How can I view videos by one hundredth of a second?

July 3, 2008 5:12 PM

Do you know of a program for viewing videos that allows tracking of the timings at the level of a one hundredth of a second?

I can track my musical events at that level, but watching videos in most programs, it is only possible to see the second timings, without further breakdown. Any suggestions?

posted by perpetualstroll to technology (8 comments total)

Yes, and no.

There are no (conventional) viewing of video at <3>
So, the smallest increment you could watch is at 1fps, or about 1/30th of a second. I got VLC player down to (I think) about 8fps.
posted by filmgeek at 5:24 PM on July 3, 2008

Is there a setting in VLC that lets you see the time breakdowns further?
posted by perpetualstroll at 5:32 PM on July 3, 2008

There is no time breakdown further, as far as I know.

That is, video is generally recorded at something along the lines of 24 fps, or 30 fps. Viewing each frame individually would only give you that resolution.

If you're concerned about sync, there might be a way to have a player program show each frame for a predetermined length of time, and then do the same for the audio? That's very speculative, though.
posted by Lemurrhea at 5:50 PM on July 3, 2008

Are you sure that you know what you are asking? You could import your video into a program like After Effects, and use a good optical flow frame interpolater like the plugin that ReVisionFx sells, and thereby get meaningful timings at more resolution than 1/60th (video interlace) of a second.

It is true that when editing sound to film 1/24th or 1/30th can seem like an awfully crude and arbitrary quantum. Editors usually "eyeball" it (earball?) for the subframe positionings.
posted by StickyCarpet at 5:57 PM on July 3, 2008

The digital representation of sound and video are two very different processes---a good digital converter or software will create at least 44100 samples per second (that's the basic rate; you can go as high as 96kHz or 192 kHz). Video, on the other hand, is usually 24 or 30 fps (actually, 29.97). You can't get more precise, simply because at that level what you see are still frames.
posted by ddaavviidd at 6:08 PM on July 3, 2008

If you just want timecode on your non-100fps video, try VirtualDub
posted by rhizome at 6:28 PM on July 3, 2008

If you want to get technical about it , analog video, such as NTSC, PAL, or SECAM does have an "instantaneous" value. That instantaneous value would be the brightness level and positioning of the CRT's electron beam at that point in time, or, if you want something more "useful" the amount of field drawn up to that point.

The graniest full field (not frame, a frame being two interlaced fields) resolution you can get from NTSC would be 1/60th second, though (actually, it's 60/1.001 Hz for colour video, black and white runs at 60 Hz). The other standards are somewhat less, with PAL being 50 Hz, for example. Using PAL as an example, 1/100th of a full second of video would yield you (at best) 1/2 of a field. At worst, you would get maybe 1/3 of a field if you caught the full vertical retrace (I'd have to consult my TV signal books to give you anything more accurate).

If you're working with digital video, the same things apply, sort of. The difference being no retrace, and no partial fields. Your digital decoder won't know how to deal with 1/2 field/frame of data. :-)

If you ever download a movie that was swiped from a master with the timecode on it (I think one of the star wars rips was like this), if you step frame by frame you'll notice the seconds jump in 4s or 5s, since movies are at 24 fps.

BTW: Fun fact! PAL sucks because all your movies play ~4% faster. I'd rather play with my tint knob than have the pitch wrong on all my movies. (Okay, now with all this new fangled digital stuff they've probably fixed this.)
posted by shepd at 7:10 PM on July 3, 2008

Alternate fun fact! NTSC sucks because of the 2:3 pulldown/interpolation of 24fps material. I'd rather put up with the continuous 4% pitch change (which these days is usually eliminated with DSP pitch correction techniques, though that can lead to other artifacts) than the on again/off again NTSC judder on pans and movement.

Really fun fact: I've been over this with friends from NTSC countries, both in the abstract and whilst sitting watching NTSC DVDs on my multistandard player & TV, and come to the conclusion that they just don't see it. They're used to it, just as people in PAL countries are/were used to the 4% pitch change. Growing up with it leads you to tune it out. These same friends were at first really annoyed by the 50Hz flicker of lighting here, but learnt to tune it out after a few weeks.

In other words: your favourite AC line frequency sucks...

IIRC, Media Player Classic can be configured to show timings in hh:mm:ss:ff, but I can't check for sure at the moment because my PC has died.
posted by Pinback at 10:47 PM on July 3, 2008