[openqwaq] r213 committed - Tweak quality setting to avoid blowing past session-recording bitrate ...

[open...@googlecode.com]

Revision: 213
Author: sch...@gmail.com
Date: Sun Feb 5 12:59:51 2012
Log: Tweak quality setting to avoid blowing past session-recording
bitrate limits.
http://code.google.com/p/openqwaq/source/detail?r=213

Modified:

/trunk/qwaqvm/platforms/Cross/plugins/QVideoCodecPluginFree/qVideoEncoder.cpp

=======================================
---
/trunk/qwaqvm/platforms/Cross/plugins/QVideoCodecPluginFree/qVideoEncoder.cpp
Fri Feb 3 00:35:51 2012
+++
/trunk/qwaqvm/platforms/Cross/plugins/QVideoCodecPluginFree/qVideoEncoder.cpp
Sun Feb 5 12:59:51 2012
@@ -128,14 +128,19 @@
// to make it work.
param.b_vfr_input = 0;

+ // Don't believe that we pay attention to this... see comments below
+ // about quality- vs. bitrated based targets.
param.rc.i_bitrate = vargs->bitRate;

// We used to use these, but they don't seem to be needed???
// param.rc.i_vbv_max_bitrate = vargs->bitRate;
// param.rc.i_vbv_buffer_size = 30;

- // quality target
- param.rc.f_rf_constant = 20;
+ // Quality. We use a quality-based target rather than a bitrate
+ // target, so it's a bit tricky to choose a value that gives the
+ // desired bitrate. This setting has been empirically selected
+ // to look good enough, and be low-bitrate enough.
+ param.rc.f_rf_constant = 25;
param.rc.i_rc_method = X264_RC_CRF;

// Yeah, I know that "zero latency" isn't a "profile" per-se...