Re: Issue of Mpeg4 Audio (Newbe)
Re: Issue of Mpeg4 Audio (Newbe)
- Subject: Re: Issue of Mpeg4 Audio (Newbe)
- From: William Stewart <email@hidden>
- Date: Wed, 6 Jul 2005 12:00:51 -0700
The AudioFile APIs that we provide in Mac OS X will play back (and
create) these files in Tiger. So, you could take the AudioFileTools
and use those tools (afconvert, afplay, etc) to read and write these
files
Bill
On 06/07/2005, at 3:17 AM, ranjeet gupta wrote:
On Wed, 06 Jul 2005 Stephen Davis wrote :
>Ranjeet,
>> I have the issue on the m4a (Mpeg 4 Audio), The basic thing what
>> I have to do is that I have to read the m4a audio and play back,
>>
>> The First basic thing I did is that, I copied all the data into
>>the
>> new file i.e abcd.m4a as the copy_abcd.m4a and then playing the
>> file into the foobar player, I observaed that the copied file
>> i.e copy_abcd.m4a is playing fine,
>>
>> Now what I have to do is I have to play the file by skipping
>> some amount of the data, (Forward Skipping)
>>
>> so i skipped some amount of data (Here I skipped in terms of
bytes),
>> and then made the file again names as the skipped_abcd.m4a, Now
when
>> I play this file into the foobar then i see that it says about the
>> error, that it cannot play,
>MPEG-4 files are highly structured so you can't just hand a
random >set of bytes from such a file to a decoder and expect it
to work.
yes, I came to know As i was going through the ISO/SC29 Refrence
Software Guide Version Is Dated 2000-08-08, For this I have been
given the source code for this, Is there any API present In this
Software guide which tells about how to skip the Audio of the
MP4 ?
>> Again searched for the soulution of this, I came to know that
>> and read the site, and worked accoreding to it,
>> http://www.dv.co.yu/mpgscript/mpeghdr.htm
>This document describes MPEG-1 audio data. The MPEG-4 file format
>is drastically different than this format.
Thanks for giving your comment as I was also thinking the
same but was not sure.
>
>I would suggest looking for ISO document "ISO/IEC 14496-3:2001"
and >its siblings and going from there.
I searched for the spec but it is payed one :-(
well I have ISO/SC29 Refrence Software guide so please do guide me
Thanks
Ranjeet
>stephen
>_______________________________________________
>Do not post admin requests to the list. They will be ignored.
>Coreaudio-api mailing list (email@hidden)
>Help/Unsubscribe/Update your Subscription:
40rediffmail.com
>
>This email sent to email@hidden
_______________________________________________
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