GUI previewer

pixelflow-gui opens a desktop preview window for PixelFlow .pf scripts.

Launching

Run without arguments to open a blank window with a centered Open Script button:

pixelflow-gui

Run with a script path to open it immediately:

pixelflow-gui path/to/script.pf

While the startup script is loading, the blank window shows a loading indicator instead of the Open Script button. The GUI accepts only .pf input paths.

Plugin directories

pixelflow-gui scans conventional platform plugin directories by default. Set PF_PLUGIN_DIRS to replace that list entirely. The same directory list is used for compiled plugins and script plugins.

PF_PLUGIN_DIRS uses the operating system path-list rules. In typical shell usage, separate multiple entries with : on Unix and macOS or ; on Windows. Empty path-list entries are ignored. Set PF_PLUGIN_DIRS to an empty value to disable plugin directory scanning.

Preview workflow

When a script opens successfully, the previewer evaluates the script, indexes reachable FFMS2 sources, validates the final graph, prepares built-in executors, and renders frame 0 by default.

Use any of the navigation controls below the preview image to inspect the clip:

• frame number input,
• zoom dropdown, and
• position bar.

Entering an empty frame number seeks to frame 0. Entering a frame number greater than the final frame seeks to the final frame instead.

Side panel

The side panel has two tabs:

• Props lists metadata props for the current rendered frame.
• Histogram shows one level histogram per plane for the current rendered frame.

Histogram graphs use the pixel value on the X axis and the number of pixels in each bucket on the Y axis. Integer formats use the logical pixel-value range from 0 to the maximum value supported by the format bit depth. Float formats use 0.0 to 1.0. Higher bit depths and float formats are bucketed to fit the side panel.

The histogram tints the left and right edges of each graph to show values outside the limited legal range for that plane.

Keyboard shortcuts

When the preview window has keyboard focus, use these shortcuts:

When the frame number input has keyboard focus, plain Left and Right edit the text cursor instead of navigating frames. The Ctrl/Cmd shortcuts still act on the preview.

Zoom and scrolling

The zoom dropdown offers these fixed percentages:

• 25%
• 50%
• 75%
• 100%
• 200%
• 400%
• 800%
• 1600%

Hold Ctrl and scroll the mouse wheel while the pointer is over the preview panel to zoom one step at a time. Plain mouse-wheel scrolling pans the zoomed preview when scrollbars are available. You can also pan by dragging the preview with the primary mouse button or by dragging the scrollbars.

Status bar

When a script is open, the status bar shows:

• format,
• resolution,
• frame count,
• FPS, and
• duration.

While a frame render is pending, the status bar appends a small text spinner and Loading frame. While the current script is reloading, it appends the same spinner and Reloading script.