Quick Sync Two Pass

[roberto188]

I have an i5 2500k which I've been using Handbrake to encode some stuff. It's very fast, 160+ fps and quality that is very nice as far as I can tell. I do however love how 2 pass encoding provides superior quality and size. Is there any encoder that supports Sandy Bridge Quick Sync with 2 pass encoding?

[stonesfan99]

Intel Quick Sync is the encoder. If you're talking about a program that supports this, I would stick to Handbrake. I would also advise spending the money and upgrading to something like the AMD Ryzen 7 1700X or 1800X 8-core. These will give you 8C/16T and CPU encoding (x264) will produce superior quality to GPU encoding (Intel Quick Sync).

[jagabo]

I don't think QS supports 2-pass encoding. Certainly not in Handbrake.

2-pass bitrate based encoding doesn't deliver better quality than, single pass rate factor based encoding. With bitrate based encoding you get a know file size, but unknown quality. With rate factor based encoding you get a know quality, but unknown file size. When the sizes match the quality also matches. Use 2-pass encoding when you need a specific file size (to put a movie on a CD, for example). Otherwise use rate factor based encoding.

[roberto188]

Quicksync certainly does support 2-two encoding. None the less it there another gui based program that provides a bit more options for quicksync encoding? Hanbrake essentially only allows "quick" or "balanced" settings.

[jagabo]

Quicksync certainly does support 2-two encoding.

This document is pretty old but an Intel representative states QS doesn't support 2-pass encoding:
https://software.intel.com/en-us/forums/intel-media-sdk/topic/311693

The Intel Media SDK does not support "2 pass encoding" in the sense that it does not examining the entire stream twice. When the AVBR encode mode is used the encoding algorithm tries to achieve some of the same goals achieved with typical 2 pass encoding (which is why I believe some applications call it "2 pass",

That "fake" 2-pass encoding is really just a lookahead buffer (up to 60 frames).

QS h.264 encoding has improved since then (mostly at the Haswell generation, beyond Haswell attention has gone to h.265 and VP8) so real 2-pass encoding might be available with newer versions (I haven't seen any authoritative claims). But you're using a i5 2500K so that probably won't apply to you.

Handbrake's Quick Sync options:
https://handbrake.fr/docs/en/latest/technical/video-qsv-options.html

Handbrake's take on 2-pass vs. constant quality encoding:
https://handbrake.fr/docs/en/latest/technical/video-cq-vs-abr.html