What free app to change cold blue tint and sharpness of video clips?

[Firewire60]

Anyone suggest apps, preferably free, to change the cold blue tint of highly compressed MKV video clips and make them warmer and perhaps make them slightly sharper while keeping them fairly small. They are 260 MB MKV video clips

Cheers

[LigH.de]

Tints could be handled by AviSynth: Merge(last, ColorYUV(autowhite=true)[, weight]) for simple autocorrection, or try to measure and tweak manually if you know how to (e.g. use Histogram).

But "make them slightly sharper while keeping them fairly small" is a hard task. Sharpening worsens the compressibility. And it doesn't recover lost details. To keep it reasonable, maybe try LimitedSharpenFaster. Any recompression will reduce the quality anyway, even if you increase the bitrate.

[Firewire60]

Thanks for comments LigH.
When i install it i can't find an exe file to start it.
Where is its start file?
Cheers

[LMotlow]

When i install it i can't find an exe file to start it.
Where is its start file?

Doesn't really have a start file, but the main working innards are in Windows/System32/avisynth.dll. To get it to run, start looking here: http://avisynth.nl/index.php/Getting_started .

Better yet, in your XP machine click START -> All Programs -> Avisynth 2.5 -> Avisynth Documentation. That'll get you to exactly the same page you'd see on the internet link.

I have to agree with LigH.de's post. If you start with highly compressed video, you're in for a quality loss on re-encoding. Trust us: if you alter color balance and/or sharpen and/or denoise a video, you have two choices (only). Either re-encode it, or archive it as a lossless decoded file.