[vlc-devel] commit: x264: use ABR-mode if user specifies bitrate (Ilkka Ollakka )
git version control
git at videolan.org
Thu Sep 17 16:15:47 CEST 2009
vlc | branch: 1.0-bugfix | Ilkka Ollakka <ileoo at videolan.org> | Tue Jul 28 13:43:57 2009 +0300| [0eaed066d7cb24ead9380dbbea72c7ca700572e7] | committer: Ilkka Ollakka
x264: use ABR-mode if user specifies bitrate
Also set vbv-bufsize if user didn't specify them.
bufsize is bitrate * seconds between keyframes instead of earlier
2*bitrate. Recommended by Dark_Shikari
So now you can stream for mobiles with following:
sout="#transcode{deinterlace,acodec=mp4a,vcodec=h264,width=320,height=180,venc=x264{no-cabac,bframes=0,ref=3,level=12,keyint=50},vb=180,ab=64,channels=2}...
tested with rtp-output and G1 android. Produces quite stable near cbr
stream.
And file-encoding should be ok with defaults (without any
venc=x264-settings or bitrates), if not targeted to
handhelds/streaming.
(cherry-picked from 9543a6abc6b57f5b1f9f49755daf8ed711836b29)
Also default qp=-1 so CQP-mode is only used when user defines qp-value
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=0eaed066d7cb24ead9380dbbea72c7ca700572e7
---
modules/codec/x264.c | 66 +++++++++++++++++++++++++++++++++++++++++--------
1 files changed, 55 insertions(+), 11 deletions(-)
diff --git a/modules/codec/x264.c b/modules/codec/x264.c
index dd533cd..ef039ef 100644
--- a/modules/codec/x264.c
+++ b/modules/codec/x264.c
@@ -492,12 +492,12 @@ vlc_module_begin ()
/* Ratecontrol */
- add_integer( SOUT_CFG_PREFIX "qp", 26, NULL, QP_TEXT, QP_LONGTEXT,
+ add_integer( SOUT_CFG_PREFIX "qp", -1, NULL, QP_TEXT, QP_LONGTEXT,
false )
- change_integer_range( 0, 51 ) /* QP 0 -> lossless encoding */
+ change_integer_range( -1, 51 ) /* QP 0 -> lossless encoding */
#if X264_BUILD >= 37 /* r334 */
- add_integer( SOUT_CFG_PREFIX "crf", 0, NULL, CRF_TEXT,
+ add_integer( SOUT_CFG_PREFIX "crf", 23, NULL, CRF_TEXT,
CRF_LONGTEXT, false )
change_integer_range( 0, 51 )
#endif
@@ -814,8 +814,39 @@ static int Open ( vlc_object_t *p_this )
p_sys->param.i_height = p_sys->param.i_height >> 4 << 4;
#endif
- /* average bitrate specified by transcode vb */
- p_sys->param.rc.i_bitrate = p_enc->fmt_out.i_bitrate / 1000;
+
+ var_Get( p_enc, SOUT_CFG_PREFIX "qcomp", &val );
+ p_sys->param.rc.f_qcompress = val.f_float;
+
+ /* transcode-default bitrate is 0,
+ * set more to ABR if user specifies bitrate */
+ if( p_enc->fmt_out.i_bitrate > 0 )
+ {
+ p_sys->param.rc.i_bitrate = p_enc->fmt_out.i_bitrate / 1000;
+#if X264_BUILD < 48
+ /* cbr = 1 overrides qp or crf and sets an average bitrate
+ but maxrate = average bitrate is needed for "real" CBR */
+ p_sys->param.rc.b_cbr=1;
+#endif
+ p_sys->param.rc.i_rc_method = X264_RC_ABR;
+ }
+ else /* Set default to CRF */
+ {
+#if X264_BUILD >= 37
+ var_Get( p_enc, SOUT_CFG_PREFIX "crf", &val );
+ if( val.i_int > 0 && val.i_int <= 51 )
+ {
+# if X264_BUILD >= 54
+ p_sys->param.rc.f_rf_constant = val.i_int;
+# else
+ p_sys->param.rc.i_rf_constant = val.i_int;
+# endif
+# if X264_BUILD >= 48
+ p_sys->param.rc.i_rc_method = X264_RC_CRF;
+# endif
+ }
+#endif
+ }
var_Get( p_enc, SOUT_CFG_PREFIX "qpstep", &val );
if( val.i_int >= 0 && val.i_int <= 51 ) p_sys->param.rc.i_qp_step = val.i_int;
@@ -866,12 +897,6 @@ static int Open ( vlc_object_t *p_this )
var_Get( p_enc, SOUT_CFG_PREFIX "vbv-bufsize", &val );
p_sys->param.rc.i_vbv_buffer_size = val.i_int;
- /* x264 vbv-bufsize = 0 (default). if not provided set period
- in seconds for local maximum bitrate (cache/bufsize) based
- on average bitrate. */
- if( !val.i_int )
- p_sys->param.rc.i_vbv_buffer_size = p_sys->param.rc.i_bitrate * 2;
-
/* max bitrate = average bitrate -> CBR */
var_Get( p_enc, SOUT_CFG_PREFIX "vbv-maxrate", &val );
#if X264_BUILD >= 48
@@ -1237,6 +1262,25 @@ static int Open ( vlc_object_t *p_this )
p_sys->param.i_fps_den = p_enc->fmt_in.video.i_frame_rate_base;
}
+ /* x264 vbv-bufsize = 0 (default). if not provided set period
+ in seconds for local maximum bitrate (cache/bufsize) based
+ on average bitrate when use has told bitrate.
+ vbv-buffer size is set to bitrate * secods between keyframes */
+ if( !p_sys->param.rc.i_vbv_buffer_size &&
+ p_sys->param.rc.i_rc_method == X264_RC_ABR &&
+ p_sys->param.i_fps_num )
+ {
+ p_sys->param.rc.i_vbv_buffer_size = p_sys->param.rc.i_bitrate *
+ p_sys->param.i_fps_den;
+#if X264_BUILD >= 0x000e
+ p_sys->param.rc.i_vbv_buffer_size *= p_sys->param.i_keyint_max;
+#else
+ p_sys->param.rc.i_vbv_buffer_size *= p_sys->param.i_idrframe;
+#endif
+ p_sys->param.rc.i_vbv_buffer_size /= p_sys->param.i_fps_num;
+ }
+
+
unsigned i_cpu = vlc_CPU();
if( !(i_cpu & CPU_CAPABILITY_MMX) )
{
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