image-output

Output image data to a destination: file, canvas, console, stdout, ImageData etc.

Usage

var output = require('image-output')

// create chess pattern png from raw pixels data
output({
	data: [0,0,0,1, 1,1,1,1, 1,1,1,1, 0,0,0,1],
	width: 2,
	height: 2
}, 'chess.png')

API

output(source, destination?, shape|options?)

Output pixel data source to a destination based on options. Undefined destination displays image to console/stdout. The operation is done in sync fashion. destination and options may come in the opposite order for conveniency.

output([0,1,1,0], [2,2,1], 'a.png')

source

Shoud be an actual image data container, one of:

• Canvas, Context2D, WebGLContext
• ImageData or Object {data: Uint8Array, width, height}
• DataURL or base64 string
• Image, Video, ImageBitmap with resolved data
• Array, Array of Arrays, Uint8Array, FloatArray with raw pixels
• ArrayBuffer, Buffer
• Ndarray

Handy for that purpose is image-pixels:

var pixels = require('image-pixels')
output(await pixels('image.png'), 'image-copy.png')

destination

Can be any image output destination:

Type | Meaning ---|--- String | File to create or path, in node. If includes extension, mimeType is detected from it. Canvas2D, Context2D | Render pixel data into a canvas. Canvas is resized to fit the image data. To avoid resizing, use options.clip property. document, Element | Create a canvas with diff data in document or element. console | Display image to console in browser or to terminal in node. Array / FloatArray | Write pixel data normalized to [0..1] range to a float-enabled array. UintArray | Put pixel data to any unsigned int array. Buffer / ArrayBuffer | Put pixel data into a buffer, possibly encoded into target format by options.type. Ndarray | Write pixel data into an ndarray. ImageData | Put data into ImageData instance, browser only. Object | Create data, width and height properties on an object. Function | Call a function with ImageData as argument. Stream | Send data to stream, eg. process.stdout. WebStream | TODO. Send data to stream, eg. process.stdout.

options

Property | Meaning ---|--- type / mime | Encode into target type, by default detected from file extension. By default image/png. quality | Defines encoding quality, 0..1, optional. By default 1. ...rest | Rest of options is passed to encoder.

Customize color palette in terminal

You can choose color palette with flags or environment variable FORCE_COLOR=0123

node ./script.js --no-color
node ./script.js --color
node ./script.js --color=256
node ./script.js --color=16m

Related

• image-equal − compare if two images are equal.
• image-pixels − load image data from any source.
• image-encode − encode image data into one of the target formats.

Similar

• save-pixels − output ndarray with image pixels to a file.
• terminal-image − print image to a terminal.

License

© 2018 Dmitry Yv. MIT License.