mp3s use complex compression algorithms to reduce file sizes, so an on-calc player for them isn't feasible, let alone one that reads usb and playss at the same time. you could write an application to read and play simpler files, maybe something that reuses code directly from usb8x when it's on the calculator, but it would be difficult, time consuming, and, with the proclivity of smaller, cheaper devices with larger internal storage space and the ability to decode better compression formats, ultimately pointless.
it would be cool, though

It would be pretty cool if that would be possible. Maybe the song could be loaded into a different format before the calc starts reading&playing it?

damn it. I swore there was a video of it. I just assumed the first links i got were the right ones without looking into it much.

We can already play MP3's as shown here: http://www.ticalc.org/archives/files/fileinfo/354/35424.html
And we can already download from flash drives as shown here: http://www.ticalc.org/archives/news/articles/13/139/139572.html

So why not combine the 2? You would have a program that downloads "chunks" of data from the drive, plays them, and then deletes them. This would obviously have problems, the first coming to mind is speed, but does this seem like a possiblity?

Well, first of all, I'd like to point out that the "MP3's" you are talking about are similar to MIDI files. (Old cell phone ringtones).


The 84+ has been able to play music for quite some time now. It started real Real Sound (the video is gone) which could only work on the calculators with the extra ram. Then I made TruSound (youtube) which allowed the newer calculators to play sounds as well.

Now, both of these programs played .WAV files. If you know much about song formats, you know that .WAV files can be around 5x as big as MP3 files. The reason for this is that MP3 files are compressed to a smaller size. Like shmibs said, this compression algorithm is very complex and some computers running windows 2000 cannot even play them properly without skipping. What makes .WAV files convenient is that they are already in the format that is required to play sound while MP3 is not.

The obvious solution to the MP3 problem would be to decode the files ahead of time, but the 84+ only has 48KB or 128KB of ram (HW differences) and at 128Kbps, that means you'll get either 3 seconds or 8 seconds of song before the program would have to decode the next section which could take another 3 to 8 seconds. (TruSound uses a little compression, but it only cuts off around 20% of the file size)


Anyways, that's why MP3 doesn't work. As far as the USB half of it, I didn't think it was possible, but SirCmpwn proved us wrong. The trouble with sound over USB is that you have to try to get the USB port to cooperate with you fast enough to keep up with the song. Not only that, but you have to manage your cpu time because playing sound requires around 60% of the processor time when optimally configured and USB is a finicky thing that doesn't like to be interrupted.

Now, I say SirCmpwn proved us wrong, but like everyone has said, he never actually released his program. So while his youtube video made the music sound nice, I would honestly bet that it was a little scratchy. But, to be fair, he did manage to play recognizable music from a flash drive.


Finally, since you seem to be excited about playing songs on your calculator, I'll have to point you to another one of my projects, TruVid. (youtube)

Is it very hard to just constantly download data from a USB to the calculator ARC or RAM and delete every byte when it has been played and could the same ever be possible for video? Because that would mean that the amount of data you can use becomes unlimited