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Blurayhd
4th June 2019, 05:13
Hi guys I really have yo ask what is better, I mean what do you recomend and why, encoding with h264 CPU mode or H265 NVec ?

Or is not matter what both are same?

Thank you in advance!!

ChaosKing
4th June 2019, 08:31
h264 cpu should still produce better quality. Most h26X GPU encoders can't match the quality of the cpu version. So if quality is important to you -> h264/h265 cpu. If you need a very fast encode -> h264/h265 GPU (NVenc)

EDIT: https://www.youtube.com/watch?v=BV5btdqQfu4

Asmodian
4th June 2019, 10:41
The newest version of NVenc H.265 is much better than it used to be but it depends on what you want. For low bitrate fast encodes I would use H.265 via NVenc (assuming it is a 1660+) but for archival high bitrate I would use x264.

nevcairiel
4th June 2019, 10:57
Especially the turing encoders are definitely decent for stuff like quick encodes to put on your mobile, or even live streaming to another device on the fly (ala Plex, etc). I agree that its not ideal for archival.

Blurayhd
5th June 2019, 01:16
Hi guys and excuse me but I donŽt get it, youŽre saying that the x264 is better than x265? I mean for MKV movies that I like to keep, and what you said the differenc between NVec and without? for both x264 and x265?

Thank you in advance!!

Asmodian
5th June 2019, 03:01
The choice you presented was between H.265 via NVenc or H.264 via software, wasn't it?

H.265 is better quality than H.264 only when quality is constrained by bitrate. NVenc H.264 or H.265 output is still lower quality than x264 or x265. I would use H.265 if using the newest NVenc hardware but I still prefer slow software encoding due to the quality benefits.

Blurayhd
5th June 2019, 04:22
The choice you presented was between H.265 via NVenc or H.264 via software, wasn't it?

H.265 is better quality than H.264 only when quality is constrained by bitrate. NVenc H.264 or H.265 output is still lower quality than x264 or x265. I would use H.265 if using the newest NVenc hardware but I still prefer slow software encoding due to the quality benefits.

Thank you again Asmodian, now if I understand you mean the lower quality is because the NVenc so you are saying if I encode with 265 but CPU (not Nvec) IŽll get better quality than 264?

And for keeping my MKV movies that I really want is better with 265 (CPU)?

Forteen88
5th June 2019, 11:27
NVenc is OK to use if you have any of the Nvidia-graphicscards that got "HEVC B Frame support" on this list,
https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

Video-encoders with no B-frame support should be avoided for quality.

Blurayhd
5th June 2019, 16:04
NVenc is OK to use if you have any of the Nvidia-graphicscards that got "HEVC B Frame support" on this list,
https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

Video-encoders with no B-frame support should be avoided for quality.

Let me see if I get it, I have GeForce GTX 1080 Ti and is NO on list

All I wish to know if always encoding with CPU mode what is better quality/recomend? 264 or 265?

Asmodian
5th June 2019, 18:29
All I wish to know if always encoding with CPU mode what is better quality/recomend? 264 or 265?

This question does not have a true answer, it depends. :p

At very high bitrates x264 can offer at least the same quality, at low bitrates x265 is better. x265 is a lot slower too. I still use x264 for archival encodes.

My recommendation:
You want minimum size while still looking good? Use x265
You want as good as possible while not worried about the size very much? Use x264

Edit: For something in the middle I would only use x264 if x265 was too slow.

Blurayhd
6th June 2019, 21:58
This question does not have a true answer, it depends. :p

At very high bitrates x264 can offer at least the same quality, at low bitrates x265 is better. x265 is a lot slower too. I still use x264 for archival encodes.

My recommendation:
You want minimum size while still looking good? Use x265
You want as good as possible while not worried about the size very much? Use x264

Edit: For something in the middle I would only use x264 if x265 was too slow.

Thank you very much finally I got clear

benwaggoner
11th June 2019, 16:47
Thank you very much finally I got clear
It's really about quality @ bitrate @ speed.

Allowing higher bitrates means encoding can be much faster.

If speed is a constraint, the real question is, configured to run at the same encoding speed, does x264 or x265 look better. x264 veryslow and x265 slow might be of equivalent speed, so which looks better?

Note the speed differentian between x264 and x265 is going to vary a lot depending on hardware and frame size. With bigger frames x265 can support more parallelization. x265 uses AVX2 more effectively than x264.

Going from an Intel gen 6 to Intel gen 9 might make x264 4x faster and x265 10x faster since x265 can use the new instructions and extra cores more.