Hardware Optimizations and 2-Pass-Encoding

[mue.mat]

Hello
To get better conversion results I use "2-pass-encoding" and "Use best video quality settings" for BluRay-conversion.
But to have much better conversion speed I enable hardware optimization to use Nvidia-Cuda-hardware decoder.
Conversion is about 6 times faster than without hardware optimization and video quality is good.
What I don't understand is:
Why are "2-pass-encoding" and "Use best video quality settings" NOT WORKING if hardware optimization is ENABLED?
Without hardware optimization "2-pass-encoding" and "Use best video quality settings" are working properly, but conversion speed is very slow.
Can you help me? I don't know if enabled hardware optimization reduces video quality because "2-pass-encoding" and "Use best video quality settings" are not possible to use.
Which settings do you recommend me to have optimal conversion speed and best conversion quality?
Thanks in advance
mue.mat

[JJ]

There are several settings that can not be ON with hardware encoding due limited instruction set on hardware encoders.
In short - hardware is brute force encoding, does simple tasks really fast while CPU can do more detailed tasks but slower.

[mue.mat]

Thanks for quick answer.
That means: Hardware encoding is (due to my grafic card) much faster with reasanable video quality, during CPU encoding is slower but gives better video quality (while using "2-pass-encoding" and "Use best video quality settings" for BluRay-conversion)?

[JJ]

Thanks for quick answer.
That means: Hardware encoding is (due to my grafic card) much faster with reasanable video quality, during CPU encoding is slower but gives better video quality (while using "2-pass-encoding" and "Use best video quality settings" for BluRay-conversion)?

Basically yes.

If original is really good quality, then in most cases you do not see any difference between HW and SW encoding, only difference being encoding time.