Device capture/BlackMagic Decklink Capture
For capturing external live video sources, Composer provides a BlackMagic Decklink Capture input.
Blackmagic Decklink Capture v3 - Supports both Windows and Linux OS. Support for multiple Decklink capture cards.
Note!
Starting with Composer R1 2025, the framerate of the cameras must match the framerate of your Composer project.
.png)
Input channel - Selected input channel
Device name - The name of the selected device
Start playing on startup - Check this option to enable capture at application launch. For autostart of inputs, the Autostart inputs options also must be activated on the application level (See the chapter Runtime Performance)
Capture is genlocked to sync source - When enabled, this option tells Composer that the Decklink input is synchronized to an external genlock signal. In this mode, frame duplication and frame skipping are considered impossible, which allows Composer to optimize capture performance by reducing internal buffering.
Keep last frame on lost input - If the DeckLink capture loses the video signal, the last captured frame will be displayed as a still image until the capture resumes.
Use host pinned memory - Used pinned memory will speed up the capture performance.
Commands:
Start capture - Starts the capture
Stop capture - Stops capture
Pause/Unpause - Pause/Unpause capture
Playback state - Current playback state
Performance and properties:
Width - captured video width (pixels)
Height - captured video height (pixels)
# captured frames - The total number of captured frames
# frames played back - Current played frames
Last capture event - Displays the log message of the most recent event.
Render Tuning:
Invisible (Do not render) - Disables rendering. When enabled:
The input will not produce any visible output in the scene.
It can still be used for programmatic control, automation, or audio routing if applicable.
Useful for preparing or testing sources without displaying them live
Do not render input - Disables internal rendering, which can help reduce performance load in some cases.
Render Options - These options, together with
Render Tuning(see Performance and Options), help optimize performance by letting Composer automatically decide whether the input should be rendered.When your project’s
Render Tuningoption is active, Composer manages each input’s rendering automatically for best performance.These options allow you to override that behavior and manually decide if this input should be rendered or excluded from the scene.
Render Tuning vs Render Options:
Render Tuning works at the project level (see Performance and Options), automatically managing which inputs are rendered across all Scenes for optimal performance.
Render Options work at the input level, letting you manually override or fine-tune how a specific input behaves within Composer’s automatic rendering process.
Invisible (do not render in scene) - The input will not produce any visible output in the scene, regardless of whether Render Tuning is enabled at the project level.
Do not render input
Let Composer decide (default) – Composer automatically decides whether the input should be rendered, based on the active Scene and if Render Tuning is enabled.
Manual configuration – Allows you to manually control rendering behavior using the Render switch (see below).
Render - A toggle switch available only when Manual configuration is selected.
Audio - Configure metering, gain, pan, auxiliary sends, mute/solo, routing, and audio channel remapping for this input. See Audio options for more information.
Optional TAGS (space separated)
TAGS - Add a "tag" that can be used in the input smart search function. It is possible to add several tags by separating them with a SPACE character.
* Debug properties. Only visible if 'Show Debug Properties' is enabled in Settings.
Product Compatibility
The following capture cards are currently supported:
BlackMagicDesign Decklink Duo 2
BlackMagicDesign Decklink Quad 2
BlackMagicDesign DeckLink Quad HDMI Recorder (Capture v3 and later)
BlackMagicDesign DeckLink 8K (Capture v3 and later)
BlacMagicDesign Mini Recorder (Capture v3 and later)
Other Decklink versions might work but are not tested or officially supported.
Using multiple capture cards is only supported by the input "Blackmagic Decklink Capture v3" and later.
The two alternatives Blackmagic Decklink Capture v2, Blackmagic Decklink Capture (Windows Only) have been deprecated. However, if you have old projects using these versions of the Decklink input, they will still work and appear in the list of added inputs. We recommend upgrading them to Blackmagic Decklink Capture version 3.
Recommendation!
Using too many Blackmagic Decklink inputs simultaneously can impact the performance of Composer.
Hint!
If you are uncertain about the incoming video format, use the Blackmagic Media Express to detect the video format.
Note!
When using two DeckLink cards of the same type, the cards may be mixed up when restarting the server. To prevent this, use the Label in Desktop Video Settings to name the connectors
For more information and driver updates, please visit https://www.blackmagicdesign.com/support/.