Forums

MPEG4 AAC LC Decoder

Started by deepa_r06 June 13, 2005
Hi All,

     I am in the process of porting the MPEG 4 to CCS(c55x). I am 
facing problems with the wrapper code. Can anybody help me? The decoder 
decodes only 2 frames. Is it because of cmd file?

Thanx in adv,

Deepa
	
Hi Tony,

      Thanks for the reply. Few header files such as MP4Movies.h etc
have few functions for which the definition is hidden(I am working on
3GPP Code for MPEG4 AAC+),because of which I am not able to port the
code as such onto OMAP. One more thing, I need to know how to write the
header information (like ADIF/ADTS formats). I am struck up with that.
Can you please help?

Thanx for the info on OMAP Paging.

" Never let yesterday's disappointments Overshadow tomorrow's dreams . .
." 
 
Cheers
 
Deepa

-----Original Message-----
From: Francis, Tony [mailto:tonyf@tony...] 
Sent: Tuesday, June 14, 2005 6:07 PM
To: deepa_r06
Subject: RE: [audiodsp] MPEG4 AAC LC Decoder

Hi Deepa,

 OMAP uses one among the versions of 55x and paging is in OMAP as well.
You will have issue in porting with paging only if you are using large
static arrays which exceeds the page boundaries. 

 I didn't quiet get what you meant by header files not compatible to
OMAP. Can you clarify?

Regards,
Tony

-----Original Message-----
From: audiodsp@audi... [mailto:audiodsp@audi...] On
Behalf Of deepa_r06
Sent: Tuesday, June 14, 2005 1:00 PM
To: audiodsp@audi...
Subject: [audiodsp] MPEG4 AAC LC Decoder

Hi All,

       MPEG4 AAC Low Complexity Profile is the one i am working on. The 
code is running on MSVC++. I am porting the code onto OMAP5912. There 
are few memory related issues, like for Eg:On c55x stand alone there 
are something called PAGE concept(where each page is of 64k),but 
whereas in OMAP there is 160k of internal memory. Here there is no 
concept of PAGE. But my .map file still shows memory allocation as per 
PAGE. Has anybody come across such a problem?

       Basically I am facing problem with porting from VC++ to OMAP 
platform. There are few header files(like MP4Movies.h,ISOMovies.h)which 
are not compatible on OMAP.Why is this so? Moreover the definitions are 
hidden. How do I write my own header files so as to extract the header 
information and the raw data?Please help.

Thanx in adv,

Deepa
	
Hi Deepa,

ADIF and ADTS header sample code you can look into any of the public
domain codes (Best example is FAAD)

Basically ADIF header is just in the beginning of the stream and is used
for file storage and ADTS has a header which is in the beginning of
every frame and used in streaming.

 You can look into the ISO standards (13818 or 14496) for a description
on ADTS and ADIF. (I remember that there is a slight syntax difference
for ADIF and ADTS in 13818 and 14496 but cant remember the exact
difference).

Regards,
Tony

-----Original Message-----
From: Deepa [mailto:deepa@deep...] 
Sent: Tuesday, June 14, 2005 9:53 PM
To: Francis, Tony; audiodsp@audi...
Subject: RE: [audiodsp] MPEG4 AAC LC Decoder

Hi Tony,

      Thanks for the reply. Few header files such as MP4Movies.h etc
have few functions for which the definition is hidden(I am working on
3GPP Code for MPEG4 AAC+),because of which I am not able to port the
code as such onto OMAP. One more thing, I need to know how to write the
header information (like ADIF/ADTS formats). I am struck up with that.
Can you please help?

Thanx for the info on OMAP Paging.

" Never let yesterday's disappointments Overshadow tomorrow's dreams . .
." 
 
Cheers
 
Deepa

-----Original Message-----
From: Francis, Tony [mailto:tonyf@tony...] 
Sent: Tuesday, June 14, 2005 6:07 PM
To: deepa_r06
Subject: RE: [audiodsp] MPEG4 AAC LC Decoder

Hi Deepa,

 OMAP uses one among the versions of 55x and paging is in OMAP as well.
You will have issue in porting with paging only if you are using large
static arrays which exceeds the page boundaries. 

 I didn't quiet get what you meant by header files not compatible to
OMAP. Can you clarify?

Regards,
Tony

-----Original Message-----
From: audiodsp@audi... [mailto:audiodsp@audi...] On
Behalf Of deepa_r06
Sent: Tuesday, June 14, 2005 1:00 PM
To: audiodsp@audi...
Subject: [audiodsp] MPEG4 AAC LC Decoder

Hi All,

       MPEG4 AAC Low Complexity Profile is the one i am working on. The 
code is running on MSVC++. I am porting the code onto OMAP5912. There 
are few memory related issues, like for Eg:On c55x stand alone there 
are something called PAGE concept(where each page is of 64k),but 
whereas in OMAP there is 160k of internal memory. Here there is no 
concept of PAGE. But my .map file still shows memory allocation as per 
PAGE. Has anybody come across such a problem?

       Basically I am facing problem with porting from VC++ to OMAP 
platform. There are few header files(like MP4Movies.h,ISOMovies.h)which 
are not compatible on OMAP.Why is this so? Moreover the definitions are 
hidden. How do I write my own header files so as to extract the header 
information and the raw data?Please help.

Thanx in adv,

Deepa