Can Multiquence record backwards?

General discussions and questions about MULTIQUENCE
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MichaelBeere
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Can Multiquence record backwards?

Post by MichaelBeere » Fri Oct 29, 2004 5:13 am

I has an idea for a video sequence which requires a section of video to be run backwards. It could be done quite easily in the old days of film but I have not found a program that allows this to be done with digital images.

GoldWave Inc.
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Re: Can Multiquence record backwards?

Post by GoldWave Inc. » Tue Nov 02, 2004 2:10 am

Video files are encoded in such a way that it makes decoding them in reverse difficult. Usually only differences from one frame to the next are stored. To play in the forward direction, you start with the first frame (key frame), then add the differences between frame 1 and 2 to recreate the frame 2, then add the differences between frame 2 and 3 to recreate the frame 3, etc.

For playing in reverse, there is no easy way to start with frame 3. You'd have to recreate that frame from all of the previous frames. While it is technically possible to do for some encodings, it can be very slow to process, especially if there are dozens of frames to recreate between key frames.

Chris

MichaelBeere
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Recording backwards

Post by MichaelBeere » Thu Nov 04, 2004 3:19 am

So is the answer then to record the digital film onto a video tape and then re-record the secgment whilst playing it in reverse mode on the VCR?

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Re: Recording backwards

Post by GoldWave Inc. » Thu Nov 04, 2004 5:27 pm

Some high end programs can process video files to create a reverse video (possibly Premiere or Vegas). If you have a VCR that plays clear video in reverse at normal speed, then that would work as well.

Chris

tgw
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Post by tgw » Sun Jan 30, 2005 12:59 am

Reverse video is very easy, if you know how of course.
Download & install the free tool AviSynth2.
Create a text file in the AviSynth folder, give it an ".avs" extension.
In that file, put the line;

Reverse(AVISource("...full path to video file"))
For example;
Reverse(AVISource("d:\KidsJumpingInPool.avi"))

Double click on the file and poof, it's done. If Windows doesn't know what to do with that file's extension, tell it to run it with AviSynth2.

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