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' );
}); |
Output:
Reference: