Nvidia GTX970/980 and H.265

[Fanatic]

Hello,

Just got my GTX970 a few days ago and now wondering how long you think it will be before we see the H.265 encoder being available to use?

I guess it needs a bit of work done by a number of people? Nvidia to release API/drivers for it, Twitch/Hitbox etc to support it, and OBS to use it as an encoder.

Sorry if this has been asked before. Really looking forward to better stream quality with no performance loss using NVENC and H.265.

Used OBS for a long time and it's an excellent piece of software, thank you.

 

[Sapiens]

Don't hold your breath. At the very least Flash will need to implement support for h265 before anyone can even watch it, and I'm not sure whether NVENC will be worth a crap for streaming (it's currently pretty terrible at h264 with the lower bitrates used for streaming). Even if OBS supported it right now it would be a good while before you could ever use it for streaming.

 

[Boildown]

I'm curious how h.265 encoding even made Nividia's feature list for those GPUs. In theory, if it actually worked, it could be capable of being saved to the hard drive. But even that doesn't have a lot of value, because h.264 works just fine for that, and good luck finding a video editor to do anything with the file you create. H.265 is only even wanted for streaming or as the final product you upload to the internet (for increased quality per bitrate), its not going to be a good format to save video game footage to a hard drive, because it is likely hard to edit (h.264 is pretty hard as it is) and nothing supports it.

I find it extremely difficult to believe that NVEnc encoded h.265 streaming (assuming sites like Twitch and players like Flash added support for it) would be any good, because NVEnc struggles already to keep up with 1080p60 video on h.264. H.265 is significantly harder to process, I can't even see how it would work at all and have the quality per bitrate be an actual improvement.

 

[Fanatic]

I read that the encoder in the Maxwell cards is much more powerful (X2.5 I think I read) than the version in Kepler cards. It can do 1440p60 & 4Kp60.

With all that extra power I would have thought (hoped) they could improve the H.264 encoder some more.

 

[Boildown]

Even Maxwell can barely do 1080p60 on the High Quality preset. H.265 is at least twice as CPU intensive for the quality per bitrate you get (to say nothing of getting all the improvements promised by the next-gen codec). So unless the GPU chip has some advantages over the CPU software encoder (seems unlikely) I can't imagine, even with Maxwell, that its h.265 encoding would be very usable.

 

[ZeroWalker]

So wait, they didn't improve the Quality of their H264 encoding with this release, but only sped it up?
Doesn't make much sense, as all i hear is that it looks crap.

Even QuickSync look crap which i have seen comparisons to AMD.
But Quicksync is at least acceptable to some degree (at least higher bitrates, and Haswell i think i saw), AMD looks okay, i think it was worse than x264 SuperFast which is not optimal at all, but it's still quite good (Also this is on higher bitrates).

 

[Jack0r]

Not that I know what they did, but QS made the same steps, gen1 - 2 was only speed, gen 2 - 3 was then a quality improvement, who knows what comes next :)

Small edit: Latest quicksync gen isnt bad, see my comparisons.

 

[ZeroWalker]

That's true:)

No idea where to find those;P

 

[8BitCerberus]

Don't hold your breath. At the very least Flash will need to implement support for h265 before anyone can even watch it, and I'm not sure whether NVENC will be worth a crap for streaming (it's currently pretty terrible at h264 with the lower bitrates used for streaming). Even if OBS supported it right now it would be a good while before you could ever use it for streaming.

A question I've been meaning to ask about a system with both NVENC and QuickSync available, I know of the comparisons I've seen QuickSync does look better at a given bit rate than NVENC, but if I've got the monitor I game on plugged into my Nvidia GPU, and my second monitor plugged into the onboard GPU (so the Nvidia isn't having to push pixels to both monitors while gaming), could I still use QuickSync to record gameplay?

I know I should just test it out myself, but I hadn't had the time and now I'm out of town away from my PC until next week, and this message just reminded me about it. So I thought I'd ask :)

I know x264 is the best choice for quality, but I don't want to sacrifice FPS for a minor quality bump (at 25+Mbps of course. Streaming at 3.5Mbps might be a different story though, and I do need to test that out as well).

 

[Sapiens]

You should be able to but there shouldn't be any appreciable performance impact from running 2 monitors on your NVIDIA GPU. If you're running Windows 7 then a monitor (real or virtual) needs to be connected to the iGPU, in Windows 8 this isn't necessary.

 

[8BitCerberus]

So I just did a bit of testing. I don't see any obvious difference between the QuickSync and NVENC output at 25Mbps, as I had suspected.

Testing at 3500Kbps, however, wow! Huge, huge difference. I tested all three, and QuickSync was by far the best, as in it almost looked as good as if I'd been encoding x264 around 8Mbps. Both x264 and NVENC were riddled with artifacts with any fast motion that just wasn't there on the QuickSync videos. NVENC was the worst at 3500Kbps, but x264 wasn't much better, honestly. So I think for Twitch streaming I'll certainly be using QuickSync from now on.

Now for the head scratcher though: when I choose QuickSync as the encoder, then look at the Video settings, my GeForce is still selected in the Video Adapter. But changing that to the Intel 4600 didn't seem to make a difference, visually, on my test videos. So I'm wondering what that video adapter setting is actually doing in this situation? I did notice on one test a slight increase in CPU usage when setting the Intel as the video adapter (30%) vs. keeping the GeForce as the adapter (18%). But a subsequent test had both options hitting the CPU the same at around 12%.

With NVENC chosen as the encoder, my CPU usage is around 4%, and with x264 chosen it's around 30%.

 

[dodgepong]

The video adapter option chooses what GPU OBS uses to do its rendering. It doesn't affect encoding. However, if you are using game capture, you have to run OBS on the same GPU as the game.

 

[8BitCerberus]

Ah ok, that makes sense I think. Thanks for that.