Need Help Converting AAC to MP4

[Jason84]

I tried converting some AACs to m4a and I wound up with file sizes roughly twice as large as the originals.

-I selected to convert to m4a Nero (AAC)
-using neroAacEnc.exe as the encoder
-no forced profile

Am I doing this correctly? I thought this process was just changing the container (which I only vaguely understand), so why all the encoding time and much bigger file sizes?

I used the two following threads to try to figure things out, but it seems I'm doing something wrong here:

http://forum.dbpoweramp.com/showthread.php?26788-Batch-converter-aac-to-m4a-not-working

http://forum.dbpoweramp.com/showthread.php?24729-I-have-tried-several-times-to-add-the-Nero-AAC-encoder...&p=115468&viewfull=1*post115468

I really appreciate any help, thanks

[Spoon]

Re: Need Help Converting AAC to MP4

Converting t m4a Nero (AAC) actually decodes and reencodes.

[Jason84]

Re: Need Help Converting AAC to MP4

Converting t m4a Nero (AAC) actually decodes and reencodes.

I figured that's what was happening. Is there a way to go aac > m4a without decoding and reencoding?

[Jason84]

Re: Need Help Converting AAC to MP4

I should also add that I have hundreds of such conversions in a folder structure I would like to retain, so file by file, command line solutions will not work.

[Spoon]

Re: Need Help Converting AAC to MP4

http://codecs.dbpoweramp.com/codecs-new/dBpoweramp-Codec-m4a-utilities.exe

This can shift aac in and out of the m4a container.

[Jason84]

Re: Need Help Converting AAC to MP4

Thanks so much. One AAC file coded as ADTS didn't convert. Is there a way to do this?

[Spoon]

Re: Need Help Converting AAC to MP4

Not with our tools.