Freeware Software needed to convert mkv LQ to mkv HD Faaaaast

[RBCC]

Is there a piece of software that will convert 22 files from LQ Mkv to HD MKV super fast , I have software for this but it takes 3 days! Is there one that will do it in <1/hr ? John

[jagabo]

You can't increase the quality of a video by re-encoding it.

Most of the free converters use x264 for encoding. There's a 100 fold difference in encoding time between the fastest (ultrafast) and slowest (placebo) presets in x264. If you want faster encoding use a faster preset. If you have a recent Intel CPU with Quicksync, or a GPU with hardware encoding, you can get faster encoding using that hardware encoder.

[RBCC]

I have an and 2g on a hp laptop.
what is the fastest preset.

[jagabo]

x264 presets from fastest to slowest:

ultrafast
superfast
veryfast
faster
fast
medium
slow
slower
veryslow
placebo

There's not much speed difference bewteen ultrafast, superfast, and veryfast. But quality/size is significantly better with veryfast. Speeds slower than veryfast give slightly better quality at each step but take longer and longer to encode.

[poisondeathray]

why are you doing this? If LQ is "low quality", re-encoding it will make it lower quality . Something like "VLQ" I guess

[LigH.de]

"Fastest" solution: Playback with madVR. No conversion, just upscaled playback. Upscaling in most converters won't look much better.

[pandy]

Not necessarily VLQ, additional post processing/filtering may improve visually LQ source then recompressing this to new file may be not so bad but because OP didn't provided any information this is purely hypothetical discussion - unless case look like: recompress source with only higher bitrate and without any filtering then it may be better than LQ.

[jagabo]

I have software for this but it takes 3 days!

If you had started encoding when you posted this message you'd be done by now.

[RBCC]

What converter do you recommend? That has the speed settings for h.264?