Originally Posted by pruss
You could also reduce the compression accuracy of the jpeg files. I've just posted a new version of explode with a --jpeg-quality=xxx switch (untested). I noticed that the previous version always set the quality to 100 (!). If you set it to 85 or so, you might find a nice improvement, unless of course your further conversion tools themselves reduce the jpeg quality.
Actually, I was thinking of using instead (in place) .gif images with 256-colors (yields about 50% filesize savings) and will see if using a 16-color/grayscale .gif will reduce this any further. Worth a shot!
However, I will also try your new --jpeg-quality switch. "Whatever works best" is my motto...