How do I speed up DVD video?

[whoisus]

Hi,

I'm making a film focused on certain types of cell division. The divisions take hours and I need to edit the video to speed it up ~60x however I can only record to DVD in real time. Are there any programs that will do this and guides on how to edit the speed of a DVD video?

Thanks!

[edDV]

Hi,

I'm making a film focused on certain types of cell division. The divisions take hours and I need to edit the video to speed it up ~60x however I can only record to DVD in real time. Are there any programs that will do this and guides on how to edit the speed of a DVD video?

Thanks!

Various ways. AVIsynth will allow deleting frames time lapse style.

Many pro level edit programs will filter (interpolate) a variable frame rate. You can even modulate velocity with bezier curves or other spline interpolation.

[whoisus]

Various ways. AVIsynth will allow deleting frames time lapse style.

Many pro level edit programs will filter (interpolate) a variable frame rate. You can even modulate velocity with bezier curves or other spline interpolation.

Deleting frames to create time-lapse style isn't really an option as the focus of my work is creating a continuous film due to the fact that currently only time-lapse videos are available.

Could you please name some of the pro level edit programs/link me to guides? I'm new to this and don't really know anything yet as all I've done in the past is use DVD Shrink, so I didn't understand your final sentence at all.

[guns1inger]

What do you intend to play this video back with ?

If you are hoping to transfer the footage back to DVD then you are limited to 25 fps (PAL) or 29.970 fps (NTSC). The only way you can make the footage appear to be faster is to either delete frames, or blend several frames together into one. If you had filmed the division originally to get faster playback, you would have found that the camera did so by taking less frames per second - which is the same as taking frames out afterwards. That is how time-lapse cameras work. Frames could be as much as several seconds or even minutes apart.

If you are going to use a fast PC then you may be able to use avisynth or even just a good player to get playback at up to 200 fps, which is 8x PAL. There is no way you are going to get 60x without throwing away a lot of images.

As for pro software, something like Twixtor is probably the go.

[whoisus]

What do you intend to play this video back with ?

If you had filmed the division originally to get faster playback, you would have found that the camera did so by taking less frames per second - which is the same as taking frames out afterwards. That is how time-lapse cameras work. Frames could be as much as several seconds or even minutes apart.

I intend to play the video back on DVD.

I'm not using a time lapse camera: there is a video camera attached to a microscope that feeds live images through a Blu-ray player + Hard Drive recorder. The video is captured live and can only be removed from the device by being burnt to DVD/Blu-ray disc that's why I need to know how to speed up that footage. I've realised that the equipment is probably not optimal for this, but I'm not in control of that I've just got to get the job done.

Can you direct me to any guides on how to use avisynth to speed up the DVD video as much as possible?

[Gavino]

To speed up 60x in Avisynth, it's as simple as:

SelectEvery(60, 0)
AssumeFPS(25)

For NTSC instead of PAL, change the 25 to 29.97 (or 30000.0/1001).

[jagabo]

SelectEvery(N,0) tells AviSynth: for every N frames, keep the first one (number 0) and throw away the rest. So with N=60, only one of every 60 frames is retained. You now have 1/60 as many frames but AviSynth also adjusted the frame rate by that amount too, to maintain the running time. So the frame rate is now 25/60, or ~0.417 fps. If you were to watch this video you see a new frame every 2.4 seconds. The full running time is still the same as the original.

AssumeFPS(25) tells AviSynth to assign a new frame rate to the video, in this case increaseing the frame rate from ~0.417 fps to 25 fps. The video now has the same frame rate as the original (25 fps) to maintain DVD compatibility, but 1/60 as many frames. Ie, it plays 60 times faster than the original.

In theory, you can increase the frame rate of the original video to 1500 fps (AssumeFPS(1500)) to achieve the same 60 fold increase in playback speed. But nothing can display a 1500 fps video. It's certainly not DVD compatible.

[MOVIEGEEK]

Or just use a NLE such as VideoStudio 10+.

[jagabo]

If your source is noisy and but otherwise slow moving you can average together mulitple frames to reduce the noise.

[nic2k4]

I just open the video in VirtualDubMod and change the frame rate, then frameserve back into TMPGenc to re-encode to MPEG2.

[edDV]

I was thinking Adobe Premiere Pro, Apple Final Cut Pro or Sony Vegas Pro.

All do splined velocity. You can even reverse speed. Each has a different user interface. Try the demos.

http://vimeo.com/9297596
http://www.youtube.com/watch?v=8cAH-luH8TY
http://vegas.digitalmedianet.com/articles/viewarticle.jsp?id=946322-1&afterinter=true

Google "Vegas Velocity envelope"


PS: If you don't want to learn the software, any post house could crank this out in short effort, just expect long render time if HD.