AC3 to WAV?

[killerteengohan]

Option I picked for the .WAV was "PCM signed 16 bit, stereo" there were no other ways to configure it other than PCM signed and unsigned, 8, 16, 24, 32, 64 bits, and stereo or mono. I never used the IEEE float signed settings before.

[Cornucopia]

If you did a decode to integer of the WAV source and a decode to integer of the FLAC file, inverted the phase/polarity of one (but not the other), and mixed down, you will see that there is NO difference!

As detmek said, there may be some EXTREMELY MINISCULE differences if you do FP<->INT conversion (on 1 or both of the files). Regardless, you shouldn't base your idea of what is the same by a visual thumbnail overview. The only proper way to compare is to do a proper decode+diff.

Honestly, you should move on...

Scott

[killerteengohan]

I tried saving the AC3 as .FLAC in a different program (Sony Vegas Pro 13) and it looks like it varies even more than before now.

https://forum.videohelp.com/images/imgfiles/dHRQ4FJ.png

original AC3 on bottom, synced FLAC on top.

[killerteengohan]

I cant say I can audibly hear a difference from the 2 tracks, but isnt the FLAC losing or gaining audio waves in certain areas? Doesn't that mean data or sound isnt the same in some parts according to those wave lines?

[newpball]

I cant say I can audibly hear a difference from the 2 tracks, but isnt the FLAC losing or gaining audio waves in certain areas? Doesn't that mean data or sound isnt the same in some parts according to those wave lines?

Are you or are you not familiar with the concept of lossless compression?

[killerteengohan]

I cant say I can audibly hear a difference from the 2 tracks, but isnt the FLAC losing or gaining audio waves in certain areas? Doesn't that mean data or sound isnt the same in some parts according to those wave lines?

Are you or are you not familiar with the concept of lossless compression?

I am.

Have you looked at the picture I gave which shows it as not being the same like the lossless WAV file is?

If it decompresses when opened in an audio editor like someone said before then it should look the same as the original file I would think. The .WAV file is the same.

[Detmek]

FLAC compresses losslessly if your source is in integer format. If your source is floating point FLAC needs to convert floating point into integer and then compress the file. Float - integer converson produces rounding errors. Also, if you encode into 16-bit FLAC, dither is usually involved. This will create a file that is mathematically different from original.

In order to get exactly the same lossless file as your source in Audacity or some other audio editor that internally works in 32-float mode you need to export your file as 32-bit floating point WAV. Exporting in any other integer format will produce file that is mathematically different from original. You can do a null test to check for differences, as Cornucopia said.