H.265 encoding seems very slow

[ruzun]

My 30 day trial for Adobe Premiere CC was about to expire so I went ahead and signed up for the one year plan.  This allowed me to start exporting H.265 HEVC files for the first time.  I have an 8 core i7 5960X running at 4.1 GHZ with 32 GB of RAM and an Nvidia GTX 980 video card so it's a reasonably fast system.  My gosh the exports are slow compared to H.264.  Using the default settings to export a 30 sec 4k file seemed to take forever, and the computer slows down a lot since all 8 cores seem active during the export, all 16 threads to be precise.

When I went to Max Quality and render at max depth the thing seemed to almost lock up.  It took over 5 mins just to cancel the export that would have taken who knows how long. 

The files I get are fine, but playing back on my PC the files stutter and drop frames at first, under windows 10.  Playing back from a USB drive on my Samsung TV the H.265 plays smoothly, but doesn't really look any better than the H.264 file.

Is there any way to speed up HEVC exports?  Is it this slow for everyone?

-Roger Uzun

[ruzun]

It's the Quality dropdown in the bitrate settings portion of the H.265 export window.  If you choose HIGHEST it will basically render your computer useless.  You can choose HIGHER and it is a very slow export but it does progress.  It would take hours to export a 30 sec video I think with it on HIGHEST.  I can choose 60mbps, use maximum render quality, and max bitdepth and as long as I choose HIGHER or lower in the dropdown quality the export is slow, but not so slow that it hijacks the entire PC and takes hours.

Has anyone run tests to see what the diff in encoding quality of H.265 is between the GOOD, HIGHER, and HIGHEST dropdown quality menu options in the H.265 export window?

-Roger Uzun

[greggyp89]

yes i just encoded an h265 4k hevc hdr video that was 9:50 seconds at 100 CBR higher setting and its going to take over an hour and a half. just to give you an idea i have i have brand new computer. its a threadripper 1950x 16 cores 32 threads, gtx 1080 ti, 32 gb ram 3000mhz, and 512 gb nvme ssd for boot drive and render......

[vigilant_spb]

try another codec, Daniel2 for example, it's faster (but no VR support)

[Foxtrot25]

Once you have it rendered, boy is it sweet. Youtube supports it and playback looks mint!

[excited_Genie16B8]

I've noticed the same, H.265 takes noticeably longer than H.264.

I'm not at all surprised by that.  It is a more computationally intensive codec.  All else being equal, the only way to speed up exporting that would be a faster CPU.

One of the benefits of H.265 is that you can get the same quality as H.264, but with a smaller file.  That becomes important when trying to fit 4K content into a disk, over the air, and via streaming.  But you probably wouldn't notice much quality difference without some demanding subject matter (rushing water, leaves blowing in the wind, etc) and a significant difference in the bitrates.

Or let me put it another way.  If you had any such demanding material, and an H.264 export couldn't quite handle it (showing artifacts), than an H.265 export at the same bitrates probably would.

[ruzun]

Then there's the issue of playback on a PC.  Does anyone know of a media player that can playback 4k HEVC files smoothly on a PC.  Mine play but can be stuttery depending on the scene.  On my Samsung 4k tv they play smoothly without stutter or frame dropping, but on a PC using VLC or the default media players, it really depends on the complexity of the scene.  Complex scenes just drop frames and stutter no matter what I do.  I have a fast 8 core i7 PC with an Nvidia GTX 980 card and latest drivers.

-Roger Uzun

[excited_Genie16B8 · Accepted solution]

Does anyone know of a media player that can playback 4k HEVC files smoothly on a PC.

Global Potplayer

[ruzun]

And just like that, playback problem solved!  Thanks Jim Simon, Global Potplayer handles 4k HEVC files easily, unlike windows 10 by default, or VLC!

[excited_Genie16B8]

Glad I could help.

(It's actually called just PotPlayer, though.  The Global refers to the version of the web site I linked, as they have more than one site.)