The short answer is no. Compression algorithms like winzip, gzip, bzip, etc. are all "lossless" compression - they compress the data by finding a smaller way to represent it without actually changing it. For example, if your file had "AAAAA" you could represent that as "Ax5" and save yourself some space without loosing any information. (The algorithms are actually more complex than that - just trying to give you the idea). But, you're probably not going to get much compression using winrar, winzip, gzip, or anything else. Jpegs are already compressed, so other generic compression programs aren't going to be able to squeeze much more out of them.
You could go through and re-compress them as smaller jpegs using a smaller quality setting, but then you would degrade your images. Jpeg (and MP3, among others) are what's called "lossy" compression. They make files smaller by removing information that isn't critical to how it will be percieved (as well as compressing it in general). So, re-jpeg-ing a picture over and over will cause the quality to deteriorate because you are removing information each time (as opposed to just re-representing it in a smaller way).
Just as a general note, a compression algorithm that will reduce the size of any arbitrary file is the perpetual motion machine of computer science. There is no such thing, although every once in a while someone claims to have done it. Think about it, if you had an algorithm that could compress *any* file, you could just keep going over and over again and again on the same file until it got down to just one bit. With most popular compression algorithms (and bear in mind that jpeg, MP3, etc. are compression algorithms), once you've compressed it that's it. You may be able to squeeze a few more percent out by trying to recompress with another algorithm (i.e. trying to gzip your jpeg collection) but don't count on getting substantial results from doing this. |
