IVSBroadcastMixer

Objective-C

@interface IVSBroadcastMixer : NSObject

Swift

class IVSBroadcastMixer : NSObject

The mixer determines the final on-screen and in-ear state for visual elements and audio.

An element is represented by an IVSMixerSlotConfiguration that has a number of associated parameters to place an image stream spatially and set the gain of an audio stream from a device.

Each slot can be bound to a single image device (such as a camera) and a single audio device (such as a microphone).

  • Returns the currently added slots.

    Note

    for slots that are performing an animated transition, this will return the state of the slot before the transition.

    Declaration

    Objective-C

    - (nonnull NSArray<IVSMixerSlotConfiguration *> *)slots;

    Swift

    func slots() -> [IVSMixerSlotConfiguration]

  • Transition a slot to a new state.

    Multiple concurrent transitions are not supported on the same slot. If you initiate a second transition before the first is finished, the transition will start over from the original slot state and transition to the new state as if the first transition had never been made.

    If there are no devices to to the slot being animated, the duration parameter will be ignored and the slot will be updated immediately.

    Declaration

    Objective-C

    - (BOOL)transitionSlotWithName:(nonnull NSString *)slotName
                       toState:(nonnull IVSMixerSlotConfiguration *)nextState
                      duration:(NSTimeInterval)duration
                    onComplete:(nullable void (^)(void))onComplete;

    Swift

    func transitionSlot(withName slotName: String, toState nextState: IVSMixerSlotConfiguration, duration: TimeInterval, onComplete: (() -> Void)? = nil) -> Bool

    Parameters

    slotName

    The target slot’s name
    nextState

    The new state for the slot
    duration

    The amount of time to animate the transition for
    onComplete

    An optional callback that will be called when the animation has completed

    Return Value

    true if a matching slot was found and updated, false otherwise

  • Add a new slot to the mixer configuration

    Declaration

    Objective-C

    - (BOOL)addSlot:(nonnull IVSMixerSlotConfiguration *)slot;

    Swift

    func addSlot(_ slot: IVSMixerSlotConfiguration) -> Bool

    Parameters

    slot

    The slot configuration to be added

    Return Value

    Success

  • Remove a slot from the mixer configuration

    Declaration

    Objective-C

    - (BOOL)removeSlotWithName:(nonnull NSString *)slotName;

    Swift

    func removeSlot(withName slotName: String) -> Bool

    Parameters

    slotName

    The slot to be removed

    Return Value

    Success

  • Bind a device’s output to the first mixer slot that isn’t already bound for this device’s stream type, and matches the device type.

    Declaration

    Objective-C

    - (nullable NSString *)bindDeviceToFirstCompatibleSlot:
    (nonnull id<IVSDevice>)device;

    Parameters

    device

    The device to bind to the mixer

    Return Value

    The name of the slot the device was bound to. nil if no compatible slot was found.

  • Bind a device’s output to a mixer slot (specified in the mixer configuration). A common source of failure for this API is if a slot does not exist matching the provided slotName. Use slots to verify the slot exists.

    Declaration

    Objective-C

    - (BOOL)bindDevice:(nonnull id<IVSDevice>)device
    toSlotWithName:(nonnull NSString *)slotName;

    Parameters

    device

    The device to bind to the mixer
    slotName

    The target slot’s name

    Return Value

    true if the bind was successful.

  • Unbind a device from the mixer.

    Declaration

    Objective-C

    - (BOOL)unbindDevice:(nonnull id<IVSDevice>)device;

    Parameters

    device

    The device to unbind

    Return Value

    true if a binding was found and removed.

  • Get a device’s current binding, if it is bound.

    Declaration

    Objective-C

    - (nullable NSString *)bindingForDevice:(nonnull id<IVSDevice>)device;

    Parameters

    device

    The device to query

    Return Value

    A slot name if it is bound, otherwise nil.

  • Get a slot’s current bindings, if any are bound.

    Declaration

    Objective-C

    - (nullable NSArray<NSString *> *)devicesBoundToSlotWithName:
    (nonnull NSString *)slotName;

    Swift

    func devicesBoundToSlot(withName slotName: String) -> [String]?

    Parameters

    slotName

    The name of the slot to query

    Return Value

    A list of device URNs bound to the slot. This will be empty if the slot exists but no devices are bound, but nil if no matching slot exists.