In fact all the rating information in the sansa clip can somehow be retrieved, which means from 0 star to 5 stars. It depends on which side the tracks are. If the tracks are on the MTP side the rating can be read by any program aware of MTP protocol. There would be a “User rating” tag for the tracks with none-zero rating, the value ranges from 0 to 100. One can scale this value to any rating system, in principle.
If the tracks are on the MSC side, the story is a bit tricky. All the information is stored in the MTABLE.SYS file under the root directory in MSC mode. The file is some kind of database for all the tracks and rating. The rating information starts from address somewhere aound #A41300, each rating occupies 4 byte, first one is always #80, the next one is the rating #00 to #05, followed by two byte #0000. To find out which track this rating corresponds to one has to look into the starting of this file, where the corresponding track information is listed in the same order. The information is stored in the following format:
‘path’ #0000 ‘filename’ #000000 “track name” #0000 “artist” #0000 “album” #0000FFFF0000 “genre” #0000 ‘track/total(8 wordslong)’
Word in ‘’ means the encoding is in ASCII or other extensions compatible to vfat.
Word in “” is in UTF-16.
The path is expressed as, for example ‘mmc:0:\MUSIC\NAME’
the example for ‘track/total’ is ‘00000410’, means the track is 4/10
Another tricky parts is, it seems that there are some wav files registered in the database. But there is no rating for them in the database. They are skipped somehow in the rating file sequence.
As a summary, yes, it is possible to get the rating, but it is highly non-trivial, especially in MSC mode.