simple question: pcm 2 wav

[dani82]

i just finish encoding this dvd, and found out the audio is pcm and not ac3; i know how to convert an ac3 2 wav, but not an pcm? so what do i do?

[pacohaas]

try just renaming it to .wav

[DSPguru]

why do you need to convert it to wav ? don't you want to convert it ot mp3/ogg ?

anyway,
you can use BeSweet to transcode pcm to wav/mp2/mp3/ogg/ac3.

[dani82]

besweet doesn't work, the audio just comes out distorted, so distorted, that it is just static; it's just same as renaming it to .wav (won't even play in winamp); any more help would be very appreciate.


why not mp3/ogg?

vcd

[DSPguru]

sounds like a 20/24bits to me.

i never found the time to check this thing out, but i know LigH did.

[LigH]

Hi dani82,

a little while ago I wrote a tool called "Twen" which shall be able to convert 20bit DVD-PCM to a 16bit or 24bit WAV. You shall be able to find it as attachment of an article in some forum here, or also in the german forum...

But before you try to use it blindly, I'd be interested in details about that. I know that SmartRipper shall be able to detect in Movie Mode / Stream processing, if the audio stream - in case of PCM - has 20 bits; and this format is horribly complicated, it has a strangely interleaved structure.

If you would like, you could send me a sample. For example, you could try to create a multivolume WinRAR archive of that PCM file with a volume size of around 500-700 KB, and send me the first volume file only. Send me a PM if you agree, or find my mail address in HeadAC3he or BeSweet.

[Amerzone]

Well, the pcm --> wav transcoding does not work for me either. Even if the wav file plays in WiMP, all I get is a high-pitch static noise... :( And, as far as I can tell, the pcm is indeed 48k, 16-bit, 2ch (info is shown in the filename of the pcm ripped from DVD Decrypter and of the wav file ripped from SmartRipper). Check the thread http://forum.doom9.org/showthread.php?s=&threadid=36207 in the Decrypting section for more details.

In that thread I claim that this might be a bug of BS, but frankly speaking I'm not quite sure; this could be a bug of DVDDec, who knows?

BeSweet command line (I'm currently using v1.4)

"C:\Audio\BeSweet\BeSweet.exe" -core( -input "h:\finalcut\VIDEO_TS\VTS_02_1 - 0xA0 - Audio - LPCM - 2ch - 48kHz - 16bit.pcm" -output "h:\finalcut\VIDEO_TS\intro.wav" -2ch -logfile "C:\AUDIO\BESWEET\BeSweet.log" )

File sizes:

WAV ripped by Smartripper = 12,211,244 bytes (plays fine)
PCM ripped by DVD Decrypter = 12,211,200 bytes (does not play at all)
WAV transcoded by BeSweet from PCM = 12,211,244 bytes (plays, but noisy)

[kheops]

hi,

if you don't want to install a big soft (like cool edit or soundforge), goldwave should be able to do what you want

drag n drop your pcm in the main window, write here the infos it gives (it may help) and save it to wav

hxxp://www.goldwave.com

+++

[Amerzone]

I checked the PCM file that DVD Decrypter produces once more, this time with Cool Edit Pro 2.0 When I open it, Cool Edit asks for some help on how the data is formatted. If I choose 16-bit Intel PCM (LSB, MSB) then I get just awful noise; on the contrary, if I open it as 16-bit Motorola PCM (LSB, MSB), then it plays fine ;) And, of course, Cool Edit can save it as wav file, adding these 44 header bytes. Any idea why this cannot be done with BeSweet?

[DSPguru]

Originally posted by Amerzone
Any idea why this cannot be done with BeSweet? i will add this feature.

[LigH]

@ dani82:

I received the file, thanks. As far as I could see, this is definitely a 16bit file. And it is distorted. But very strangely: Each regular distance (0.0105 s), there is one byte either missing or inserted. It rather looks like this audio file was grabbed or demuxed incorrectly. So even "Twen" won't help here.

Sorry, no chance.

[DSPguru]

use BeSweet v1.5b1 with -core( -be )

(a new switch for handling BigEndian pcm)

[Amerzone]

Well done DSPguru, the new switch works just fine! :p

[DSPguru]

great :)

[dani82]

it's a lost cause (for me).

i try everything that you all recommend, but at the end; all i get is the same result: distortion.

i should have guess something was wrong when flask didn't find any audio tracks, even though i never use it to encode the audio part.

i know, i know, i should switch to something better than flask, but my computer is a celeron 500, and every other program and format, just takes to long, i really should upgrade.

[LigH]

Just once again, as I wrote: This audio stream is corrupt. There are blocks of always the same size - one each is okay, the next one is shifted by one byte. If this was caused by inserted bytes, it could be fixed (but at which effort?); if it was caused by lost bytes, they are lost forever.

I somehow missed which DVD title it was. Could you please publish that information, as exactly as possible? It may help others to get this DVD and check this issue.