Rockbox Technical Forums
Support and General Use => Audio Playback, Database and Playlists => Topic started by: drayon on August 08, 2007, 08:01:54 AM
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Hi, i have the iPod Mini G2. I have some Toast CD-DA disc images mounted an i copied the files to the iPod with rockbox. However the aiff's will not play. I read a AIFF thread concerning the limitations. I've got no i dea exactly what they are talking about eg
"Currently the data chunks must be in order, this means the format info chunk 'COMM' has to come before the audio data 'SSND' chunk"
What on earth is that supposed to mean? I've dealt with audio on a pro level for many years an have never heard terminology reference to data chunks before. I've created millions of Aif's over the years an never had an issue with anything playing them except this rockbox OS. Data chunks, could they actually be talking about Little & Big Endian byte order or FourCC ?? Anywayz iam still using PowerPC hardware so all my audio files are big-endian, id imagine Apple are now using little-endian the new intel based Mac's.
Maybe little-endian AIFF works on the rock box an not big-endian??
Anyone know? thanks
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http://preserve.harvard.edu/standards/audioiffspecification1-3.pdf
http://en.wikipedia.org/wiki/AIFF
As you can see, "Chunks" are an integral part of describing the workings of AIFF. As well, standard AIFF is defined to be big endian. Are you sure your files are standard and not compressed?
I assume that by "on a pro level" you mean you've used software designed to create AIFF files, rather than created software to use AIFF files. This information isn't really of a concern if your software handles it for you, but it is fundamental to the format.
Of course, if you don't tell us what error message or problem you're getting with your AIFFs, whether you've tried other formats, and what method you used to create the AIFF files, there's very little advice anyone can give you.
As a note, "anywayz" is not a word, please attempt to use proper English words and spellings as per the forum guidelines.
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Some time ago I also experienced that the AIFFs created by some applications worked while others not.
I never took the time to experiment all the way with this though...
The usual stuff:
How old is your RB build?
Can you upload some files that are not working?
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Hi Llorean,
My AIFF's are not compressed, I never compress any audio. Your assumption is correct, I mean't of course recording audio on the Mac at a pro level, not software development.
The error message I see is simply "no file" & a '?' where the bit rate should be. The AIFF's in question are sourced from CD-DA disc images extracted with Roxio's Toast. I simply mount the disc images in the Finder on the Mac and then copy the mounted image to the iPod. This sequence creates a directory on the iPod using the name of the mounted disc image will all the files with track names as is in the image. None of these play. I even tried Max to convert the files using Core Audio AIFF big-endian no dice. Finally i managed to convert them using 'libsndfile' AIFF (Apple/SGI) Signed 16bit PCM in Max which then played in the iPod RockBox. But thats a heck of a lot of messing about, considering everything else just plays the AIFF's straight off the disc image or from a copied image into a directory.
RockBox version is r14115-070801
I notice either Rockbox is very unstable or my iPod mini's hardware is defective because I have allot of crashing, FLAC audio files dropping out for a few ms during playback, extremely slow file x-fer rates and general slowness. (Disc data rates are attributed to the FS FAT32. even with Apple's OS i noticed significant slow down of disc data rates/access times when it is FAT32 formatted compared to HFS+). Along with charge/power issues, I have this iPod connected to mains power all night, take it off power, fire it up an battery charge is reported as only 70% which rapidly evaporates after 30mins then shuts down. Often it shows practically no charge at all after being on all night. When i first experienced this was when i was charging over USB which i thought was the problem an thus to be re-calibrated correctly i needed to buy a AC mains power adapter to charge it. Well there is no change, it has lousy batter life and crashed all the time, this would suggest defective hardware rather than the RockBox OS.
Do you happen to have a preferred or recommended player to run your OS? I have space in my trash can for this iPod Mini :-(
Best
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Depends specifically on what functionality you want out of it. Since you're using an iPod, I'm assuming things like "Recording" and "Radio" aren't high on your list. Though the size is larger, the Gigabeat F is quite a nice player. Honestly, nothing iPod Mini-sized or smaller really works very well right now (they're nearly all portalplayer based and essentially have the same problems as ipods) except for the Ondio models, and those aren't going to play any of the lossless formats you like.
I'm still curious about those AIFFs. Can you provide more information about specifically what they contain, as the creation process doesn't mean anything to someone who doesn't use that software. For example, I'm assuming they should be 44.1khz, 16-bit, since they're a direct rip of a CD. But you could check on the chunks. I'm assuming you there's some sort of utility that can provide information about the files (for example, for repairing a corrupted file if you don't have the original source, etc) out there somewhere.
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Hi again Llorean,
Player functionality- Just playback of AIFF, FLAC, MP3 (cringe). Radio a definite NO, recording not essential. My main interest would be in the actual DA Convertors and IC OP Amps (most accurate/transparent) don't particularly like the sound of the iPod.
AIFF - 16 bit 44k un-altered. Ill probe a little deeper into obtaining lower level info on the files. Im sure there is a terminal command to retrieve the data, just a matter of locating the correct group of ppl who would know, i may investigate in the apple core audio developer mailing lists.
Speak soon man
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You might be interested in the BuyersGuide wiki page at http://www.rockbox.org/wiki/BuyersGuide (and before you dump your mini in the trash can you might consider donating it to some interested developer ;))