Simple Q .... I have been capturing VHS tapes into DV format using WINDV as capture program.
This results in lead in lead out 'garbage' I have been using VD to trim this out and then setting "Direct Stream Coyp" on both Audio & Video .. using save as .avi
Ready for when I want to process ........ is this non destructive ? (I had assumed so) ... I am not transcoding or rescaling anything ...... I ask as it seems to take quite some time for VD to do the save as ... (10min plus for some) at 10.6GB video rate.
Sort of thought with only snipping off start and finish seconds 'save as' would be quick.
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Thread: Capture & Trim with VD
AFAIK VD is very fussy when it comes to stream copying. EVERTHING must be identical and I guess as you can not save in the codec originally used then re-encoding takes place.
You would be better off doing the TRIM as part of an avisynth script.
I looked at Media info on original and the trimmed file .... both are exactly the same so don't think its a codec issue.
If I used an aviscript ... wouldn't that just use VD just the same ? just driving it form a different point ? (or I may be totally wrong)
Looking at clip on VD I can get it to exact frame for cut point, with script how would you do that ... or do you mean find frame numbers first in VD and then enter them into script.
Find frame numbers first in VD, then enter into a script. Remember that the first frame in a video is numbered 0, not 1. Example, if you want to delete frames 0-650, then Trim(651,0) will delete frames 0 to 650 and keep frames 651 to the end. The new start frame will then be numbered 0.
If you want to remove 650 start frames and the last 1050 frames of a video with 200,000 frames (the last frame number in the video will be 199,999), use Trim(651,198949). Use "fast recompress" in VDub to save the results.
Easier: open the video in VirtualDub, cut your frames from the start, then cut off the end if desired. Save with "direct stream copy" or "fast recompress".Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
Avisynth will require recompressing.
I keep forgetting it's DV.Our inventions are wont to be pretty toys, which distract our attention from serious things. They are but improved means to an unimproved end. -- Henry David Thoreau
AviSynth would require re-encoding.
As long as you use Direct Stream Copy mode (audio and video) VirtualDub is lossless for DV to DV editing.
Right. As jagabo noted, for this particular task of just making simple unfiltered edits, use Direct stream copy.
Last edited by sanlyn; 10th Jan 2014 at 09:57.
VirtualDUB performs a lossless copy of the audio and video data giving you the part of the capture that's worth saving, without further loss. Using Trim in AVIsynth forces re-compression (=filesize bloat for no reason if re-saving to lossless, or loss if re-encoding to DV). Going via AVIsynth also hard-codes any DV decoder errors into the file, and (in the case of stuff transferred from actual DV tape) strips all the shooting metadata, timecode, time and date information, and error flags. VirtualDUB preserves all this.
Even though VirtualDUB is lossless, unless there's minutes of blank space, I wouldn't bother trimming it. I usually do bother because I leave the thing copying and end up with minutes (sometimes hours!) of nothing at the end of the VHS>DV capture. I never bother trimming DV-AVI transfers of actual miniDV tapes though.
Last edited by 2Bdecided; 10th Jan 2014 at 09:59.
Same reason, short blank section at front, . and about 10 mins' of overrun
Will also confirm - been using VirtualDub's "Direct stream copy" for over a decade now (wow, can't believe it's been that long) and it has never re-encoded/re-compressed anything - 100% non-destructive.
It wasn't frame accurate for MPEG-4 formats like DivX, Xvid, but that's because the key frames are further apart on those. With DV being intra-frame, accurate cutting is assured (and will not need any smart rendering).
So go ahead and use it to trim ends on your captures or make cuts, and even lossless joins as well with "File Append AVI segment".Been away for a while and busy with work the last few months so I had no time for forums. My apologies for any emails I couldn't get to in time - missed you all! :-)
Originally Posted by 2Bdecided
For camera content/tapes I can agree, since it's what's been shot, and the true digital source - unless you purposely want to edit it out (and that's a whole other debate and philosophy on the integrity of capture, etc, blah, blah, blah...).
I will comment on those captures from VHS tapes though, since it's not a direct transfer of any digital source from the tape (and much of it may be from TV, or second gen stuff, etc.), only a digital representation of it.
Honestly, I find it much less time consuming to just let it run hours on end. I just feed the machine, tape by tape, but do other stuff while it's working, in or even out of the house, then come back when it's done (or even long after). I've even fallen asleep while forgetting a capture is running too.
But that's fine. I could care less about the junk it may be capturing. (And always have good stop conditions, and it's on a dedicated capture box, anyway.)
When done, I brush through the video and cut out what I want to cut out with direct stream copy and delete the original capture string. Sometimes I find I only want, like 20 minutes, from a multi-hour capture. (Using "Job Control" is very helpful if you cut out many pieces at a time.)
I've saved so much time doing it this way, even if it was for only 20 minutes of content, as this takes minutes to cut out, instead of babysitting each capture, one by one - after hundreds of tapes, even labelled some 10-20 years ago, I still don't know for sure what's on there.
My point is that Direct Stream Copy is wonderful, and should be highly encouraged. I wish we had something like this during the old days of VHS recording (while we actually had to be attentive to each session - recording/editing/stopping/starting/etc - ugghhhh).Been away for a while and busy with work the last few months so I had no time for forums. My apologies for any emails I couldn't get to in time - missed you all! :-)
Pedantic mode on:
My friend, in his OP, said "Ready for when I want to process"
Agreed that he has a head and a tail - not my friend unless he is a dragon in disguise - but his WinDv cap.
Agreed that if he trims this in VD that does not alter the original (unless he then deletes that)
So the 'processing' ,however it is being, done will involve re-encoding. If the trim is done in avisynth then it still becomes one pass as part of the 'process'. Only if there is no intention to do ANY filtering with the cap if there real benefit in doing this in VD
Pedantic mode of:
[This Dragon will now retire to his cave for this topic ]
Well I thought it was a simple question when I asked it.