[Mp4-tech] Re: parsing AAC-LD LATM stream

[Ralph Sperschneider]

Yifat Kuttner wrote:
>
> Hi
>
> I'm trying to parse an AAC-LD (LATM) stream.
>
> My goal is to figure the total length of the frame - header and 
> payload, and find the first byte of the payload.
>

The total length of the frame is given in the AudioSyncStream() by means 
of the audioMuxLenghtBytes.
> Unfortunately my reference code is missing the LATM parsing functions,
>
> So after reading the *AudioMuxElement *info, I'm not sure what to do 
> with it.
>
> - Packet total length: 160 bytes.
>
> - MuxSlotLengthBytes is called twice. Get 72 and 13.
>

That sounds odd. How do you come to this - you stated above that you 
would not have LATM parsing functions.
>    1. Does the payload starts where the *AudioMuxElement *finished
>       (bit 69)?
>

The payload is part of the AudioMuxElement(). This is obvious from its 
specification in ISO/IEC14496-3.
Ralph
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Dipl.-Ing. Ralph Sperschneider  | Phone: +49 9131 776 344
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