diff options
Diffstat (limited to 'doc/READMEs/README.audio')
-rw-r--r-- | doc/READMEs/README.audio | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/doc/READMEs/README.audio b/doc/READMEs/README.audio new file mode 100644 index 0000000..7e2d7c9 --- /dev/null +++ b/doc/READMEs/README.audio @@ -0,0 +1,50 @@ +Why do I hear only noise from my first audio CD? + +You may have a byte swapping problem, try wodim -swab +but note that is is most unlikely that you need to use the -swab +option from wodim unless your input files are broken. +It makes more sense to find out why the inout files are not OK. + +wodim assumes Motorola/Network byte order (big-endian) on input +regardless of the byte order of the CD-Recorder. If wodim +encounters a .wav file, byte order is corrected to match the byte order +of the .wav file. + +wodim by default uses Track at once. This always gives 2 seconds +pause between two audio tracks and loweres the audio quality. + +For best audio CD quality, use wodim -dao (to write in Session At Once) +ot wodim -raw (to write in RAW mode). Note that there are a lot of drives +notably from Lite-ON that have defective firmware and will write defective +CDs if you use either TAO or SAO mode. In RAW mode, wodim has the +full control over the complete CD and the chance that the CD is OK +is much higher. + +The 2 seconds pause between two audio tracks is the CD ***standard*** + +The standard says: + Each track starts with 2 seconds of silence + followed by at least 4 seconds of audio data. + +For that reason the 2 second pause is generated by the CD-R drive in +Track at once (TAO) mode. + +CD's that have no pause between two tracks are illegal (compared to RED BOOK). +These illegal disks may be made with Disk At Once (DAO) only. +In DAO mode the writing software needs to send the 2 seconds pause as +binary zeroes and therefore is able to create illegal disks by +sending audio data instead. + +Some drives don't accept to write illegal disks even in SAO mode. +In this case, use the RAW mode. In RAW mode, the drive does not even +"know" what is going on and thus cannot prevent you from writing such +a disk. + +This audio data (the last two seconds of a track in this case) +however are part of the next track from viewing the TOC of the disk. +Digital Audio Extraction programs that work correctly (as intended by the +CD standard) split the content of a CD into files by including the +pre-gap (usually holding 2 seconds of pause) at the end of the previous +track. + +Eduard Bloch, based on documentation from Joerg Schilling |