVI_IO ? That would be best solution for my needs ...

[kupton]

I was having a similar problem capturing video from my tuner card and I suspect it was because my capture program would only allow me to do compressed audio and was dropping frames. The resulting MPEG2 files looked in sync on my computer but when I authored it to DVD it would slowly lose sync.

My solution was to switch to WinDVD recorder. The program allows me to record the audio as uncompressed PCM. I haven't had any problems since.

I don't know PowerVCR but will it allow you to do PCM audio?

[arminio]

I was having a similar problem capturing video from my tuner card and I suspect it was because my capture program would only allow me to do compressed audio and was dropping frames. The resulting MPEG2 files looked in sync on my computer but when I authored it to DVD it would slowly lose sync.

My solution was to switch to WinDVD recorder. The program allows me to record the audio as uncompressed PCM. I haven't had any problems since.

I don't know PowerVCR but will it allow you to do PCM audio?

AFAIK, no - only possible mode is MPEG layer II
So, only hope is WinDVD recorder - so, I tried WinDVD but I have another problem with it - I can't capture smoothly at all ! I mean, everything is fine in preview windoww until I start recording - then video start to paause a bit and have a lot od dropped frames in preview and in resulting MPG. Only propprer and smooth recording I get with lowest quality settings (lowest resolution) where preview window is off. Obviously preview mess capturing with WinDVD - any way to turn preview window off (PowerDVD do that automatically and free CPU for capturing) ?

[lordsmurf]

This is known error in POWERVCR ... bad sync in this buggy software.

Capture AVI and encode later.

Try MC 1.4.

WinDVR is not really great either, on par with PowerVCR.

Or use MPEG-friendly card (ATI, Hauppauge, etc).

[arminio]

This is known error in POWERVCR ... bad sync in this buggy software.

Capture AVI and encode later.

Try MC 1.4.

WinDVR is not really great either, on par with PowerVCR.

Or use MPEG-friendly card (ATI, Hauppauge, etc).

HW solution is out of question. Capture o AVI I usually use but I have no much HD o with lower qualtiy settings for source longer than 60 min. which gives me rather acceptable resut but with a visible grain.
Capture to DVD compliant MPEG gives me fine result and I am willing to try this if I can get A/V sync during authoring ...

[arminio]

update:

I just tried MainConcept MPEG encoder and its capture tool and I have the same problem as with WinDVD recorder - tons of dropped frames when using DVD profile no matter what I do !

Now, looks like only PowerVCR II do the job well on my PC (but I can't fix A/V sync after demuxing to produce correct files for DVD authoring) ... other MPEG2 capture tools won't capture well at all ... !?!?!?

[mnkyboy]

update:

I just tried MainConcept MPEG encoder and its capture tool and I have the same problem as with WinDVD recorder - tons of dropped frames when using DVD profile no matter what I do !

Now, looks like only PowerVCR II do the job well on my PC (but I can't fix A/V sync after demuxing to produce correct files for DVD authoring) ... other MPEG2 capture tools won't capture well at all ... !?!?!?

Well, im having the same problem as you. VERY aggravating. I know that mpeg is not meant to be edited, but it should be able to be authored correctly.

Im still trying to find out the main reason for this type of audio sync problem (audio drift). Is it dropped frames in the video stream? If so, why cant a program just add blank frames where the frames where dropped? This would keep the video stream in tact as the original, wouldnt it?

PLEASE, someone figure out a way to do this. AVI capture is out of the question. Seems like the only solution ive been reading, but it seems there should be a better way.

[arminio]

>Im still trying to find out the main reason for this type of audio sync
>problem (audio drift). Is it dropped frames in the video stream? If so,
>why cant a program just add blank frames where the frames where
>dropped? This would keep the video stream in tact as the original,
>wouldnt it?

I don't know ... most insane thing is that MPEG that PowerVCR produce is perfect - while after demuxing, there are tons of lipsync

[Coopervid]

There are some tricks that you could try especially if you have a slower computer and want to record realtime MPEG2 for DVD:


In both PowerVCR and / or WinDVR / WinDVD Recorder record with I-frames only in "Advanced" or GOP 1 / Sub-GOP1. This uses less computing power of your PC and reduces lost frames.

Reduce the format to Half DVD 352x480 for NTSC. Bitrate can also be reduced to 4000 -5000 kbit/s. Usually there is not a big difference if you record from TV.

Unfortunately in PowerVCR you still have to convert from 44kHz to 48kHz. The Intervideo programs let you pick the 48kHz.


