title: Mix
media types:
Audio
description: Mix two audio tracks.
version: 5
creator: Dan Dennedy
copyright: Meltytech, LLC
license: LGPLv2.1
title: Start
description:
The mix level to apply to the second frame. -1 causes an automatic linear crossfade from 0 to 1. -2 causes an automatic constant-power (equal-power) crossfade from 0 to 1.
type: float
readonly: no
required: no
title: End
description:
The ending value of the mix level. Mix level will be interpolated from start to end over the in-out range.
type: float
readonly: no
required: no
title: Reverse
description:
Set to 1 to reverse the direction of the mix.
type: boolean
readonly: no
required: no
default: 0
widget: checkbox
title: Use an alternative mixing algorithm
description:
Mix using a low pass filter to prevent affecting audio levels. However, this may introduce slight artifacts. This is incompatible with start < 0.
type: boolean
readonly: no
required: no
default: 0
title: Mix by simply adding samples
description:
The default mixing algorithm halves the sample values before adding them to absolutely prevent clipping. However, that affects levels. This algorithm simply adds samples and may clip. In many real world scenarios, the signals being mixed typically have headroom in their level and are rarely correlated and thus often will not clip. Also, one can reduce the gain and add a limiter on the mixed output prior to integer quantization to prevent clipping. This mode is incompatible with start < 0.
type: boolean
readonly: no
required: no
default: 0
title: Duck Threshold
description:
Enables ducking when non-zero. If the RMS level of frame A exceeds this dBFS threshold, frame B is attenuated before mixing. When this is non- zero, the sum and combine mix modes are ignored.
type: float
readonly: no
required: no
default: 0
unit: dB
widget: slider
title: Duck Attenuation
description:
The minimum attenuation, in dBFS, applied to frame B while ducking.
type: float
readonly: no
required: no
default: -12
unit: dB
widget: slider
title: Duck Level
description:
Reports the current gain reduction, in dB, being applied to frame B.
type: float
readonly: yes
required: no
default: 0
unit: dB
widget: spinner
title: Duck Fade In
description:
The fade-in time, in milliseconds, used when restoring frame B.
type: float
readonly: no
required: no
minimum: 0
maximum: 5000
default: 1500
unit: ms
widget: spinner
title: Duck Fade Out
description:
The fade-out time, in milliseconds, used when reducing frame B.
type: float
readonly: no
required: no
minimum: 0
maximum: 5000
default: 250
unit: ms
widget: spinner
title: Frame Property Prefix
description:
When non-empty, the duck level is also written to a frame property named "<prefix>duck_level" on frame A so that it can be read back once that frame is actually presented. When empty, no frame property is set.
type: string
readonly: no
required: no
Subscribe to News via RSS.