Conversion to 320k CBR = free-format?

[nab128]

Using r12.3 any file I convert to Lame mp3 320k CBR, now I have my infotags working, I can see that they all have the free-format bit set. Converting to 256k or below it is not set. Many times the bitrate in infotag shows up as 322k, 324k etc even though the Encoder Settings show "Constant Bit Rate 320 kbps (Insane)"

The same infotag info appears if I convert to 320k free format. This makes me think I don't have true CBR files after conversion. What is the difference between 320k CBR and 320k free-format anyway?

[Spoon]

Re: Conversion to 320k CBR = free-format?

It is just our detection of freeformat files, if they say they are encoded as 320 insane, ignore the freeformat bit.

[nab128]

Re: Conversion to 320k CBR = free-format?

OK thanks Spoon

Why do some tracks show 322k, 325k etc as the bitrate? This makes me nervous as the rest of our 320k files do not have the free format bit and always show 320k. This tells me there is a technical difference in the files converted by dMC which could cause issues in the future.

[Spoon]

Re: Conversion to 320k CBR = free-format?

If the files play fine in say Windows Media Player, you will not get any issues (WMP cannot play freeformat).

[bhoar]

Re: Conversion to 320k CBR = free-format?

Why do some tracks show 322k, 325k etc as the bitrate? This makes me nervous as the rest of our 320k files do not have the free format bit and always show 320k. This tells me there is a technical difference in the files converted by dMC which could cause issues in the future.

Not knowing which plug-in is showing the > 320kbps bitrate, I can see two reasons for this:

1. A large amount of metadata or embedded album art might cause a (badly or simplistically written) plug-in to show a bitrate that is higher than what it should for the actual audio data which is 320kbps or less.

2. If the encoder did not use the strictISO option (or the version of lame used does not have it set as a default), which forbids the possibility of slightly exceeding 320kbps in non-freeformat mode (I think strictISO is what it is called), then there might actually be more than 320kbps of data due to the combination of full 320kbps frames *plus* the bit-reservoir being used.

Spoon?

-brendan

[nab128]

Re: Conversion to 320k CBR = free-format?

Its the dbPowerAmp infotip that shows the high bitrate figures but I think its a bit buggy because I now have a CBR file that shows VBR in the infotip.

I have also found that whatever value I set for the mp3 decoder bit depth in the advanced options will show up as the bit depth for all existing mp3 files in the infotip.

[Spoon]

Re: Conversion to 320k CBR = free-format?

mp3 files do not have a bit depth, internally it is floating point when decoded.

[davidmneves]

Re: Conversion to 320k CBR = free-format?

Hi everyone.

I have the same problem, the MP3 generated with 320 Kbps settings are UNPLAYABLE
in my card audio MP3 (Original Honda Civic 2013 audio wiht USB input) and,
IMHO, this IS A BUG in DBPowerAmp.

Why?
Because converting directly with LAME.EXE in command line or with the "CLI Encoder" plugin, is clear that the --freeformat IS CALLLED in "mp3 (Lame)" plugin, even that debug info of Lame shows nothing about:

"
Encoding To: mp3 (Lame)
Encoder Cmd Line: -b="320" -q="0" -channels="forced stereo" -crc="1" -force_iso="1"
"





So...
I create a CLI configuration that gives que desired quality and the files are CORRECTLY converted

[infile] [outfile] -cbr -b 320 -m s --nohist -q 0 --strictly-enforce-ISO -p

[Spoon]

Re: Conversion to 320k CBR = free-format?

Which version of dBpoweramp do you have?

In the dBpoweramp Configuration program (for r16: control center >> configuration 'advanced settings') enable the debug log, then convert one file at 320 kbps and after the debug log shows, look for the line:

Lame encoder settings:

This is the exact line which is passed to lame.exe, it is not altered in any way.