ParameterRateControl
From Diracvideo
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[edit] Constant Noise Threshold (0)
This approximates constant quality, although not very well. The noise threshold is controlled by the parameter "noise_threshold". Typical useful values are in the range of 20 to 30.
[edit] Constant Bit Rate (1)
This is the best developed and tested rate control mechanism. When used, the encoder will create a constant bit rate stream. The bit rate is specified by the "bitrate" parameter. The buffer size is 3*bitrate, and is currently not adjustable.
[edit] Low Delay (2)
Low delay rate control causes the encoder to encode pictures using the low-delay syntax of Dirac-1.0. This is only useful for very high bit rate mezzanine encoding.
[edit] Lossless (3)
Lossless rate control causes the encoder to encode losslessly.
[edit] Constant Lambda (4)
Not API stable -- may change in functionality
Used for testing. Constant lambda uses the same rate-distortion techniques as constant bit rate, but doesn't vary the lambda value from picture to picture to control the bit rate. Thus, you get a variable bit rate stream with some of the features of CBR. Lambda is controlled by magic_lambda.
Added in 1.0.2
[edit] Constant Error (5)
Not API stable -- may change in functionality
Used for testing. Encodes a VBR stream that has a nearly constant PSNR value. The expected PSNR is calculated before encoding each picture, so the actual PSNR value of each picture varies somewhat. Target PSNR value is controlled using noise_threshold.
Added in 1.0.2
