httpZip now compresses Bitmap and PNG files by default. What about other images like GIFs and JPEGs?
httpZip will compress any type of file that you like — it is the most configurable of HTTP compression tools for IIS — but we have very safe settings for image compression to avoid known browser decompression issues. You will notice in the main Compression tab that we do compress two image file types: BMP and PNG (in the case of Internet Explorer 7). These files are not usually compressed when created, and so they benefit from compression. Port80 did not add GIF and JPEG files to default compression in httpZip for a good reason — these files are already compressed with lossless compression when they are created in an image editor (like Photoshop or Acrobat). You can compress JPEG files by adding the MIME sub-type “jpeg” under the top-level MIME type “image” under the Mime Types window on the Compression tab of the Settings Manager (and similarly add GIF files for compression in httpZip), but the files may actually increase in size or the images may be distorted from duplicative comp