Best solution: Buy a Hauppauge Win-PVR250 for roughly $120. This card has hardware compression. I have one and am very satisfied. But if you have a non-Intel PC be aware that it might not work and has some compatibility issues.

[lacywest]

WinDVD Recorder is one way ... but ... try InterVideo Windvd Creator 2 ... instead ... audio options include ... ac-3 ... lpcm ... and mpeg audio ... 48khz.

This is the program I use ... with my ADVC 50.

Or if I choose ... I use my ATI AIW 7500 instead ... to capture inside InterVideo Windvd Creator 2.

Very quick and simple.

[arminio]

There are some tricks that you could try especially if you have a slower computer and want to record realtime MPEG2 for DVD:
In both PowerVCR and / or WinDVR / WinDVD Recorder record with I-frames only in "Advanced" or GOP 1 / Sub-GOP1. This uses less computing power of your PC and reduces lost frames.
Reduce the format to Half DVD 352x480 for NTSC. Bitrate can also be reduced to 4000 -5000 kbit/s. Usually there is not a big difference if you record from TV.
Unfortunately in PowerVCR you still have to convert from 44kHz to 48kHz. The Intervideo programs let you pick the 48kHz.

As I said, PowerVCR has no problem with lost frames or anything - captured video is fantasic and in A/V sync without any pixelation or dropped frames even if I capture in full DVD resolutioon and with bitrate of 6000 and more ....
But, ANY setting in WinDVD recordr produce dropped frames except lowest resolution settings that turn of preview - then I have smooth but crappy quality capture. I will try WinDVD with I-frames and preffered resolution but I doubt thi swill help untill preview is not turned off (and overlay control which WinDVD recorder does not allow to turn on/off and I suspect that there is problem)

[r11532]

PowerVCR MPEG2 files and authoring - lipsync problem

I just came across discussion on this topic and noted that I've had exactly the same problems with PowerVCR. On my PC, PowerVCR’s audio shrinks about 1 second for each 15 minutes of video record time as well as experiencing up to an additional -.3 to -.5 second overall delay shift.

The simplest solution is to use WinDVR instead of PowerVCR. WinDVR produces perfectly synced video clips and its output is 100% NTSC DVD compliant. Unfortunately, the quality of the video is so much better with PowerVCR that it is worth the extra effort to correct its audio problems. I’ve found that VirtualDub has all the built in capability needed to correct PowerVCR’s syncing and 48000 Hz. sampling rate issues.

First be sure to configure PowerVCR’s audio to 384 kbps before capturing your video. Once you have your video, perform the following steps. The result will be a sync corrected wav file that can be used in DVD authoring. If necessary, the wav file can be converted to a mp2 and muxed with the m2v part of the original video to produce a DVD compliant mpeg result.

* Load the video in VirtualDub (mpeg2 version)
* Under Video, "Frame rate," select "Change so video and audio durations match" option
* Under Edit, "Delete selection," select and isolate a few seconds near the end of the video that has lip movement. (Review VirtualDub help to learn how to do this if necessary). Play the clip selection under File, "Preview filtered"
* If the lip sync is off, go under Audio, "Interleaving" and change the "Delay audio track by" a correction value (-300 is the number I usually start with)
* If necessary, go back and forth between checking the lip movement clip and tweaking the delay audio track number until there is perfect syncing
* Under Video, "Frame rate," change back to the "No change" option. Also divide the change duration fps number by the no change fps number to get their ratio
* Under Audio, select "Full processing mode," click on "Use advanced filtering," click on "Filters," click on Add then double click, in order, on input, stretch, then output, then click Close. Click on Arrange to organize the three boxes and configure the stretch box value to the fps ratio
* Play the lip movement clip under File, "Preview filtered"
* If the lip sync is off a little, go back to the audio filter stretch box and tweak the ratio number slightly (-.0001 from the number usually works for me)
* If necessary, go back and forth between checking the lip movement clip and tweaking the stretch filter number until there is perfect syncing
* Under Edit, select "Reset frame subset" to exit from the lip movement only clip back to the full video
* Under File, select "Save WAV" and save the synced audio as a temporary wav file
* Under Audio, reset the "Interleaving," "Delay audio track by" back to 0, delete the boxes under Filters and unselect the "Use advance filtering"
* Under Audio, select "WAV Audio" and open the temporary wav file just saved
* Check the video one last time for accurate lip syncing to the audio
* Under Audio, select "Conversion," click on 48000 Hz
* Under File, select "Save WAV" and save as a final sync and sample rate corrected wav file
* The end