• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: writing m4a problems continued, II
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: writing m4a problems continued, II


  • Subject: Re: writing m4a problems continued, II
  • From: William Stewart <email@hidden>
  • Date: Tue, 10 May 2005 10:54:08 -0700

John

If you run the afconvert tool in the SDK, does this write a valid m4a file:

% afconvert /System/Library/Sounds/Submarine.aiff /tmp/tmp.m4a -f m4af -d alac -v
% afinfo /tmp/tmp.m4a


Bill

On 09/05/2005, at 6:40 PM, john wrote:

Hi Doug,

I seemed to have missed that it appears the AudioFile which is created is 0 bytes. I looked at it in HexEditor.app and there is nothing, totally blank. I would expect it to be initialised with at least a header, is this not so?

I tried AudioFileCreate() and AudioFileInitialise(), same result.

-- John



John,

That looks like an error code from the MP4 audio file component ... hm, a MP4DataInformationAtom has a nil dataReference atom pointer.

When writing .mp4/.m4a, the component requires that you start with packet 0 and write packets sequentially from there. What packet number are you writing when this fails? What packet numbers have you written previously?

Doug

_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list      (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden


--
mailto:email@hidden
tel: +1 408 974 4056
________________________________________________________________________ __
"Much human ingenuity has gone into finding the ultimate Before.
The current state of knowledge can be summarized thus:
In the beginning, there was nothing, which exploded" - Terry Pratchett
________________________________________________________________________ __


_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list      (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden


References: 
 >writing m4a problems continued (From: john <email@hidden>)
 >Re: writing m4a problems continued (From: Doug Wyatt <email@hidden>)
 >Re: writing m4a problems continued, II (From: john <email@hidden>)

  • Prev by Date: Re: Combining AUHAL input and an AudioConverter
  • Next by Date: Re: Mono plugs (was: AUBase preset handling change)
  • Previous by thread: Re: writing m4a problems continued, II
  • Next by thread: How to cut silence away from the beginning of output signal
  • Index(es):
    • Date
    • Thread