How to Specify Extra Encoder Parameters
It is possible to override or add new encoder parameters using the syntax &ex:key:value. It is definitely NOT recommended for everyone to use this functionality – in the matter of fact, unless you are very technical and have a very good reason to fiddle with this (and you probably do not) then leave the settings alone. (NOTE: We do not provide support assistance for extra encoder parameters)
For x264:
Most parameters supported by the x264 encoder can be found here:
X264 Settings
Simply apply the &ex: syntax instead of — syntax.
For example, “&ex:profile:main” will apply main profile restrictions. “&ex:profile:main&ex:tune:animation” will add tuning for animation content.
Not all x264 options may be supported and please note that any settings you make will override settings from the GUI. So for example if you set “&ex:keyint:60” then you will have a max GOP interval of 60 frames no matter what setting you may have set in the GUI.
For Intel Quick Sync:
What follows are the parameters that we currently support for Quick Sync. Take note that some parameters behave differently or are ignored depending on the Rate Control Method set.
H264 Profile
Param Name: profile
Values:
66 – Baseline
77 – Main
88 – Extended
100 – High
Example: &ex:profile:100
GOP Pic Size (Key Frame Interval)
Param Name: goppicsize
Usage: The number of frames in a group of pictures which also indicates how often a key frame is inserted.
Example: &ex:goppicsize:120
Rate Control Method
Param Name: rc_method
Values:
1 – Constant Bitrate (CBR)
2 – Variable Bitrate (VBR)
3 – Constant Quality Parameter (CQP)
Example: &ex:rc_method:3
Target Kbps
Param Name: targetkbps
Usage:
In CBR – The bitrate used
In VBR – The target bitrate
Example: &ex:targetkbps:3000
Max Kbps
Param Name: maxkbps
Usage:
In VBR: The max bitrate allowed
Constant Quality Parameter Settings
Usage: Only for CQP
Param Names:
qpi – target quality for i-frames
qpp – target quality for p-frames
qpb – target quality for b-frames
Usage:
Should normally be set to have the same values for simplicity. Value provided will approximate the quality of x264’s crf setting but with a bigger file size.
Example: &ex:qpi:23&ex:qpp:23&ex:qpb:23