Did i waste my time and space ?

[leftspeaker2000]

I have been converting my Stargate collection for sometime now. I am just taking it slow. The average vob for an episode is around 1.4bg and I have been converting then to roughly 510mb using megui with a 2pass encoded and original audio which is on average 130mb.

I was curious so I tried constant quality of 20 and got a file size of around 270. Whilst this will change between episodes if the majority was in this ball park have I wasted space and time doing a two pass encode ? . The 2pass encoded usually takes 10 min then another 45 whilst the constant quality took around 48. Whilst I wont go back an redo them since I am already up to around 71gb and numerous episodes in I was just curious what others thing. Push on with constant quality or just stick with what I am doing and make everything uniform size wise ?

[jagabo]

I always use constant quality encoding. That way I know what the quality will be. I don't care about the exact file size. With x264 I use --CRF=18. For grainy sources I add --aq-strength=1.8.

[mh2360]

If memory serves, the first two seasons of SG-1 are *very* grainy, unless you have a cleaned up remastered version. Using CQ on those might even make them bigger.

[leftspeaker2000]

Your right mh2360 the first season of stargate is pretty grainy. I might give CFR18 a ago for the next episode and see what happens. What does aq do just reduce noise ?

[jagabo]

What does aq do just reduce noise ?

The opposite -- it retains noise. It prevents posterization artifacts, especially in dark areas, the biggest weakness in x264 (and most other high compression codecs). See the clips in this post for examples of the problem:

https://forum.videohelp.com/threads/345427-Handbrake-Should-i-leave-it-on?p=2156674&vie...=1#post2156674

With CRF encoding the bitrate will increase substantially. With bitrate based encoding the quality of bright clean areas will decrease to increase quality in dark noisy areas.

[leftspeaker2000]

I am in two minds now it would appear that two pass might give you consistently better quality ? or am I miss interoperating a complex subject ?

[jagabo]

2-pass does not give you better quality. It gives you predictable file size.

CRF encoding delivers a know quality but an unknown file size. 2-pass bitrate based encoding gives you a know file size but unknown quality. When the file size is equal the picture quality is equal.