http://www.openshot.org/
Este soft ademàs de gratuito, es muy completo:
Cross-platform (Supports Linux, OS X, and Windows)
Support for many video, audio, and image formats (based on FFmpeg)
Powerful curve-based Key Frame animations
Desktop integration (drag and drop support)
Unlimited tracks / layers
Clip resizing, scaling, trimming, snapping, rotation, and cutting
Video transitions with real-time previews
Compositing, image overlays, watermarks
Title templates, title creation, sub-titles
3D Animated Titles (and Effects)
SVG friendly, to create and include vector titles and credits
Scrolling motion picture credits
Solid color clips (including alpha compositing)
Support for Rotoscoping / Image sequences
Advanced Timeline (including Drag & drop, scrolling, panning, zooming, and snapping)
Frame stepping (key-mappings: J, K, and L keys)
Video encoding (based on FFmpeg)
Digital zooming of video clips
Time-mapping and Speed changes on clips (slow/fast, forward/backward, etc...)
Custom transition lumas and masks
Audio mixing and editing
Presets for key frame animations and layout
Ken Burns effect (artistic panning over an image)
Digital video effects, including brightness, gamma, hue, greyscale, chroma key (bluescreen / greenscreen) , and many more!
OpenShot provides extensive editing and compositing features, and has been designed as a practical tool for working with high-definition video including HDV and AVCHD .
un saludo