[asterisk-users] file command with alaw file

[Pham Quy]

On Mon, 2010-05-17 at 17:49 +0700, Pham Quy wrote:
> On Mon, 2010-05-17 at 13:06 +0700, Pham Quy wrote:
> > hi all,
> > 
> > I install Asterisk 1.6 on Centos 5.2 (kernel 2.6.18-92.el5 #1 SMP Tue
> > Jun 10 18:51:06 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux) and do record
> > audio clip with mixmonitor() as alaw file (softphone is also configured
> > with alaw active only). Using file command i can get the following
> > information
> > 
> > 983006584-20100517-125002.alaw: RIFF (little-endian) data, WAVE audio,
> > ITU G.711 A-law, mono 8000 Hz
> > 
> > But when i install the same system on Centos 5.5 (kernel 2.6.18-92.el5
> > #1 SMP Tue Jun 10 18:51:06 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux) i
> > could get the same information with file command. File command
> > recognized alaw file as JPEG image:
> > 
> > 983006584-20100517-123825.alaw: JPEG image data
> > 
> > I guess i may miss something when i setup the new on on Centos 5.5, but
> > u dont know what it is. Anyone have idea about this?
> > 
> > please help.
> > 
> > Thanks in advance.
> > Quyps
> 
> I did check content of two alaw files (using a hex editor) generated
> from two aboves cases. For the one fromo CentOS 5.2, beginning bytes
> look likes : 
> 
> RIFF1^0.WAVEfmt........ at ...@.......fact.....^0.data.^0...
> 
> and the one from CentOS 5.5 
> 
> ......................RQVTV........XEMBAX............
> 
> It seem like the first one have some information about file format,
> which make our convert tool works correctly, and which the second one
> doesnt have.
> 
> Can you explain to me this different, and how can i get the information
> as the first one?
> 
> Thanks in advances,
> Quyps

This question have been asked for a while, I really need some help
here? 

Thanks in advance.
Quyps