15 Best Free Image Optimization Tools for Image Compression
PNGGauntlet allows you to optimize your PNG photos. It is downloadable and combines with multiple compressors like PNGOUT, OptiPNG and DeflOpt to compress your images without effecting the image quality. It will also work convert and compress JPG, GIF, TIFF, and BMP to PNG files. On the downside it does take a little longer then the other options.