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pkfox
2014-10-03, 06:48
Hi all, I have some .aac files which play perfectly well using vlc but wont play on my Transporter ( no error just silence ) is there something I need to do to enable them to be played ?

pippin
2014-10-03, 10:50
Is your server not able to transcode? Transporter doesn't support AAC so it needs to be transcoded

bpa
2014-10-03, 12:16
Since you can now play AAC streams (as detailed in another thread) I'm assuming transcoding is OK so the problem would seem to be the AAC file.

Do these files have any embedded video / images ?

pippin
2014-10-03, 14:14
Ah, didn't see that on the other thread.

Do you know whether there's still an issue with streaming AAC files that have the metadata at the end?

pkfox
2014-10-04, 02:26
Since you can now play AAC streams (as detailed in another thread) I'm assuming transcoding is OK so the problem would seem to be the AAC file.

Do these files have any embedded video / images ?

Hi again, the files were created be streamripper and ripped from radioio.com

pkfox
2014-10-04, 02:28
Is your server not able to transcode? Transporter doesn't support AAC so it needs to be transcoded

Thanks for answering I see bpa has pointed you to the other thread

bpa
2014-10-04, 03:41
Hi again, the files were created be streamripper and ripped from radioio.com

OK - need more info as the AAC file can be in a number of formats (e.g. MPEG4, RTS)

Can you run the faad command on the file to see what faad thinks the file is. e.g.
from shell prompt

cd <LMSdirectory with faad which ends with Bin/arm-linux/>
./faad -i <full path to AAC file which doesn't play>

pkfox
2014-10-04, 06:40
OK - need more info as the AAC file can be in a number of formats (e.g. MPEG4, RTS)

Can you run the faad command on the file to see what faad thinks the file is. e.g.
from shell prompt

cd <LMSdirectory with faad which ends with Bin/arm-linux/>
./faad -i <full path to AAC file which doesn't play>

Hi, the only output I got was RAW

bpa
2014-10-04, 06:53
Hi, the only output I got was RAW

That means the audio is not compressed and probably was saved in WAV format. If it is in WAV and if you don't have the extension WAV on the file LMS will not decode it properly.

edit:

When playing file with VLC, what does VLC say the file is under Tools / Codec Info ?

pkfox
2014-10-04, 08:36
That means the audio is not compressed and probably was saved in WAV format. If it is in WAV and if you don't have the extension WAV on the file LMS will not decode it properly.

edit:

When playing file with VLC, what does VLC say the file is under Tools / Codec Info ?

So if I rename it to .wav it might work ?

bpa
2014-10-04, 08:53
So if I rename it to .wav it might work ?

That's the theory - it depends on whether the file is actually in WAV format - faad is saying, it thinks the file is not AAC in MPEG4 or RTS format. For example, faad will say RAW if file is in Flac or WMA - so I think faad can only say for sure if it not an AAC/ALAC format Since VLC can play the file the VLC Tool/Codec info should be more accurate.

pkfox
2014-10-05, 00:47
That's the theory - it depends on whether the file is actually in WAV format - faad is saying, it thinks the file is not AAC in MPEG4 or RTS format. For example, faad will say RAW if file is in Flac or WMA - so I think Flac can only say for sure if it not an AAC/ALAC format Since VLC can play the file the VLC Tool/Codec info should be more accurate.

OK thanks I'll look at vlc and see what it can tell me. BTW I tried renaming and no joy.

pkfox
2014-10-06, 04:06
That's the theory - it depends on whether the file is actually in WAV format - faad is saying, it thinks the file is not AAC in MPEG4 or RTS format. For example, faad will say RAW if file is in Flac or WMA - so I think faad can only say for sure if it not an AAC/ALAC format Since VLC can play the file the VLC Tool/Codec info should be more accurate.

Hi there,VLC codec info says the file is in mp4a so presumably I can rename it with .mp4a extension ?

Edit

Tried that didn't work - why is all this so complicated ? ;-)

bpa
2014-10-06, 04:47
Tried that didn't work - why is all this so complicated ? ;-)

It sounds like streamripper created a non standard AAC file.

faad can handle standard AAC files in all standard formats (i.e RTS and MPEG4) . It sounds like stream ripper has created a non standard file probably just a byte for byte copy of AAC stream stripped of http protocol with no file header i.e. at intervals in the stream the stream format is inserted. This is the quick and dirty way of making internet stream copies. LMS and faad expects an audio file to have a header at the start unless it is a stream where the info is given in http headers.

I suggest see if you can use VLC to convert the streamripper file into proper standard files.

pkfox
2014-10-06, 07:05
It sounds like streamripper created a non standard AAC file.

faad can handle standard AAC files in all standard formats (i.e RTS and MPEG4) . It sounds like stream ripper has created a non standard file probably just a byte for byte copy of AAC stream stripped of http protocol with no file header i.e. at intervals in the stream the stream format is inserted. This is the quick and dirty way of making internet stream copies. LMS and faad expects an audio file to have a header at the start unless it is a stream where the info is given in http headers.

I suggest see if you can use VLC to convert the streamripper file into proper standard files.

Don't think VLC has conversion tools except for messing with effects , all this started because my brother in law runs a radio programme once a week in Australia and I record and save it as one big file - it's ok with his site as it is mp3 stream it's only a problem with radioio but maybe that's why they do it. Not to worry thanks very much for your help ( do you do this for a living as you seem very knowledgeable ? )

bpa
2014-10-06, 07:22
Don't think VLC has conversion tools except for messing with effects

yes it does - under Media menu - there is "convert/save" - add the file then click "converr save" and then after filling in destination name etc. select the "Audio Flac" profile and convert.

pkfox
2014-10-06, 07:52
yes it does - under Media menu - there is "convert/save" - add the file then click "converr save" and then after filling in destination name etc. select the "Audio Flac" profile and convert.

Whoah - that worked thanks