I can't set a better quality using NVENC+H265

Discussing about advanced video encoding techniques including GPU encoding, distributive encoding and segmental encoding. Topics are not limited to MediaCoder.
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psychok9
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I can't set a better quality using NVENC+H265

Post by psychok9 » Sat Aug 01, 2015 8:14 am

I'm a 980TI owner, and I'm using mediacoder with NVENC support.
The problem is that I can't set a great quality and high bitrate.
For example: I have a music video with 3,54GB size (H264, 1440x1080p,39mins).
If I convert it to H265 codec, I get always a ~600MB~ file.
I've tried to use VBR with 16MBit bitrate, CF 1, CF 0, without success.
How can I improve the bitrate? H265 permits to half the size of the file, with the same quality... But with 600MByte/file I get worse quality.

jakub
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Re: I can't set a better quality using NVENC+H265

Post by jakub » Wed Aug 05, 2015 9:02 am

I had the same problem. The solution for me was:
1. Open console (Toggle console window F6).
2. On the "video" tab click on button "rate mode".

You will see the same setting as in main window. Only every setting available at the same time.
Now by try and error you can set the settings in that window and, then start encoding and observe the commands in console window. Specifically parameters of those commands do matter.

I played with this tool for only 3 hours so far and I experience the same problem like you. I had some success in first 10 minutes but then after playing with the settings it all got to the same LQ file output no matter what I choose for that H265 and NVENC.

And now since I know the above method will play with it more.

sheby1911
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Re: I can't set a better quality using NVENC+H265

Post by sheby1911 » Thu Aug 06, 2015 11:48 am

I've got the same problem, the bitrate and the file size is the same no matter what I set.

Pls help!

psychok9
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Re: I can't set a better quality using NVENC+H265

Post by psychok9 » Sun Aug 16, 2015 2:21 am

I'm trying any options. The encoder seems ignore CF, VBR or ABR setting.
"QP for all frames" on advanced makes huge files...

Are you looking for a fix?

stanley
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Re: I can't set a better quality using NVENC+H265

Post by stanley » Thu Oct 08, 2015 6:36 pm

Fixed
When things work together, things work.

yobooh86
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Re: I can't set a better quality using NVENC+H265

Post by yobooh86 » Mon Mar 06, 2017 3:20 am

I have the same problem...
Cannot force better quality with Nvenc and Two pass/VBR expecially with gray background I have extreme unwanted compression.
The only solution for me it's to set constant QP... even wit an extreme VBR quality i have the same blocky gray area as shown in the image I posted (left side)
PLease HELP MEEEE!!!

http://imgur.com/6vlDXra

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