Changes between Version 61 and Version 62 of Encode/H.264

Timestamp:

Jul 7, 2017, 10:09:17 AM (9 years ago)

Author:

su

Comment:

I encoded a file by specifying the -maxrate to 24M, but the result is around 32M. It seems only two-pass strictly control the max rate

Encode/H.264

@@ -148 +148 @@
 === Constained encoding (VBV / maximum bit rate) ===
 
-You can also also use `-crf` or `-b:v` with a maximum bit rate by specifying both  `-maxrate` and `-bufsize`:
+You can also use `-crf` or `-b:v` with a maximum bit rate by specifying both  `-maxrate` and `-bufsize`:
 
 {{{
@@ -154 +154 @@
 }}}
 
-This will effectively "target" `-crf 23`, but if the output were to exceed 1 MBit/s, the encoder would increase the CRF to prevent bitrate spikes.
+This will effectively "target" `-crf 23`, but if the output were to exceed 1 MBit/s, the encoder would increase the CRF to prevent bitrate spikes. However, be aware that `libx264` does not strictly control the maximum bit rate as you specified (the maximum bit rate may be well over 1M for the above file). To reach a perfect maximum bit rate, use two-pass.
 
 In another example, instead of using constant quality (CRF) as a target, the average bitrate is set. A two-pass approach is preferred here: