FFmpeg's Bitrate Tolerance Option...

[raymng]

I am using FFCoder.
In "Rate Control" -> "Bitrate Tolerance" is set to '1.0'

What does it mean?
I checked the FFmpeg docs, it explains this is "in bits", default=4000k, so 1.0 seems not reasonable here... anybody know?

‘-bt tolerance’
Set video bitrate tolerance (in bits, default 4000k). Has a minimum value of: (target_bitrate/target_framerate). In 1-pass mode, bitrate tolerance specifies how far ratecontrol is willing to deviate from the target average bitrate value. This is not related to min/max bitrate. Lowering tolerance too much has an adverse effect on quality.


By the way, for "AAC" audio codec, the "MPEG Version" can be set to "MPEG-4" or "MPEG-2", what is the corresponding FFmpeg's option??


Thanks!!

[raymng]

Anybody knows??