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CL2 Node Widgets

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Node widgets are the visual boxes in the Project view. They determine what your Conduit Live project actually renders. It's important to understand how node widgets can work together. While it would be possible to create a project which contains only a single node (for example, a Movie Source node would be enough if all you need is video playback), most projects are not so simple and require more functionality which can be achieved by combining multiple nodes to work together.

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Node widget connection types

There are two important types of connections between node widgets. The first is a video stream connection. This is what you’ll use to connect a Movie Source node into a Conduit Effect’s image input, for example. Ports that support this kind of connection are marked with a shiny black dot.

The second type of connection is a value connection, which represents any kind of data that is not a video stream. The Slider Bank node widget has a single value output which provides the slider’s values as a "list". To make these values available to a Conduit Effect node widget, the ports need to be connected accordingly. (When starting a new project in Conduit Live 2, this connection is already made.)

The advantage of separating the Slider Bank and Conduit Effect node widgets is flexibility; you can replace the sliders with something completely else. As an example, there could be a node widget to fetch realtime data from an online source, and another node widget could condense that data into a couple of important numbers. These numbers could then be used instead of the Slider Bank node widget to "drive" the values in a Conduit Effect.

To give you an overview of what's happening in the project, the Project view has a mode for displaying the data types and the current content being passed between node widgets. This is enabled by toggling the checkbox "Show node output values" in the bottom-right corner of the Project window. (It's on by default.)

To convert data into a video stream that can be watched, there is a Convert Value to Video node which will output a video stream that represents the value data. For most types, this is an image containing a text listing of the data. This can be tested easily by connecting a Slider Bank to Convert Value to Video: the result is essentially a printout of the slider values.

Convert Value to Video is smart enough to recognize if its value input is actually an Image object, in which case it will output that image instead of a text listing of the object. (The Image object could be generated by a Script Widget node based on some data loaded from a web server, for example.)

Display

The project contains a single Multi-Display node widget. Any video stream that's connected to this node widget is shown in the Viewer window. If full-screen mode is enabled, the image is also shown there.

The display node provided in Conduit Live 2 is called multi-display because it has four inputs. This allows it to be used to create a layout of up to four video streams on screen. Alpha compositing is supported. This makes it convenient for inserting overlay elements that are always placed at a specific location on-screen, such as subtitles or a TV channel logo -- or simply doing a quick preview of multiple streams composited on top of each other.

Multi-screen output using Matrox GXM

The Multi-Display node widget can also be used with the Matrox DualHead2Go and TripleHead2Go graphics expansion modules. These devices are a practical and easy way of doing multi-display output from a laptop or iMac computer. Conduit Live 2 includes presets for the DualHead/TripleHead monitor layouts, so setting up the multiple displays is a one-click operation.

To configure the display layout, click on the "Setup Screen Layout" button on the Multi-Display node widget.

Video sources

The most common type of input source is Movie/Image Source. This node widget loads a video file, image sequence or still image from disk, and outputs a frame at a specific position.

The node widget has the following playback controls: Play/Pause (single button), Rewind/Frame Forward/Frame Backward.

Note that the playback controls are only effective when the project is in Free Run mode. In Timeline mode, the node's output is determined entirely by the current timeline position. (This behavior makes sense if you think of the node as being a video clip within a timeline in a video editing application: you want it to output the same frame each time a particular position in the timeline is being rendered. For more information about Free Run vs. Timeline mode, see CL2 Project#Free Run and Timeline modes.)

There is also another kind of image input source, the Embedded Image node widget. It only supports still images. Once an image is loaded into Embedded Image, it's stored as part of the project and does not require the original image file anymore.

Another type of input source node widget are generators. These output an image without any external feed. There are two generators included in Conduit Live: Test Pattern outputs a test image which can be chosen from a list of typical patterns such as color bars, gradient color bars and grid. Noise Generator outputs video noise.

Supported file formats

The Movie/Image Source node supports at least the following formats. (Embedded Image supports the same still image formats, but not QuickTime video.)

