Evil Dr Ganymede wrote:You'd think... But they use their own proprietary formats and compression schemes, which are hideously clunky but do the job they want them to do. I think it might be so that they can put their own image headers and labels on the top of the files, which you can't do with PNGs or GIFs.
The astronomy and space research communities have some 40 years of experience capturing images and other data in space for transmission to Earth. When the Voyager images from Saturn were sent around 1980, state of the art graphics for off-the-shelf personal computers provided, say, eight colours and pretty low resolution (and many users were satisfied with b/w). The science community required a lot better, and thus had to develop their own formats and software. GIF came in the 1980's, but was hardly sufficient for science imaging. Maybe PNG would do well today, but I don't see much benefit in a general switch, scrapping years of software development for them.
I remember reading that the Voyager spacecrafts received new data compression software over the radio long after launch, to overcome some of the physical limitations incurred by broken transmitters, stuck antennas or whatever damages they had appearantly suffered in the asteroid belt. For 1970's technology, I consider that pretty amazing.
Evil Dr Ganymede wrote:I don't know too much about the format that the cameras actually save the images as, I deal more with turning those into processed images.
Browsing the Cassini raw (?) image archive, I can hardly find any images with similar compression artefacts as those from Huygens. Maybe Cassini can afford to do less compression, thanks to higher bandwidth in the Earth communication link?