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View Full Version : Can CCE do controlled VBR?


Skelsgard
28th January 2006, 21:30
As I can with H264 and did with DivX, I control the bitrate of encoding with too basic parameters: quantizers and bitrate. At single-pass with fixed quantizer, these codecs enforce the q option over the bitrate option. Therefore if a scene is to be compressed (let`s say in DivX) with a q=2 and bitrate 200 kbps, it will only go above the BR when the q can no t be maintained with the BR. Therefore an entire movie can be compressed with low bitrate while those scenes that requiere high bitrate will get it since the q=2 forces the BR to go up. (I`m trying to explain this as good as posible so nobody comes telling me that "VBR can be used to compress, I don`t understand what`s the question").
Can CCE allow to select the max quantizer and bitrate and apply them alltogether (with q ruling over BR) or just can do plain VBR?

Trahald
30th January 2006, 15:18
cce either uses the bitrate or the quantizer factor.. with quantizer factor you can set a max and min bitrate which gives you some worst case predictability (it will be no bigger than 'x').. not generally recommended to use the max bitrate for file sizing because mpeg2 tends to need a generous max bitrate to look good and rather max bitrate setting is there to keep compliancy (dvd or possibly other application)