Doom9's Forum - View Single Post - Number of Ref frames / amount of compression

Lathe · 27th February 2020, 06:51

Hello all!

I asked something similar last year, but I don't think I asked it very well

So, I didn't quite get the answer that I THINK I need.

In doing a 1 Pass ABR compression for a Blu-ray where there is VERY LITTLE compression being done. Say for example a file is being compressed from a size of 25 Gigs to 22 Gigs. The resulting encode will be around a 24,000 bitrate, which is pretty decent. Normally, I like to thrown in a couple of little 'Tweaks' such as me-hex and subme-6 so that I can activate both the Psy and Trellis settings and give them a little bump. With this in mind using a VeryFast setting, and YES I am aware of the parameters included in that preset, since the resulting encoded bitrate is pretty high, is the default ref-1 setting 'good enough' or would adding an additional 'Tweak' setting the ref frames higher (2-4) make any discernible visual difference in your opinions.

In other words, should I just leave the ref-1 setting, or should I bother to increase the refs since the resulting bitrate will be fairly high?

Thank you kindly for any thoughts and input. Again, I am asking for your OPINIONS based on the above. With such little compression at 1080p is there any necessity to increase the ref frames higher than the ref-1 that the preset calls for. I am only interested in whether you feel the picture quality would be affected/improved enough to bother. I know the ref frames are primarily a factor of compression, so with such little compression will it matter visually?

Thanks!

27th February 2020, 06:51	#1 \| Link
Lathe Registered User Join Date: Aug 2005 Posts: 1,100	Number of Ref frames / amount of compression Hello all! I asked something similar last year, but I don't think I asked it very well So, I didn't quite get the answer that I THINK I need. In doing a 1 Pass ABR compression for a Blu-ray where there is VERY LITTLE compression being done. Say for example a file is being compressed from a size of 25 Gigs to 22 Gigs. The resulting encode will be around a 24,000 bitrate, which is pretty decent. Normally, I like to thrown in a couple of little 'Tweaks' such as me-hex and subme-6 so that I can activate both the Psy and Trellis settings and give them a little bump. With this in mind using a VeryFast setting, and YES I am aware of the parameters included in that preset, since the resulting encoded bitrate is pretty high, is the default ref-1 setting 'good enough' or would adding an additional 'Tweak' setting the ref frames higher (2-4) make any discernible visual difference in your opinions. In other words, should I just leave the ref-1 setting, or should I bother to increase the refs since the resulting bitrate will be fairly high? Thank you kindly for any thoughts and input. Again, I am asking for your *OPINIONS* based on the above. With such little compression at 1080p is there any necessity to increase the ref frames higher than the ref-1 that the preset calls for. I am only interested in whether you feel the picture quality would be affected/improved enough to bother. I know the ref frames are primarily a factor of compression, so with such little compression will it matter visually? Thanks!