How to use the blueimp-load-image.scale function in blueimp-load-image

loadImage(file, canvas => {
        if (canvas.type === 'error') {
          return alert('The image could not be loaded.')
        }

        const scaled = loadImage.scale(canvas, {
          maxWidth: 400,
          maxHeight: 300,
          crop: true,
          downsamplingRatio: 0.5,
        })

        scaled.toBlob(blob => {
          this.setState({
            imageURL: URL.createObjectURL(blob)
          })

          this.props.onSelect(blob)
        }, 'image/jpeg')
      }, {
        // loadImage options

image.addEventListener('load', () => {
      // using components/blueimp-load-image

      // first, make the correct size
      let canvas = loadImage.scale(image, {
        canvas: true,
        cover: true,
        maxWidth: size,
        maxHeight: size,
        minWidth: size,
        minHeight: size,
      });

      // then crop
      canvas = loadImage.scale(canvas, {
        canvas: true,
        crop: true,
        maxWidth: size,
        maxHeight: size,
        minWidth: size,
        minHeight: size,
      });

      const blob = dataURLToBlobSync(canvas.toDataURL(contentType));

      resolve(blob);
    });

this.inputImageShape = [img.height, img.width]
            const outputCanvas = document.getElementById('output-canvas')
            outputCanvas.width = img.width * 2
            outputCanvas.height = img.height * 2
            this.outputImageShape = [img.height * 2, img.width * 2]
            const scaledInputCanvas = document.getElementById('scaled-input-canvas')
            scaledInputCanvas.width = img.width * 2
            scaledInputCanvas.height = img.height * 2

            // load image data onto input canvas
            inputCanvas.getContext('2d').drawImage(img, 0, 0)
            this.imageLoadingError = false
            this.imageLoading = false

            // bilinear scale input image to compare to
            const scaledImg = loadImage.scale(img, { minWidth: img.width * 2, maxWidth: img.width * 2 })
            scaledInputCanvas.getContext('2d').drawImage(scaledImg, 0, 0)

            // run model
            this.modelRunning = true
            this.modelRunningError = false
            this.$nextTick(function() {
              setTimeout(() => {
                this.runModel()
              }, 10)
            })
          }
        },
        { maxWidth: this.srcMaxWidth, canvas: true, crossOrigin: 'Anonymous' }

image.addEventListener('load', () => {
      // using components/blueimp-load-image

      // first, make the correct size
      let canvas = loadImage.scale(image, {
        canvas: true,
        cover: true,
        maxWidth: size,
        maxHeight: size,
        minWidth: size,
        minHeight: size,
      });

      // then crop
      canvas = loadImage.scale(canvas, {
        canvas: true,
        crop: true,
        maxWidth: size,
        maxHeight: size,
        minWidth: size,
        minHeight: size,