On Mon, Jan 12, 2009 at 16:15, Karl Fife <[email protected]> wrote: > QUESTION: Who's in the wrong: > > I recently saw an example of a u-law file with a metadata header on the > file. > The asterisk playback function 'PLAYED' the ascii header values as if they > were audio data, creating an audible 'click'. > > After realizing the click was coming from metadata (and fixing it), I became > curious: > > Which is 'correct? In other words: > > 1. Is it considered incorrect to ever include metadata on a u-law formatted > file? > or > 2. Is it considered incorrect for a playback engine to fail to check for > metadata headers before playback? > or > 3. Is it unspecified, and therefore considered incorrect for someone (ME) to > FEED a u-law stream into any playback engine without FIRST making sure that > somebody's two-bit application didn't tack on an unsolicited header? :-) > > In other words, should case 1 or 2 be considered a software defect?
No, it is not a defect. You need to distinguish between the file format and audio codec. They are independent of each other. You can store ULAW in a WAV file. The default asterisk sounds (.g729, .ulaw, .alaw) are raw audio files, thus there is no header. If Asterisk is expecting a raw format file, it will playback the entire "contents." If I save a WAV format file encoded in ulaw, name the file .ulaw, and then play it back in Asterisk, the exact scenario you describe happens. _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
