Node.js GM quality() Function

Last Updated : 30 Mar, 2023

The quality() function is an inbuilt function in the GraphicsMagick library which is used for JPEG/MIFF/PNG/TIFF compression levels. If the filter type is 4 or less, the specified filter type is used for all scanlines:0: none, 1: sub, 2: up, 3: average, 4: Path. The function returns the true value on success.

Syntax:

quality( level )

Parameters: This function accepts a single parameter which is mentioned above and defined below:

level: This parameter is used to specify the level of the quality.

Return Value: This function returns the GraphicsMagick object.

Example 1:

javascript

// Include gm library
const gm = require('gm');
 
// Import the image
gm('1.png')
 
// Invoke quality function with
// average parameter
.quality(3)
 
// Process and Write the image
.write("quality1.png", function (err) {
      if (!err) console.log('done');
});

Output:

Example 2:

javascript

// Include gm library
const gm = require('gm');
 
//Import the image
gm(600, 300, 'white')
 
// Set the color for the stroke
.stroke("green", 3)
 
// Set the font 
.font("Helvetica.ttf", 60)
 
//Call to drawText Function
.drawText(100, 280, "GeeksforGeeks!")
 
// Invoke quality function with
// sub-option via 1 
    //  0: none
    //  1: sub
    //  2: up
    //  3: average
    //  4: Paeth
.quality(1)
 
// Process and write the image 
.write("quality2.png", function (err) {
      if (!err) console.log('done');
});