AT3 files... what are they what have you tried?

[Cirbirus]

[quote name="Pulp_Fiction"]
Since flat out replacing one file with a MP3 or other file affects the next or previous (damn, I can't remember which put I posted it somewhere) song then there may be something to the previous affecting the preceding thing you said.[/quote]

Yeah I remember reading that post. And it scares me. Oddly the second track01 file you replaced, the one from a different album, shouldn't have worked. But it might be really good news, the header info might not matter, which I can't believe, but I still have to figure out the database structure so I can write something that will convert and add our MP3's to the Z1's hard drive automagically.

Can you send me a Dir of the entire drive, for each partition. I didn't realize that each album had some kind of directory structure. In fact I don't know the first thing about the dir structure so that would be a huge help. Man I can't wait to get my unit....

Oh, does anyone know where I can get my hands on the ATRAC SDK? I know Sony has released it in a limited maner but it doesn't seem to be easily found. It would be really helpful if I knew more about ATRAC and the SDK would allow me to write the conversion ability directly into my transfer application.

[Pulp_Fiction]

[quote name="Cirbirus"] [quote name="Pulp_Fiction"]
Since flat out replacing one file with a MP3 or other file affects the next or previous (damn, I can't remember which put I posted it somewhere) song then there may be something to the previous affecting the preceding thing you said.[/quote]

Yeah I remember reading that post. And it scares me. Oddly the second track01 file you replaced, the one from a different album, shouldn't have worked. But it might be really good news, the header info might not matter, which I can't believe, but I still have to figure out the database structure so I can write something that will convert and add our MP3's to the Z1's hard drive automagically.

Can you send me a Dir of the entire drive, for each partition. I didn't realize that each album had some kind of directory structure. In fact I don't know the first thing about the dir structure so that would be a huge help. Man I can't wait to get my unit....

Oh, does anyone know where I can get my hands on the ATRAC SDK? I know Sony has released it in a limited maner but it doesn't seem to be easily found. It would be really helpful if I knew more about ATRAC and the SDK would allow me to write the conversion ability directly into my transfer application.[/quote]

I posted the full file list earlier here: [url]http://avic411.com/forum/download.php?id=194[/url]
Each file name in the zip is a partition.

[Cirbirus]

When you said the file played even when you replaced a much larger file with my file it got me thinking. The codec seems to be a packet based protocol so it might be able to work without knowing what is next (wav files can work this way so it makes sense).

So, I need you to try this file. It is a file that has the Z1 header and only data generated from the PC. It should be the first track from that Offspring album when played on the Z1. If it works this is fantastic news since I can't find what looks like header information in any of the files from the Z1.

You'll notice the file is smaller than the original Z1 file, that's because of the extra 4 seconds of silence in the Z1.

Interesting note. Silence to the Z1 looks slightly dirty, like it's got some noise in the circuit or something. That doesn't make a whole lot of sense in a digital signal but I'm just guessing at this point.



Oh, I remember reading something in the Z1's user docs about the 2-second delay when recording, can you turn that off? That way the files will be the same size in the future when you rip a file on the Z1.

[Pulp_Fiction]

I'm going to try your latest file shortly (next trip to the car) but in the meantime here is something for you to look at.
The attached file is a wave of 1 min. of complete silence created by goldwave and the resulting AT3 of the same file after being burned to a CDR and ripped by the Z1.
Perhaps knowing it is silence you will have better luck pulling off the headers????

Don't know about the 2 second thing. I'll look in the menus when it's back together.

[Pulp_Fiction]

[quote name="Cirbirus"]When you said the file played even when you replaced a much larger file with my file it got me thinking. The codec seems to be a packet based protocol so it might be able to work without knowing what is next (wav files can work this way so it makes sense).

So, I need you to try this file. It is a file that has the Z1 header and only data generated from the PC. It should be the first track from that Offspring album when played on the Z1. If it works this is fantastic news since I can't find what looks like header information in any of the files from the Z1.

You'll notice the file is smaller than the original Z1 file, that's because of the extra 4 seconds of silence in the Z1.

Interesting note. Silence to the Z1 looks slightly dirty, like it's got some noise in the circuit or something. That doesn't make a whole lot of sense in a digital signal but I'm just guessing at this point.



Oh, I remember reading something in the Z1's user docs about the 2-second delay when recording, can you turn that off? That way the files will be the same size in the future when you rip a file on the Z1.[/quote]


Same result as before. File plays but sounds like it is a data CD.

[Cirbirus]

Excellent info!

The silence from the GoldWave app is true silence and what I found most interesting is that there are no A2h markers every C0h bytes. The A2h byte value repeating every C0h bytes is what made me think that the ATRAC codec was a packet based system. It still may be but this means it doesn't have a header byte. Since it doesn't have an end marker or any kind of checksum data and every block of data is the exact same size (192 bytes) it makes sense that you don't need a header marker.

The info in the header of the standard AT3 file must tell the consumer app what the bit-depth and sample rate are (plus the length of the data segment) but the Z1 always uses the same settings so maybe that info isn't needed so the header isn't needed and it knows when the file ends because, well, the file has ended.



Damn, I didn't see your post about the latest file still sounding like garbage. Double damn.

Oh, are you using a drive that doesn't support locking or did you set the the drive to unlockable?

[Pulp_Fiction]

[quote name="Cirbirus"]Excellent info!

The silence from the GoldWave app is true silence and what I found most interesting is that there are no A2h markers every C0h bytes. The A2h byte value repeating every C0h bytes is what made me think that the ATRAC codec was a packet based system. It still may be but this means it doesn't have a header byte. Since it doesn't have an end marker or any kind of checksum data and every block of data is the exact same size (192 bytes) it makes sense that you don't need a header marker.

The info in the header of the standard AT3 file must tell the consumer app what the bit-depth and sample rate are (plus the length of the data segment) but the Z1 always uses the same settings so maybe that info isn't needed so the header isn't needed and it knows when the file ends because, well, the file has ended.[/quote]

Cool, silence is golden when used correctly!

Sounds like Pioneer created the music interface from scratch (thus less header info) and just used the AT3 codec. WHY AT3??? Sony must have been the lowest bidder on the block that day.

[miraculousboy]

[quote name='Pulp_Fiction' timestamp='1149875916' post='3550']
Are you able to play them in anything? I'm concerned they are encrypted in some way.
[/quote]
yes you can download sonicstage and play them, but i need to figure out how to conver mp3/wma to at3 so i can copy my library over.