Virtualdub saves AVI file size too large?

Motleymongoose · #1 01-11-2016, 09:57 AM

I am in the beginning stages of capturing old VHS tape to digital format using Virtualdub. I have been given great advice and support to this point. I am new to Virtualdub. The capture process seems to be very straight forward so far. What I would like to do is take out all of the gaps in the tapes from when the camera sat too long and does not start were it left off. I know that it is possible to open the captured video and cut the unwanted portions out. I know that I can also keep certain clips and save them out separately. Over the weekend I captured a video. It was about 2 and a half hours and the captured video file size was around 60 GB. It was uncompressed using the Huffyuv codec. I clipped some of the gaps out. About 20 minutes of footage. When I saved it, Virtualdub re-encoded (about 2 hours to save) everything and the file size ballooned to 222 GB. What am I doing wrong or missing?

sanlyn · #2 01-11-2016, 10:21 AM

Quote:

Originally Posted by Motleymongoose

Over the weekend I captured a video. It was about 2 and a half hours and the captured video file size was around 60 GB. It was uncompressed using the Huffyuv codec. I clipped some of the gaps out. About 20 minutes of footage. When I saved it, Virtualdub re-encoded (about 2 hours to save) everything and the file size ballooned to 222 GB. What am I doing wrong or missing?

If you used huffyuv during capture, the captue was compressd -- but huffyuv is lossless compression, not lossy encoding, so that was the correct way to capture. 60GB for 2.5 hours for lossless huffyuv sounds about right, which would be about 1/3 the size of a completely uncompressed file.

However, VirtualDub in "full processing mode" saves as uncompressed RGB by default. So the resulting video is not huffyuv compressed and will be be pretty large. Change your "Video" menu setting from "full processing mode" to "direct stream copy" after making your cut and before saving the AVI, in order to get a smaller huffyuv video.

Motleymongoose · #3 01-11-2016, 10:40 AM

Thank you for the quick reply. Will it still "encode" it on the save? If so, I hope it doesn't take the 2+ hours it took to do the uncompressed edit.

sanlyn · #4 01-11-2016, 03:29 PM

If your AVI was loaded into VirtualDub as huffyuv, "direct stream copy" will save the results of your editing as lossless huffyuv. Output would take not much longer than just making a new copy of your video.

Huffyuv is lossless compression, like ZIP or RAR but designed for decoded lossless video. It is not lossy encoding.

lordsmurf · #5 01-15-2016, 03:02 AM

You did it wrong.

Do not re-encode.

Use the "direct stream copy" option. This does not allow filters, but simple cutting out unwanted footage, and re-saving. I know sanlyn mentioned it already, but I just wanted to reiterate it. Yes, you still File>Save, but that strem copy option is not re-encoding, just saving. The output speed is close to your max drive writing speed (60fps+).

Huffyuv is lossless, not uncompressed. It's about 35gb/hour. Uncompressed YUY2 is 75gb/hour.