Why use m4a Optimize and RTP hint?

[mbone@kiva.net]

I have a library of files in Apple Lossless and AAC formats, and I'm wondering what applications benefit from using m4a Optimize on the files, and also when to use the RTP hint option. Is it for iTunes streaming only, or Apple TV, or other devices as well? Is it necessary to optimize Apple Lossless files, or just AAC files? I'm just wondering because if it's something I may use in the future, I'd rather go ahead and optimize the files now.

Also, iTunes adds a tag called iTunSMPB as it converts from Lossless to AAC. I believe it has something to do with gapless playback. Anyone know if it's possible to create this tag outside of iTunes for the Apple Lossless files that were created using dMC to convert from FLAC?

[Spoon]

Re: Why use m4a Optimize and RTP hint?

Only the mentioned devices require the hint track.

[mbone@kiva.net]

Re: Why use m4a Optimize and RTP hint?

Thanks.

Do you know if AAC files created by iTunes have the optimization and RTP hints, or if I would need to add them using dMC? Is there a way to tell it it's there by analyzing the file somehow?

[Spoon]

Re: Why use m4a Optimize and RTP hint?

The Apple created files would already have them.

[mbone@kiva.net]

Re: Why use m4a Optimize and RTP hint?

I ran m4a optimize on my Apple Lossless files, and I found that 29 files cause errors. The box with the "Send to Microsoft" button comes up with the message "mp4creator.exe has encountered a problem & needs to close."

When I remove these files from the batch list, m4a optimize runs without error. I can tell m4a optimize didn't do anything to the files when the errors occurred because the modified date didn't change.

I can't find anything wrong with these 29 files. They play just fine and don't have any audible problems. It doesn't affect all songs on any particular album.

The ALAC files were created from FLAC files using dMC Batch Converter. The FLAC files were ripped from CD using CD Ripper. I'm using dMC v13.3 and m4a R8 with the latest Nero Digital files, but the FLAC files were ripped using dMC v13.1.

What more can I do to troubleshoot?

[Spoon]

Re: Why use m4a Optimize and RTP hint?

mp4creater is an outside program, we cannot change it.

[mbone@kiva.net]

Re: Why use m4a Optimize and RTP hint?

I understand. Is there someone who maintains the program that I could go to for help or advice?

[Spoon]

Re: Why use m4a Optimize and RTP hint?

It was part of mp4 tools which AFAIK is now no longer developed (not since a few years ago).

[mbone@kiva.net]

Re: Why use m4a Optimize and RTP hint?

For what it's worth, I did some more testing after reverting back to dMC 13.1, and found that m4a optimize ran successfully on 21 of the 29 files that it crashed on with 13.3.