Beginning of MP3 file truncated on decode

[mhakman]

When I convert some MP3 files (384 kbps free format) to wave (or other formats) the beginning of each file is missing in corresponding output file. About 0.5 seconds is missing and the first 0.05 seconds after that is somewhat distorted as compared with the original. The same mp3 file dropped into Audacity or decoded directly by Lame is ok. Also, some other files that decode in Lame without problems yield 0-length wave file when decoded with dbpowerAMP. What can be wrong?

Thanks/Mikael

[LtData]

Re: Beginning of MP3 file truncated on decode

Are you running any DSP effects? Are you using dMC r11.5?

[Bill41]

Re: Beginning of MP3 file truncated on decode

When I convert some MP3 files (384 kbps free format) to wave (or other formats) the beginning of each file is missing in corresponding output file. About 0.5 seconds is missing and the first 0.05 seconds after that is somewhat distorted as compared with the original. The same mp3 file dropped into Audacity or decoded directly by Lame is ok. Also, some other files that decode in Lame without problems yield 0-length wave file when decoded with dbpowerAMP. What can be wrong?

Thanks/Mikael

dMC has problems with some 384 kbps free format files. Use Speek's MAD frontend for these files. http://members.home.nl/w.speek/mad_frontend.htm
Works for me.
Bill

Or maybe a better way to phrase it "some of my free format files" :smile2:

[Spoon]

Re: Beginning of MP3 file truncated on decode

R12 (alpha) does not...

[mhakman]

Re: Beginning of MP3 file truncated on decode

Thanks all for help so far.

R12 (alpha) does not...

I tried R12 (alpha) and it handles correctly some of the files that R11.5 truncated. Some other files are now not handled at all. For these dMC works for about 3 min showing 1:30 hour to complete and then I get only 1 MB garbage. I could send you one of the files if you need it (12 MB).

For all of my 384 kbps files, dMC popup in Explorer shows “Lame 3.91a; Variable Bit Rate 375 kbps (Free-Format) “. I think the files are 384 CBR. Also there is no “Convert to” item in the right-click popup.

dMC has problems with some 384 kbps free format files. Use Speek's MAD frontend for these files...

I’m using dMC primarily to convert MP3 to FLAC and vice versa which automatically transfers all the tagging between formats. I have no problem using Lame or MAD frontend to decode to WAV and then using FLAC frontend to encode to FLAC (or vice versa). However then I would need to edit (add) the tags manually to each destination file which is error prone and boring if you have more than few files to convert.

Or maybe a better way to phrase it "some of my free format files" :smile2:

I suppose that you are referring to the fact that 384 CBR isn’t a part of the formal MP3 specification or a part of MPEG1 Audio Level III specification to be precise or a part of ISO IEC 11172-3 standard to be exhaustively precise, which limits the bandwidth when specified to 320 kbps. Therefore it could be argued on both technical and legal grounds whether 384 CBS is in fact MP3 or only MP3-like encoding. Using encoders that do not follow exactly the original Fraunhofer patent, such as Lame (LAME Ain't an Mp3 Encoder) but produce files that may be decoded by standard conforming MP3 decoders adds to this arguing opportunity. However, the standard allows for free format bit rates and it doesn’t specify how the encoding is done, only its results.

Would I use expression “some of my free format files” instead of “some MP3 files” (“my” being implicit) then not all readers of this topic would immediately understand what kind of encoding I’m talking about. I can only hope that you aren’t too disturbed by this trading of understanding for exactness. Thanks all for help so far.

[Bill41]

Re: Beginning of MP3 file truncated on decode

"I’m using dMC primarily to convert MP3 to FLAC and vice versa which automatically transfers all the tagging between formats. I have no problem using Lame or MAD frontend to decode to WAV and then using FLAC frontend to encode to FLAC (or vice versa). However then I would need to edit (add) the tags manually to each destination file which is error prone and boring if you have more than few files to convert."



Sounds like you got your files from the same place I got mine,Allofmp3.Use Speek's multi frontend to transcode,http://members.home.nl/w.speek/multi.htm, to almost any format that you have the codec for and it will write the tags also. You just need the tag.exe from Case and for all of my other converting needs, I do use dMC and play my music with Dap.

[Spoon]

Re: Beginning of MP3 file truncated on decode

> I could send you one of the files if you need it (12 MB).

Please:

http://www.dbpoweramp.com/email.htm

[mhakman]

Re: Beginning of MP3 file truncated on decode

Please:

http://www.dbpoweramp.com/email.htm

A file has been sent.

Thanks/Mikael

[mhakman]

Re: Beginning of MP3 file truncated on decode

Sounds like you got your files from the same place I got mine,Allofmp3.Use Speek's multi frontend to transcode,http://members.home.nl/w.speek/multi.htm, to almost any format that you have the codec for and it will write the tags also. You just need the tag.exe from Case and for all of my other converting needs, I do use dMC and play my music with Dap.

Many thanks for advice and links. It works as you describe but it would still be nice to have dMC handling these files too. BTW, you are very observant, yes, I do buy some of my music there :D Normally I prefer lossless encodings but as not all music available electronically is available in lossless format then 384 CBR is the next best thing.

Regards/Mikael

[Bill41]

Re: Beginning of MP3 file truncated on decode

Many thanks for advice and links. It works as you describe but it would still be nice to have dMC handling these files too.

Regards/Mikael

I agree. :smile2:

Bill

[Spoon]

Re: Beginning of MP3 file truncated on decode

Got the file thanks, will look when get a chance (I think I know what is happening, or free-format it is looking for bitrates 384kbps and above, your file has a bitrate below that).

[Spoon]

Re: Beginning of MP3 file truncated on decode

I have fixed this (was an error in the files, which was causing to loose sync and freeformat works so that it was resyncing on non propper mp3 frames).

Check out the next r12 alpha in about 1 week time.