Released for 64-bit Linux only.
Fixes an issue where there could be a color shift on the top of the image at higher resolution then HD in project higher than 8 bpc.
This is a 64b fix only. Note the plugin has been renamed Twixtor and DesktopTwixtor without the number in the name so there is no more issues with differing Sparks names for Twixtor the next time you upgrade. If you need to run burn on 32b, copy and rename the 32b burn Sparks so the number in the name matches. You can rename the plugin without it having any adverse effects.

Released for 64-bit Linux only. Fixes a bug with licensing on 64-bit Linux systems.
If you need to run burn on 32b, copy and rename the 32b burn Sparks so the number in the name matches. You can rename the plugin without it having any adverse effects.

Added support for 64 bit Discreet Systems for Irix.
After upgrading your Irix plugins to Twixtor 4.5.2, you will also need to make sure any Burn licenses are also updated to Twixtor 4.5.2.

Linux support added.
Fixed a problem with some values for the InvMatteChoke setting that caused layers to be incorrecly calculated.
Fixes a problem with "source" time being one frame off.
New optimized Batch Mode is 2 seconds per frame faster.
Update required by IRIX users to use Burn

Completely rewritten motion estimation engine. Twixtor is much more accurate, tracks objects farther, and exhibits fewer artifacts when there are objects crossing in the scene.
Support for marking material so that Twixtor does not motion-interpolate inappropriately across a cut or other transition, allowing Smoke and Fire users to quickly setup a retiming for a long sequence with multiple cuts without having to cut it into pieces first.
Contains an option to remove motion blur when slowing footage.
New warp modes Forward Warping and Inverse Warping with Smart Blending (as seen in RE:Flex) to avoid artifacts at the edges of the frame.
Option to switch between Source time, Output Time, Foreground and Background views.