2.5.34 IDeckLinkEncoderInput Interface

The IDeckLinkEncoderInput interface allows an application to capture an encoded video and audio stream from a DeckLink device.

An IDeckLinkEncoderInput interface can be obtained from an IDeckLink interface using QueryInterface. If QueryInterface for an input interface is called on a device which does not support encoded capture, then QueryInterface will fail and return E_NOINTERFACE.

Encoded Video capture operates in a push model with encoded video data delivered to an IDeckLinkEncoderInputCallback interface. Audio capture is optional and can be handled by using the same callback object.

Related Interfaces

Interface

Interface ID

Description

IDeckLink

IID_IDeckLink

An IDeckLinkEncoderInput object interface may be obtained from IDeckLink using QueryInterface

IDeckLinkDisplayMode

IID_IDeckLinkDisplayMode

IDeckLinkEncoderInput::GetDisplayMode() outputs an IDeckLinkDisplayMode object interface

IDeckLinkDisplayModeIterator

IID_IDeckLinkDisplayModeIterator

IDeckLinkEncoderInput::GetDisplayModeIterator() outputs an IDeckLinkDisplayModeIterator object interface

IDeckLinkEncoderInputCallback

IID_IDeckLinkEncoderInputCallback

An IDeckLinkEncoderInputCallback object interface is registered with IDeckLinkEncoderInput::SetCallback()

IDeckLinkEncoderConfiguration

IID_IDeckLinkEncoderConfiguration

An IDeckLinkEncoderConfiguration object interface may be obtained from IDeckLinkEncoderInput using QueryInterface

2.5.34.1 IDeckLinkEncoderInput::DoesSupportVideoMode method

HRESULT IDeckLinkEncoderInput::DoesSupportVideoMode(BMDVideoConnection connection, BMDDisplayMode requestedMode, BMDPixelFormat requestedCodec, uint32_t requestedCodecProfile, BMDSupportedVideoModeFlags flags, Boolean *supported);

The DoesSupportVideoMode method indicates whether a given display mode is supported on encoder input.

Parameters:
Return values:

  • E_INVALIDARG – Either parameter requestedMode has an invalid value or parameter supported variable is NULL.

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.2 IDeckLinkEncoderInput::GetDisplayMode method

HRESULT IDeckLinkEncoderInput::GetDisplayMode(BMDDisplayMode displayMode, IDeckLinkDisplayMode **resultDisplayMode);

The GetDisplayMode method returns the IDeckLinkDisplayMode interface for an input display mode identifier.

Parameters:

  • displayMode – The display mode ID (See BMDDisplayMode).

  • resultDisplayMode – Pointer to the display mode with matching ID. The object must be released by the caller when no longer required.

Return values:

  • E_INVALIDARG – Either parameter displayMode has an invalid value or parameter resultDisplayMode variable is NULL.

  • E_OUTOFMEMORY – Insufficient memory to create the result display mode object.

  • S_OK – Success

2.5.34.3 IDeckLinkEncoderInput::GetDisplayModeIterator method

HRESULT IDeckLinkEncoderInput::GetDisplayModeIterator(IDeckLinkDisplayModeIterator **iterator);

The GetDisplayModeIterator method returns an iterator which enumerates the available display modes.

Parameters:

iterator – Display mode iterator

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.4 IDeckLinkEncoderInput::EnableVideoInput method

HRESULT IDeckLinkEncoderInput::EnableVideoInput(BMDDisplayMode displayMode, BMDPixelFormat pixelFormat, BMDVideoInputFlags flags);

The EnableVideoInput method configures video input and puts the hardware into encoded video capture mode. Video input (and optionally audio input) is started by calling StartStreams.

Parameters:

  • displayMode – Video mode to capture

  • pixelFormat – Pixel format to capture

  • flags – Capture flags

Return values:

  • E_INVALIDARG – Is returned on invalid mode or video flags

  • E_ACCESSDENIED – Unable to access the hardware or input stream currently active

  • E_OUTOFMEMORY – Unable to create a new frame

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.5 IDeckLinkEncoderInput::DisableVideoInput method

HRESULT IDeckLinkEncoderInput::DisableVideoInput();

The DisableVideoInput method disables the hardware video capture mode.

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.6 IDeckLinkEncoderInput::GetAvailablePacketsCount method

HRESULT IDeckLinkEncoderInput::GetAvailablePacketsCount(uint32_t *availablePacketsCount);

The GetAvailablePacketsCount method provides the number of encoded video packets that are queued to be delivered to the IDeckLinkEncoderInputCallback::VideoPacketArrived() callback.

