How to change gradient photo to white in one-inch portrait

Quick answer：

To change a gradient photo to white in a one-inch portrait, you can use photo editing software such as Adobe Photoshop or GIMP. Open the photo, adjust the levels or curves to lighten the colors and make them white. Alternatively, you can use the 'Hue/Saturation' adjustment to desaturate the colors and then use the 'Brightness/Contrast' to lighten the image until it turns white.