Project: /_project.yaml Book: /_book.yaml
Defined in fuchsia.media.audio/gain_control.fidl
Enables control and monitoring of audio gain. This interface is typically a tear-off of other interfaces. For example, fuchsia.media.audio.Renderer has a BindGainControl method that binds to a gain control that controls gain for the renderer.
Sets the gain in decibels.
Smoothly changes gain from its current value to specified value, over the specified duration (in milliseconds). If ‘duration_ns’ is 0, gain changes immediately. Otherwise, gain changes only while the stream is running.
Any active or pending ramp is cancelled by subsequent call to SetGain.
There can be at most 1 active ramp at any time. Any active or pending ramp is replaced by a later call to SetGainWithRamp (even if duration is 0). In this case gain would ramps directly from its most recent (mid-ramp) value to the newly-specified one, over the new duration, using the new easing.
Usage example (using time in seconds): Time 0 SetGainWithRamp(MUTED_GAIN_DB, 0, SCALE_LINEAR) // Ramp 1 SetGainWithRamp(0.0f, ZX_SEC(4), SCALE_LINEAR) // Ramp 2 Time 3 PlayNoReply(kNoTimestamp, any_media_time) Time 4 PauseNoReply() Time 7 PlayNoReply(kNoTimestamp, any_media_time) Time 8 SetGainWithRamp(MUTED_GAIN_DB, ZX_SEC(1), SCALE_LINEAR) // Ramp 3
Time 0: Ramp 1 completes immediately, changing the gain to MUTED_GAIN_DB. Ramp 2 is pending, since we are not in playback. Time 3, Ramp 2 begins ramping from MUTED_GAIN_DB to 0 dB (scale 0.0=>1.0). Time 4: Ramp 2 pauses (3s remain). Per SCALE_LINEAR, scale is approx. 0.25. Time 7: Ramp 2 resumes from most recent value toward the target. Time 8: Ramp 3 replaces Ramp 2 and starts from current scale (approx 0.5). Time 9: Ramp 3 completes; current scale value is now 0.0 (MUTED_GAIN_DB).
Sets the mute value. Ramping and mute are fully independent, although they both affect the scaling that is applied.
Notifies the client of changes in the current gain/mute values.
Defined in fuchsia.media.audio/volume_control.fidl
A protocol for controlling volume.
Sets the volume of the audio element to the given value in [0.0, 1.0]. If the value is provided is outside of [0.0, 1.0], the value is clamped before application.
Sets whether the controlled element is muted. Mute is not the same as setting volume to 0.0; volume will persist for the duration of a mute. If volume was 0.5 before mute, volume will resume at 0.5 following unmute.
Emitted when the volume or mute state of the audio element changes.
Acknowledges receipt of a volume or mute change event. Clients must acknowledge receipt to continue receiving events.
Defined in fuchsia.media.audio/gain_control.fidl
Enables control and monitoring of audio gain. This interface is typically a tear-off of other interfaces. For example, fuchsia.media.audio.Renderer has a BindGainControl method that binds to a gain control that controls gain for the renderer.
Sets the gain in decibels.
Smoothly changes gain from its current value to specified value, over the specified duration (in milliseconds). If ‘duration_ns’ is 0, gain changes immediately. Otherwise, gain changes only while the stream is running.
Any active or pending ramp is cancelled by subsequent call to SetGain.
There can be at most 1 active ramp at any time. Any active or pending ramp is replaced by a later call to SetGainWithRamp (even if duration is 0). In this case gain would ramps directly from its most recent (mid-ramp) value to the newly-specified one, over the new duration, using the new easing.
Usage example (using time in seconds): Time 0 SetGainWithRamp(MUTED_GAIN_DB, 0, SCALE_LINEAR) // Ramp 1 SetGainWithRamp(0.0f, ZX_SEC(4), SCALE_LINEAR) // Ramp 2 Time 3 PlayNoReply(kNoTimestamp, any_media_time) Time 4 PauseNoReply() Time 7 PlayNoReply(kNoTimestamp, any_media_time) Time 8 SetGainWithRamp(MUTED_GAIN_DB, ZX_SEC(1), SCALE_LINEAR) // Ramp 3
Time 0: Ramp 1 completes immediately, changing the gain to MUTED_GAIN_DB. Ramp 2 is pending, since we are not in playback. Time 3, Ramp 2 begins ramping from MUTED_GAIN_DB to 0 dB (scale 0.0=>1.0). Time 4: Ramp 2 pauses (3s remain). Per SCALE_LINEAR, scale is approx. 0.25. Time 7: Ramp 2 resumes from most recent value toward the target. Time 8: Ramp 3 replaces Ramp 2 and starts from current scale (approx 0.5). Time 9: Ramp 3 completes; current scale value is now 0.0 (MUTED_GAIN_DB).
Sets the mute value. Ramping and mute are fully independent, although they both affect the scaling that is applied.
Notifies the client of changes in the current gain/mute values.
Defined in fuchsia.media.audio/volume_control.fidl
A protocol for controlling volume.
Sets the volume of the audio element to the given value in [0.0, 1.0]. If the value is provided is outside of [0.0, 1.0], the value is clamped before application.
Sets whether the controlled element is muted. Mute is not the same as setting volume to 0.0; volume will persist for the duration of a mute. If volume was 0.5 before mute, volume will resume at 0.5 following unmute.
Emitted when the volume or mute state of the audio element changes.
Acknowledges receipt of a volume or mute change event. Clients must acknowledge receipt to continue receiving events.
Type: uint16
Defined in fuchsia.media.audio/gain_control.fidl
Enumerates gain control ramp types.
Type: uint16
Defined in fuchsia.media.audio/gain_control.fidl
Enumerates gain control ramp types.