If you have a large music collection, and have to cull it to squeeze as much as possible on your iPhone or iPod, you may want to look at another way to save space. If you have album artwork for all your tracks, you may want to consider checking how much space it takes up.
When you add album art to an album, it gets copied to every track. So, if an album has ten tracks, and you add album art that takes up 200 K, you’ve added about 2 MB to the size of your music. If your album art for that album is 1 MB, then that’s 10 MB. And so on.
If you manually add album art to songs, you have many choices. You can search Google for the artist and album, and, in most cases, find a number of appropriate images. They come in varying sizes, and a couple of different formats.
The first way to save space is to choose smaller images. I went looking for album art for the Grateful Dead’s Live/Dead album, and found lots of choices.
The one above is 600 x 606 pixels; I find that to be an appropriate size. It displays well on my iPhone, and on my Apple TV. (Apple provides 600-pixel artwork with music it sells.) But if you only look at your album art on a portable device, you may find that 300 x 300 pixels is sufficient; for an equivalent image, this takes up 1/4 the space.
There is also the question of format. The above image is a JPEG, and it takes up a mere 74 K; that’s pretty small. Apple’s equivalent image is about 200 K, but it does have more detail, and it’s a PNG. JPEGs are generally smaller, but, depending on the level of compression used, they may not look as good.
At the other end of the spectrum, I found a 1423 x 1423 PNG which looks very nice, but it takes up 4.7 MB. That’s about as much space as a three-minute song at 256 kbps. If all your artwork is that size, you’ll be using about half the space on your iPod or iPhone for artwork.
So think carefully before you add huge album art to your music. It will take up a lot of space in your iTunes library, and on your portable device.