Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion.

Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules.


Go Back   Doom9's Forum > Video Encoding > MPEG-4 AVC / H.264

Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
Old 15th November 2013, 12:32   #1  |  Link
Registered User
Join Date: Sep 2013
Posts: 38
What is the exactly CBR in x264?

Today I read some material from Internet about rate control of x264 and I learned what is the ABR mode. When only the param --bitrate is set, ABR mode is used. But I am confused about the CBR mode.
At first I think when the params --vbv-maxrate and --vbv-bufsize are set together with --bitrate , the CBR mode is used. Then I see these codes from x264:
  s += sprintf( s, " rc=%s mbtree=%d", p->rc.i_rc_method == X264_RC_ABR ?
                               ( p->rc.b_stat_read ? "2pass" : p->rc.i_vbv_max_bitrate == p->rc.i_bitrate ? "cbr" : "abr" )
                               : p->rc.i_rc_method == X264_RC_CRF ? "crf" : "cqp", p->rc.b_mb_tree );
Apparently, only the situation that vbv-maxrate equals bitrate, it is CBR. When the vbv-maxrate is greater than bitrate, it is still ABR mode. I want to confirm if it is correct.
xkfz007 is offline   Reply With Quote

rate control, x264

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT +1. The time now is 19:58.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.