  • QuickTime RGB, all codecs (with optional alpha)
  • QuickTime "raw YUV"
    This mode offers best quality with pro video codecs and includes 10-bit support; see Pro Pixels Guide for more information.
  • Cineon/DPX image sequences: RGB 8/10/16 bits per channel, YUV 8-bit
    10-bit Cineon/DPX files often use a logarithmic color space; to decode, use the Cineon to Linear node within a Conduit Effect.
  • OpenEXR image sequences: floating point HDR
    Multiple channels are supported; see Pro Pixels Guide for more information.
  • TIFF image sequences: RGB 8/16 bits per channel (with optional alpha)
    CMYK TIFF images are interpreted as RGBA and will look incorrect. A CMYK->RGB conversion can be done using Conduit Effect.
  • PNG, JPEG, GIF, PSD, and other file formats supported by the operating system.

Live Source

The Live Source (QuickTime) node captures live video from any QuickTime-compatible device such as a video capture card, a webcam or a DV/HDV/AVCHD video camera.

It can be set up to record the incoming data to disk. For more information, see CL2 Recording.

Effects

Conduit Effect is the most common type of effect node. The effect that is produced by this node widget is determined by the conduit, that is, an effect setup that you can edit in Conduit Editor. For more information, see CL2 Conduit Editor.

Scripted Effect is a node widget that renders a completely custom effect programmed in JavaScript. There are some examples of how to use this node included in the default templates as part of Conduit Live 2. They are shown in the start-up screen.

Processing Scripted Effect is similar to Scripted Effect except that it is programmed in the Processing language instead of JavaScript.

Capturing video

Rendered Capture writes the incoming video stream to disk. The video is written as an image sequence. You can choose the image format (e.g. DPX or PNG) from the node widget's settings.

Note that Conduit Live also allows the original video stream to be recorded from a camera or other capture device (or indeed multiple devices simultaneously). That is the recommended way to do recording in Conduit Live, because it guarantees that the video is recorded in its original format and includes any audio tracks, etc.

Unless you specifically need to capture the output from an effect, it is therefore recommended that you record the original video instead of using Rendered Capture. See CL2 Recording for more information.

Stop-Motion Capture will capture single frames from a video stream. This is useful for creating stop-motion animation or timelapse videos.

This node widget can be programmed to take pictures at a regular interval, for example every 5 seconds. The stills are saved in a new folder under the project's current capture session (see CL2 Recording).

To ensure the best image quality, the still pictures will be saved in a format that most closely matches the video source. Often this results in DPX images being saved. You can use Conduit Live to convert the recorded DPX image sequences to another format like QuickTime.

Output

Secondary Display can be used to display an extra image in addition to the one shown in the Viewer. The image can be placed anywhere on the screen, or it can be set to fill another screen.

When combined with Matrox GXM multihead units, this node widget allows you to output on up to 9 screens from a single Mac.

On a computer with multiple PCI Express video cards installed, this node widget can be used to render onto a secondary video card. For best results, you should install the most powerful video card as the primary one, and then use the Secondary Display node widget to render images onto the other video card(s).

Other node widgets

  • Animation Curves: outputs values determined by keyframe animation curves. See CL2 Animation
  • Color Pickers: outputs color picker values as set in the Sliders and Color Pickers window.
  • Convert Value to Video: see explanation above.
  • On-Screen Points: outputs four point values. These points can be set visually in the Viewer window.
  • Slider Bank: outputs slider values as set in the Sliders and Color Pickers window.
  • Switch Values: use this to change the order of a list of values (for example, to make "Slider 4" be the first value in the list).
  • Value Printer: displays the incoming input value. This can be helpful in figuring out what's happening within the project. (The value is displayed in the JavaScript Object Notation (JSON) format, so the printed values can be copied directly into a JavaScript program.)
  • Web Data Source: loads the contents of a web page. This can be used to load text, images or any other kind of content from a web source. The output is a ByteBuffer object. You can use a Script Widget node to convert the object into another type (for example String or Image).


Stage Tools, a special add-on to Conduit Live, contains a number of additional node widgets for hardware input, perspective correction, triggering clips and events, and creating subtitles. For more information, see Stage Tools Overview.


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