When I take pictures with my camera the file sizes seem exceedingly large. In this example the original is 5186kb. I wrote a java program to just read the image and then write it again, removing any information except the pixel values.
The first time it is rewritten, the file size goes down to 1005kb, over a 500% reduction! To make sure I wasn't losing data to compression I iterated the program 100 times on the resulting images and the file size stayed at exactly 1005kb with no loss in image quality.
My question is, what is the camera storing in the other 4181kb? Some sort of metadata I know, but it seems like a lot. I would like to know what I am losing by resizing my images like this.
Assuming the file format you are using is
.jpg, the original file was saved in a higher value of jpg compression say 95%, while when you resave the file, you probably were using say 85% jpg compression value.The size doesn't change in consequent saves as the compression value stays the same