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From: Aditi on 2 Feb 2010 17:56
Hi All,

I want to create and play a G726 (16 kbps) encoded .wav file with
Windows Media Player (WMP).
I have modified the normal wave header to allow for different G726
codes (0x0045 - ITU G726, 0x0064 - APICOM G726, 0x0085 - Data Fusion
G726). When I play the wave file after modifying it as above, the WMP
gives an error message saying "One or more codecs required to play the
file". I tried downloading and installing "Sharp G.726 codec". Still
the modified .wav file doesn't work with WMP.

Do we have to add any extra portion to the WAVE header for non-PCM
formats
( I found a link for the mu-law format). If so, could some one tell me
the header portion
for G726. Also how would WMP recognize at which bit rate I have
encoded the wavefile?

Could you tell me which G726 codec download works well with WMP?
And also which file compression code (Format tag number) does the G726
use?

If someone could provide me with a sample g726 coded/decoded .wav file
or
a g726 encoded .wav file which can be played in WMP, it would help me
a lot


Thank you,
Aditi.
From: Richard Dobson on 2 Feb 2010 19:21
On 02/02/2010 22:56, Aditi wrote:
> Hi All,
>
> I want to create and play a G726 (16 kbps) encoded .wav file with
....
You may be out of luck; Media Player requires files in
WAVEFORMATEXTENSIBLE (WAVEX) for just about everything these days (even
for plain 24bit PCM), and probably a WAVEX version of G726 never got
defined (it's not in Microsoft's header file mmreg.h, at least). It may
be worth Googling "G726 + WAVEFORMATEXTENSIBLE" in case it finds
something useful. Ostensibly it requires both a format to be defined,
and a custom codec written to support it. As you indicate, it is
something of a polyglot "standard", whose time may just have passed. May
be simpler just to find some 3rd party software that can decode to a
standard PCM file. Which leaves the question, why bother to ~create~ it
in that format anyway?

Richard Dobson


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