1080p to 720p

[anirban]

What is the best way to convert 1080p MKV file movie to 720p MKV?

[Baldrick]

Best as in easiest or faster or best video quality?

I would use automkv.

[anirban]

Best means I refer to quality and also speed....So plz help me...

Also if I use Lossless option in MeGUI will it work well provided I mention res as 1280 x 720 ?

[poisondeathray]

Usually there is a trade-off between quality and speed

"Lossless" in MeGUI will be excellent quality, but the filesize will be huge -probably ~10x as large as if you used a decent bitrate or average CRF setting

[anirban]

So what shall I do to downscale 1080p MKV file to 720p in same quality! Kindly advice please! I go for quality. The source MKV file is of 4.5GB and i want to keep the output 720p file within 4.5GB. SO please advice..

[poisondeathray]

Please understand it is impossible to keep "same quality." You are losing over 2x the number of pixels when you go 1080p => 720p

I think the best you can probably do is use MeGUI, 2-pass encode using HQ-slow profile (if you want use HQ-insane, but the difference is minimal and takes >2x as long). Use the bitrate calcuator in MeGUI to size it to 4.5GB minus the audio size (You don't have to re-do the audio just extract it from the original and re-mux it with the new 720p)

[edDV]

So the problem is you can't play the 1080p MKV file ?
Any recode will lower quality in a major way. Downscale + recode will be worse still.