Tracker on Linux

Tracker is a Java-based application and will therefore run on Linux as long as Java 5.0 or higher is correctly installed. QuickTime is not available for Linux, however, so Tracker cannot open QuickTime movies directly. Instead, Quicktime and other digital video formats must be converted to either jpg or png image sequences or animated gifs. If you have access to a Windows or Mac computer, you can use Tracker itself to do the conversion. If not, you can use FFmpeg to convert to an image sequence.

Note: the animated gif conversion process described below is untested. If you are a Linux user and can recommend any better method(s) please contact me at dobrown at cabrillo dot edu.

1. Converting a video to a numbered image sequence using Tracker on Windows or Mac

- On a Windows or Mac computer, use Tracker to open the video.
- If desired, open the clip inspector and set the start frame, end frame and/or step size.
- If desired, apply one or more video filters to optimize the video image.
- Choose the Video|Save Clip As|Image Sequence menu item, assign a file name and choose an image type (jpg or png). Tracker automatically determines the required number of digits for the numbering.

2. Converting a video to a numbered image sequence using FFmpeg on Linux

- Download FFmpeg from http://ffmpeg.mplayerhq.hu/.
- On the command line, enter "ffmpeg -i <movie-file> <image-name>%03d.jpg" or "ffmpeg -i <movie-file> <image-name>%03d.png" to create a numbered sequence of images.
- The %03d format code in the ffmpeg command above produces three-digit numbering ("frame001.jpg, frame002.jpg, ..."). Single-digit numbering ("frame1.jpg, frame2.jpg, ...") will work for sequences up to 9 images and two-digit numbering ("frame01.jpg, frame02.jpg, ...") for up to 99 images. Very long image sequences can require huge amounts of memory and in some cases may cause Tracker to freeze.

3. Opening or importing a numbered image sequence into Tracker

- Choose the File|Open..., Video|Import... or Video|Replace... menu item and select the first image in the sequence.
- If a "Load Image Sequence" dialog pops up, click on "Entire Sequence". This will load the entire sequence into a single video in Tracker.
- Very long image sequences can require huge amounts of memory and in some cases may cause Tracker to freeze.

4. Converting a video to an animated gif using Gimp on Linux

- Download Gimp from http://www.gimp.org/unix/.
- Convert the video to an image sequence as described above.
- Merge the images into a single animated gif file using Gimp.