Parameters:

availablePacketsCount – Number of available encoded packets

Return values:

S_OK – Success

2.5.34.7 IDeckLinkEncoderInput::EnableAudioInput method

HRESULT IDeckLinkEncoderInput::EnableAudioInput(BMDAudioFormat audioFormat, BMDAudioSampleRate sampleRate, BMDAudioSampleType sampleType, uint32_t channelCount);

The EnableAudioInput method configures audio input and puts the hardware into audio capture mode. Encoded audio and video input is started by calling StartStreams.

Parameters:

  • audioFormat – Audio format to encode.

  • sampleRate – Sample rate to capture

  • sampleType – Sample type to capture

  • channelCount – Number of audio channels to capture - only 2, 8 or 16 channel capture is supported.

Return values:

  • E_INVALIDARG – Invalid audio format or number of channels requested.

  • E_ACCESSDENIED – Unable to access the hardware or input stream currently active.

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.8 IDeckLinkEncoderInput::DisableAudioInput method

HRESULT IDeckLinkEncoderInput::DisableAudioInput();

The DisableAudioInput method disables the hardware audio capture mode.

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.9 IDeckLinkEncoderInput::GetAvailableAudioSampleFrameCount method

HRESULT IDeckLinkEncoderInput::GetAvailableAudioSampleFrameCount(uint32_t *availableSampleFrameCount);

The GetAvailableAudioSampleFrameCount method returns the number of audio sample frames currently buffered.

Parameters:

availableSampleFrameCount – The number of buffered audio frames currently available.

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.10 IDeckLinkEncoderInput::StartStreams method

HRESULT IDeckLinkEncoderInput::StartStreams();

The StartStreams method starts encoded video and audio capture as configured with EnableVideoInput and optionally EnableAudioInput.

Return values:

  • E_ACCESSDENIED – Input stream is already running.

  • E_UNEXPECTED – Neither video or audio inputs have been enabled.

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.11 IDeckLinkEncoderInput::StopStreams method

HRESULT IDeckLinkEncoderInput::StopStreams();

The StopStreams method stops encoded video and audio capture.

Return values:

  • E_ACCESSDENIED – Input stream already stopped.

  • S_OK – Success

2.5.34.12 IDeckLinkEncoderInput::PauseStreams method

HRESULT IDeckLinkEncoderInput::PauseStreams();

The PauseStreams method pauses encoded video and audio capture. Capture time continues while the streams are paused but no video or audio will be captured.

Paused capture may be resumed by calling PauseStreams again. Capture may also be resumed by calling StartStreams but capture time will be reset.

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.13 IDeckLinkEncoderInput::FlushStreams method

HRESULT IDeckLinkEncoderInput::FlushStreams();

The FlushStreams method removes any buffered video and audio packets.

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.14 IDeckLinkEncoderInput::SetCallback method

HRESULT IDeckLinkEncoderInput::SetCallback(IDeckLinkEncoderInputCallback *theCallback);

The SetCallback method configures a callback which will be called as new encoded video, and audio packets become available. Encoder capture is started with StartStreams, stopped with StopStreams and may be paused with PauseStreams.

Parameters:

theCallback – Callback object implementing the IDeckLinkEncoderInputCallback interface

Return values:

  • E_FAIL – Failure

  • S_OK – Success

2.5.34.15 IDeckLinkEncoderInput::GetHardwareReferenceClock method

HRESULT IDeckLinkEncoderInput::GetHardwareReferenceClock(BMDTimeScale desiredTimeScale, BMDTimeValue *hardwareTime, BMDTimeValue *timeInFrame, BMDTimeValue *ticksPerFrame);

The GetHardwareReferenceClock method returns a clock that is locked to the system clock.

The absolute values returned by this method are meaningless, however the relative differences between subsequent calls can be used to determine elapsed time.

This method can be called while video input is enabled (see IDeckLinkEncoderInput::EnableVideoInput() for details).

Parameters:

  • desiredTimeScale – Desired time scale

  • hardwareTime – Hardware reference time (in units of desiredTimeScale)

  • timeInFrame – Time elapsed since the start of the frame (in units of desiredTimeScale)

  • ticksPerFrame – Number of ticks for a frame (in units of desiredTimeScale)

Return values:

  • E_FAIL – Failure

  • S_OK – Success