TV Capture with EasyCAP and VirtualDub Audio out of sync

[olobay]

Hi,

Here's the setup:

Core2Duo Laptop 1.6GHz
4GB RAM
Vista SP2
Capture Device EasyCAP RCA to USB
VirtualDub 1.9.11

I am capturing TV using the latest Xvid Mpeg4 Codec and Lame MP3 codec but I can not get my capture in sync. Audio is always lagging. I tried doing the direct stream copy video and audio with an audio delay and that fixed my sync issue at the beginning of the file but it drifted again later. I find it hard to believe that there isn't a solution to capturing in sync in VirtualDub. I have gone through the forum and seen a ton of sync issues with VDub but no solutions yet. Can anyone help me out?

Thanks.

[hech54]

Trying to capture to Xvid and MP3 with an EZCrap and a laptop?

[olobay]

Trying to capture to Xvid and MP3 with an EZCrap and a laptop?

I know it sounds stupid but it works. Video and audio quality are good. It's just the sync that's the issue.

[hech54]

I know it sounds stupid but it works

So the audio sync is fine then?

[olobay]

I know it sounds stupid but it works

So the audio sync is fine then?

Obviously not if I am here asking for help but it seems that a lot of people on this forum are having sync issues capturing with VDub. So you think it's because my computer is not powerful enough?

[Bjs]

Pass the audio directly to the laptops input if possible ... do not use any compressor ... easier for vdub to access and this should cure the sync drift issue.

Compressing the video using xvid is a heavy load for that processor ... you should use huffuy ... while this will create files needing a fair amount of space it takes a considerable load off the processor.

[olobay]

Bjs,

Thanks for the reply. Not sure what you mean about passsing the audio through the input. Right now I am using the mic line input for the audio using an RCA to 3.5 mm adaptor because the USB audio is distorted and has static. I am only using the USB to capture the video. I tried the Huffyuv route with PCM audio as well as LAME and MPEG audio but I still get the sync problems. I tried capturing using Debut software with the same Xvid and LAME encoders (the exact setup I used in VDub) and to my surprise it worked and it was in sync all the way through. However the video quality wass not as good as it was with VDub. Don't understand why Debut worked but not VDub. I'd like to find a way to get VDub to capture in sync.

I checked the CPU load when capturing and it only gets up to around 60%.

[jagabo]

There are several audio sync related options in VirtualDub's capture module. Disable audio playback while capturing. Save audio uncompressed. Go to Capture -> Timing... and try all the options there until you find some combination of settings that works.

[olobay]

Thanks jagabo. I figured out what needs to be selected in the Capture--Timing section in order to get it to capture in sync. It's pretty obvious actually. Just select Do not resync between audio and video streams in the Resync Mode section. Also make sure that Correct video timing for fewer frame drops/inserts is not selected. So with the folowing settings I am able to get EasyCAP to record in sync:

Video Compression Xvid using Xvid HD 1080 profile Single Pass Target Quantizer 1.00 for quality
Video noise reduction enabled
Frame rate 29.97
Audio Compression Lame MP3 44.1kHz 192kbps CBR Stereo

I have a question regarding the Video Compression profile for Xvid. Even though I am recording an analog Standard Definition source, I chose Xvid HD 1080 profile because I assumed that would give me the best video quality. Am I right in assuming that or is there something better?

I am running a test of a long capture, maybe in the 3 hour range just to see if everything remains in sync. I am getting just under 1GB per 10mins of captured video. Now that I have the sync issue figured out, maybe someone can recommend the best video compression setting to record a sporting event (a hockey game) and have the best quality video. Even though there is some minor motion blur when the camera pans or when digital graphics slide onto the screen, I am happy with my setting but I would appreciate recommendations for improvement. I will be converting this to DVD once the capture is done.

Thanks for all the help.

[jagabo]

Thanks jagabo. I figured out what needs to be selected in the Capture--Timing section in order to get it to capture in sync. It's pretty obvious actually. Just select Do not resync between audio and video streams in the Resync Mode section. Also make sure that Correct video timing for fewer frame drops/inserts is not selected.

Hopefully, that will help someone in the future.

So with the folowing settings I am able to get EasyCAP to record in sync:

Video Compression Xvid using Xvid HD 1080 profile Single Pass Target Quantizer 1.00 for quality
Video noise reduction enabled
Frame rate 29.97
Audio Compression Lame MP3 44.1kHz 192kbps CBR Stereo

I'm surprised you can get away with all that compression while capturing.

I have a question regarding the Video Compression profile for Xvid. Even though I am recording an analog Standard Definition source, I chose Xvid HD 1080 profile because I assumed that would give me the best video quality. Am I right in assuming that or is there something better?

The profiles don't do much of anything in Target Quantizer mode. Once you get beyond the first few "Simple..." profiles they don't do anything. If you go to the detailed Profiles dialog you'll see what options they change:



Be sure you're using the "Interlaced Encoding" option since what you're capturing is interlaced video. Be aware that many players don't play interlaced Xvid very well.

I am running a test of a long capture, maybe in the 3 hour range just to see if everything remains in sync. I am getting just under 1GB per 10mins of captured video. Now that I have the sync issue figured out, maybe someone can recommend the best video compression setting to record a sporting event (a hockey game) and have the best quality video. Even though there is some minor motion blur when the camera pans or when digital graphics slide onto the screen, I am happy with my setting but I would appreciate recommendations for improvement. I will be converting this to DVD once the capture is done.

Not using the interlaced option might be the cause of the blur. If you see comb artifacts the player isn't deinterlacing for display. Some players perform a simple blend deinterlace which makes the image look like double exposures when there is a lot of motion. The playback issues aren't a problem if you're going to convert to DVD, just make sure the MPEG 2 encoder knows the video is interlaced.

If you're going to reencode for DVD you might as well disable B-VOPs. That will speed up processing a bit and make it less likely you will drop frames. For SD video I like to use shorter GOPs than the default of 300. I usually use 100. Files will make the files a little larger in Target Quantizer mode -- maybe 1 percent. Shorter GOPs make it easier to navigate in an editor later on.