I have defined some ImageDescriptors to get different sizes of the uploaded images depending on where they will be previewed on the website. I have noticed that some of the resized images is a lot larger than the original. I uploaded an image which was 250kb and the resized one (which happend to be resized to the same size as the original) became about 2.7mb large. I have also noticed that the resized image is in .png and not in .jpg as the original, which probably is affecting the size a lot. Is there a way that I can specify the file type of the resized image? Is there anything else I can do about this? The whole purpose of resizing images is to get the file size smaller....
Episerver stores resized images in PNG format by default.
See this post if want to store your resized images in the same mime type:
Storing your thumbnails in the correct mime type
Hope this helps.