Variable Speed Reviewing Before Editing

[IanGreen]

Hi Everyone,
Apologies if I am posting in the wrong section, but this is my first post here, so still feeling my way.

I am looking for advice on software with which I can speed up the process of editing miles (literally) of .mp4 and .mov dashcam footage.

Whichever software I end up with, MUST have the facility for increasing the speed of "reviewing" by x4 x8 or even x16 times otherwise, if I am forced to review at the "apparently standard" speeds of software I have trialled so far ---- I shall be an extremely old man by the time I finish.

So that I don't waste anyone's time --- I have tried most of the standard dashcam viewing software (none of which provides editing) and, although Registrator Viewer fits the bill in many respects, it's ability to vary the speeds (other than reducing) is haphazard at best.

I wish also to avoid Corel/Pinnacle software due to very poor experience(s) with their support Agents.

All suggestions gratefully received,

Thank you,

Ian

[redwudz]

For freeware, try AVIDemux. It works fine with my .Mov dashcam video and has a 'wheel' to scrub through the video.

Other members can probably suggest some commercial editor software.

And welcome to our forums.

[IanGreen]

Hi redwudz, and thanks for your quick reply and my "welcome to the Forum" greeting -- both appreciated.

It sounds as if you are doing similar things as me with the dashcam videos, so I shall go and download AVIDemux and give it a whirl !!

Best regards,

Ian

[IanGreen]

Hi again redwudz,

I don't know if I am missing something, or whether it isn't working right, but I have installed AVIDemux, and all I can get it to do is play at a constant speed. i.e. a 5 minute video takes 5 minutes to review.
I have tried scrolling the "wheel", both backwards and forwards with my mouse wheel, but it appears to have very little or no effect on speed at all.

Any ideas please?
Ian

[locotus]

If just want to speed-up or slow-down playback of files
for any particular purpose, VLC can do that in playback > speed.

[jagabo]

I don't know if I am missing something, or whether it isn't working right, but I have installed AVIDemux, and all I can get it to do is play at a constant speed. i.e. a 5 minute video takes 5 minutes to review.

The scrub wheel doesn't effect playback speed. It's for scrubbing (moving) through the video while it's paused.

One way you can get faster playback in AviDemux is to change the frame rate via Video -> Frame Rate. For example, if a video is 30 fps and you change the frame rate to 120 fps it will play 4x faster (audio will be out of sync). Don't try to edit in that mode though. In fact, don't try to edit anything with AviDemux -- it will crash at the most in opportune time.

[poisondeathray]

I guess it also depends on what type of "editing" you are doing. Is it simple cuts only? or slightly more complex editing, maybe things like effects, titles, transitions, overlays, multiple source compositions, color correction, etc.. ?

Might be overkill if you're only cutting, but commercial editors like premiere pro, avid media composer, fcp, etc... can all do this incremental speed forward or reverse. But for most input formats they require re-encoding. But if you were doing any of the other things like color correction, overlays etc... those would require re-encoding anyways.

Which leads to the next point - if you just want cuts, something like videoredo might be a better option. It doesn't have a variable playback speed per se, but there are 30sec, 2min jump keys, and a shuttle seek, and a seek bar. A major benefit is it can stream copy the original, so no quality loss (except a few frames if you cut between a GOP), and much faster than re-encoding.

[smrpix]

Long-GOP video, due to its structure, is notoriously bad at playing at sustained high speed, even in high end editors. It quickly freezes and (often) crashes.

[raffriff42]

Yes, Vegas Movie Studio has a problem with long-GOP footage (it pauses a lot), although it shuttles through intra-only footage just fine.

IanGreen, try this AviSynth script:

#Source(...) 
ShowFrameNumber(size=Height/12, x=Width*7/16, y=Height/2) 
AssumeFPS(FrameRate * 16).ChangeFPS(FrameRate, linear=false)
Amplify(0) ## silence audio (it's out of sync anyway)
return Last

EDIT to use this, you would scan the video at 16x speed, pausing wherever you spot something of interest. Note the frame and continue scanning. Then go back, comment out the middle three lines, reload the script and the video will play at normal speed. Now you can seek directly to the frames you noted in the previous step.