Letterbox

Fills the top and bottom rows of each frame, and optionally the left and right columns, with black or color. This has several common uses:

  • Black out video noise from the existing black bands in an image that's already letterboxed.

  • Black out the video noise at the bottom of the frame in VHS tape sources.

  • Black out overscan areas in VCD or SVCD sources.

  • Create a quick rectangular mask for other filters – a so-called "garbage matte".

See also: AddBorders, which increases frame size. Letterbox does not change frame size.

The functionality of Letterbox can be duplicated with a combination of Crop and AddBorders, but Letterbox is faster and easier.

Generally, it's better to Crop video noise off than to black it out; many older lossy compression algorithms don't deal well with solid-color borders, unless the border happens to fall on a macroblock boundary (16 pixels for MPEG). However, in some cases, particularly for certain hardware players, it's better to use Letterbox because it lets you keep a standard frame size.

Syntax and Parameters

Letterbox (clip, int top, int bottom, int "x1", int "x2", int "color", int "color_yuv")
clip

Source clip; all color formats supported.

top, bottom

Number of top and bottom rows to blank out.

  • For YUV420 sources, top and bottom must be mod2 (divisible by 2).

x1, x2

Number of left (x1) and right (x2) columns to blank out.

  • For YUV422 and YUV420 sources, left and right must be mod2 (divisible by 2).

  • For YUV411 sources, left and right must be mod4 (divisible by 4).

Default: 0, 0

color
Fill color specified as an RGB value in either hexadecimal or decimal notation.
Hex numbers must be preceded with a $. See the colors page for more information on specifying colors.

  • For YUV clips, colors are converted from full range (0–255) to limited range (16–235) Rec.601.

  • Use color_yuv to specify full range YUV values or a color with a different matrix.

Default: $000000

color_yuv
Specifies the fill color using YUV values. Input clip must be YUV.
See the YUV colors section for more information.

Changelog

Version

Changes

AviSynth+ 3.4.1

Added color_yuv option.

AviSynth+ r2487

Added support for RGB48/64 and all Planar RGB(A)/YUV(A) color formats.

AviSynth 2.0.7

Added color option.

AviSynth 2.0.6

Added optional left and right parameters (x1 and x2).

$Date: 2022/02/08 11:37:04 $