Code Samples

For code samples of LUT-based image manipulation, please check out our lut-examples repository.

Lookup Table

Usage

Lookup Table - CLI Example

metrical shape lut [OPTIONS] --camera <CAMERA> <INPUT_PLEX> <ARTIFACT>

Lookup Table - Manifest Example

command = "shape-lut"
input-plex = "{{calibrate-stage.results}}"
format = "json|msgpack"
camera = "camera_to_generate_lut_for"
artifact = "{{auto}}"

Purpose

It's not always easy to adopt a new camera model. Sometimes, you just want to apply a correction and not have to worry about getting all of the math right. The LUT subcommand gives you a shortcut: it describes the locations of the mapped pixel values required to apply a calibration to an entire image.

Note that a lookup table only describes the correction for an image of the same dimensions as the calibrated image. If you're trying to downsample or upsample an image, you'll need to derive a new lookup table for that image dimension.

These lookup tables can be used as-is using OpenCV's lookup table routines; see this open-source repo on applying lookup tables in OpenCV for an example.

Examples

Create a correction lookup table for camera ir_one

metrical shape lut --camera ir_one <INPUT_PLEX> <ARTIFACT>

Arguments

[INPUT_PLEX]

The path to the input plex. This can be a MetriCal Results MCAP or a plex JSON.

[ARTIFACT]

The artifacts output location.

Options

Global Arguments

As with every command, all global arguments are supported (though not all may be used).

-a, --camera [CAMERA]

The camera to generate a LUT for. Must be a camera component reference such as a UUID or component name.

-f, --format [FORMAT]

Default: json

What serializer to use to format the output. Possible values:

• json: Output the shape data as JSON
• msgpack: Output the shape data as MsgPack