HydrogenAudio

Lossy Audio Compression => AAC => AAC - General => Topic started by: AlexQc on 2017-10-18 03:54:29

Title: qaac under EAC quations
Post by: AlexQc on 2017-10-18 03:54:29
Hello,

After reading some (contradicting) tutorials on using qaac with EAC, I have some questions...

Some tutorials say to use qaac64.exe some say to use refalac64.exe (or their 32-bit counterparts). Both seems to work... Is there a "better" entry point?

Why some tutorials tell to uncheck the "Use CRC check" option and some other don't? Is it useless?

Thanks for your input!
Title: Re: qaac under EAC quations
Post by: Case on 2017-10-22 15:56:09
Some tutorials say to use qaac64.exe some say to use refalac64.exe (or their 32-bit counterparts). Both seems to work... Is there a "better" entry point?
I recall the reference ALAC implementation was slow. I also believed that iTunes uses highly optimized code allowing it to be faster than refalac. But I just benchmarked qaac vs refalac and qaac64 vs refalac64 and refalac was noticeably faster each time.

Why some tutorials tell to uncheck the "Use CRC check" option and some other don't? Is it useless?
The CRC setting only enables the use of command line parameters specified inside %c...%c block. If that optional feature isn't utilized on the command line the checkbox has no effect.

One could use it with LAME for example with command line string "%c-p%c". That way when CRC checkbox is ticked the "-p" parameter is active telling the encoder to write checksum to frames.
Title: Re: qaac under EAC quations
Post by: AlexQc on 2017-10-23 14:12:52
So refalac can be used to encode AAC and not just ALAC??

What's the difference between  qaac.exe and refalac.exe? Don't the resulting files are identical?

Thanks!
Title: Re: qaac under EAC quations
Post by: Case on 2017-10-23 14:54:21
Refalac is short for reference ALAC. It's an ALAC encoder based on Apple's reference source code. It can not encode AAC but it's a standalone program not requiring any additional dlls or installed programs.

Qaac is a command line frontend for iTunes' libraries. It can encode both AAC and ALAC but it requires having iTunes installed (or its libraries extracted to a directory it can find them from).

The produced ALAC files will not be identical but ALAC is a lossless codec and both encoders will produce files that decode perfectly to the original source file.

If you have the drive space I'd recommend not encoding to AAC with EAC. CD ripping is slow and most people don't want to do it several times. If you use a lossless codec such as ALAC you'll have a perfect copy that can be later reconverted quickly to a different lossless format. And you can quickly make AAC versions for special uses as required.