gulp-resize-img.js

var responsive = require('gulp-responsive');
var load = require('gulp-load-plugins')();

gulp.task('resize-img', function () {
  return gulp.src('img/*.{jpg,png}')
    .pipe(load.responsive({
      '*.jpg': [{
        width: 100,
        rename: {
          suffix: '-thumb',
        }
      }, {
        width: 300,
        rename: {
          suffix: '-medium',
          // extname: '.jpg',
        },
      }, {
        width: 900,
        rename: {
          suffix: '-big',
        },
        // Do not enlarge the output image if the input image are already less than the required dimensions.
        withoutEnlargement: true,
      }],

      '*.png': [{
        width: 100,
        rename: {
          suffix: '-thumb',
        }
      }, {
        width: 300,
        rename: {
          suffix: '-medium',
          // extname: '.jpg',
        },
      }, {
        width: 900,
        rename: {
          suffix: '-big',
        },
        // Do not enlarge the output image if the input image are already less than the required dimensions.
        withoutEnlargement: true,
      }]

    }, {
      // Global configuration for all images
      // The output quality for JPEG, WebP and TIFF output formats
      quality: 70,
      // Use progressive (interlace) scan for JPEG and PNG output
      progressive: true,
      // Strip all metadata
      withMetadata: false,
      // Do not emit the error when image is enlarged.
      errorOnEnlargement: false,
    }))
    .pipe(gulp.dest('img/dist'));
});