user: Give a detailed overview of Header: syntax, arguments, return values, common patterns.

assistant: [image reference removed]

The Movie Clip Editor header in Mask mode.

### Mode

[Tracking](../../movie_clip/tracking/index.html)
:   For placing markers in a video and tracking their movement.

[Mask](../../movie_clip/masking/index.html)
:   For creating and animating masks.

### View Type

[Clip](../../movie_clip/tracking/clip/index.html)
:   The default view, for placing and tracking markers.

[Graph](../../movie_clip/tracking/graph.html)
:   Plots the movement speed of the markers on a graph.

[Dope Sheet](../../movie_clip/tracking/dope_sheet.html)
:   Shows an overview of marker keyframes on a timeline.

### View Menu

Toolbar `T`
:   Show or hide the tab panel on the left for creating and manipulating markers and masks.

Sidebar `N`
:   Show or hide the [Sidebar](../../interface/window_system/regions.html#ui-region-sidebar).

[Adjust Last Operation](../../interface/undo_redo.html#bpy-ops-screen-redo-last)
:   Display a pop-up panel to alter the properties of the last
    completed operation.

---

Show Metadata
:   Displays metadata encoded in the video, if available.

---

Frame All `Home`
:   Zooms and pans the view so that the whole video is visible.

Frame Selected `NumpadPeriod`
:   Zooms and pans the view to focus on the selected items.

Center View to Cursor Mask Mode
:   Pans the view so that the [2D Cursor](sidebar.html#editors-clip-2d-cursor) is in the center.

Zoom
:   Menu with convenient zoom levels and operations.
    The zoom levels are calculated based on the images resolution compared to the screen resolution.

    - 12.5% (1:8) `Numpad8` zoom out to a factor of 12.5%.
    - 25% (1:4) `Numpad4` zoom out to a factor of 25%.
    - 50% (1:2) `Numpad2` zoom out to a factor of 50%.
    - 100% (1:1) `Numpad1` resets the zoom to 100%.
    - 200% (2:1) `Ctrl`-`Numpad2` zoom in to a factor of 200%.
    - 400% (4:1) `Ctrl`-`Numpad4` zoom in to a factor of 400%.
    - 800% (8:1) `Ctrl`-`Numpad8` zoom in to a factor of 800%.

    Zoom In/Out `Wheel`
    :   Zooms the view in or out.

    Zoom to Fit `F`
    :   Like *Frame All*, but uses as much space in the editor as possible.

---

Area
:   Area controls. See the [user interface](../../interface/window_system/areas.html)
    documentation for more information.

### Select Menu

Menu for selecting [markers](../../movie_clip/tracking/clip/selecting.html)
and [masks](../../movie_clip/masking/selecting.html).

### Clip Menu

Menu for [loading movie clips and creating proxies](../../movie_clip/tracking/clip/editing/clip.html).

### Track Menu

Menu for performing [tracking](../../movie_clip/tracking/clip/editing/track.html) operations.

### Reconstruction Menu

Menu for setting up the [reconstruction](../../movie_clip/tracking/clip/editing/reconstruction.html)
of 3D information from the tracked points in the 2D video.

### Add Menu

Use to add primitive mask shapes.

Circle
:   Adds a circle-shaped mask.

Square
:   Adds a square-shaped mask.

### Mask Menu

Menu for operators used to [Edit](../../movie_clip/masking/editing.html) masks.

### Other

Clip
:   A [data-block menu](../../interface/controls/templates/data_block.html#ui-data-block) used for loading and selecting movies.
    Both video files and image sequences can be used.
    When a movie clip is loaded into the Clip editor, extra panels are displayed in the interface.

Pivot Point
:   See [Pivot Points](../3dview/controls/pivot_point/index.html).

Proportional Editing Mask Mode
:   See [Proportional Editing](../3dview/controls/proportional_editing.html).

Mask Mask Mode
:   A [data-block menu](../../interface/controls/templates/data_block.html#ui-data-block) for creating and selecting masks.

Mask Display Mask Mode
:   See [Mask Display](display/mask_display.html).

Toggle Lock Selection `L`
:   Automatically pans the view to follow the selected markers,
    so that they remain in the same location on screen during tracking and playback.

    This option “locks the view onto the selection” and is not to be confused with the
    [Lock](../../movie_clip/tracking/clip/sidebar/track/track.html#bpy-types-movietrackingtrack-lock) option in the Sidebar,
    which instead prevents you from changing the active marker.

Clip Display
:   See [Clip Display](display/clip_display.html).

Gizmos
:   See [Viewport Gizmos](display/gizmo.html).