Problem w. transcoding ogg into mp3: skips, truncated files

Lutz · Post by **Lutz** » Sun Sep 18, 2005 6:22 am

I've ripped many of my CDs into ogg files, with pretty high quality settings (e.g. 320kbps, etc.). Since I've just got an iPod (thank you for the cool sync feature!), I am trying to convert my files into mp3 format, using the preset 'Studio: ABR ~256kbps'. Unfortunately, MM 2.4.2.874 produces a lot of seriously damaged files in this setting.

1) When I select a batch of (ogg) files e.g. from a playlist, and convert them (Ctrl-Shift-C), most mp3 files get truncated at any random time - i.e. after 3 secs, in the middle of the song, or - most often - 1 sec before the actual end of the song. When I convert the exact same source file 1 by 1 - not as a batch - into mp3, this doesn't occur. What can I do to get MM to do batch transcoding properly?

2) Often the converted mp3s contain a small 'skipping' error, i.e. <1 second of music seems to have been ommitted by the mp3 encoder. The corresponding ogg sources are OK, at least from the listening experience. Any idea what that is?

Thanks for your help!

rovingcowboy · Post by **rovingcowboy** » Sun Sep 18, 2005 10:36 am

you are always going to run in to trouble with converting from one compression to another. it is best to make them in to wav files and then put them back in to the other compression.

why use mp3? at a lower bit rate?

mp3's at 256 are large and sound good but ogg at 196 sound the same as the 256 mp3 and are smaller then the mp3.

still mp3 is what you want then i would not go any lower then 196 for them.
i have had some songs where the background singers are saying words soft behind the main lyrics and the background singers all of a sudden sound like they are saying something else when i used small then 196 bitrate on the mp3's

so there are some songs that need the higher bit rate.

Lutz · Post by **Lutz** » Mon Sep 19, 2005 4:40 am

Cowboy, thanks for your reply. I was hoping to avoid the time consuming step of going to wav first, especially as I thought that MM already does this internally during transcoding. Nevertheless, I will give it a try.

Please let me know if there is any other idea, how to generate reliable transcoding results with MM. I really like managing my files with MM, but the recent experience makes me wonder if I am just not enough of an audio expert or if there is an easier solution than MM.

Thanks!

rovingcowboy · Post by **rovingcowboy** » Mon Sep 19, 2005 8:32 am

the thing i am looking at that might be the cause is that you are useing the ABR and not CBR or the VBR. i think trying to keep a song at the one bitrate is not really the best thing to do.

i use vbr or cbr. i make media monkey use the highest and lowest settings for bit rate that i pick not the slider on the left.

and it seems to work better as i don't get the errors when i do need to convert to mp3 or wma for my sisters portable player.

that is the reason i say to go to wav first. you have them in abr.

wav will take it back to what it should be 1411 br. and that will give enough for the program to chose from when making them back in to mp3.

now there might be some loss of quailty but not much and you have a better chance of keep it by going back to wav first..

plus if there was anything wrong like a skip in the song then you can listen to it in wav form and see if the skip was caused by the compression being to low. i have found some skips like that. so i raised the bitrate and got rid of the skip or snap noise.

plus i have said in so many posts that the compression on some songs removes words or sylabols from the song making the lyrics sound strange.

as in the song called IN The Navy by the villiage people. when compressed in too low a bit rate, the song lyrics change from "what am i gonna do in submarine." to "what the fu,, am i in a submarrine."

the reason is the background singers are sing word that are over lapped by the main lyric and too low a rate will cut out the lower volume words and it realy makes a differance as you can see.

that is what happens with that song going to 128br on mp3's it needs no less then 196 br. but there are lots of others out there that need a little larger bit rate, those are the ones where people speak the lyrics and back ground singers sing low background lyrics or the singer whispers and the back ground is louder then the singer.

so keep that in mind when you make them in to smaller bitrates.

i also have had trouble with no 2 second silent space on the front and end of the song. my defragmentor has caused some songs where i cut the silent space off. to be come damaged and have snapping sounds on both ends of the song.

that is caused by the defragmentor opening and closing the file it is the only reason i can figure out.

as i adjusted the songs to get rid of the snapping noise when in wav then added the 2 seconds of silent space on both ends of the song and compressed them again.

i have not had any damaged files from the defragmentor again.
so the defragmentor must have been opeing the door and ripping the door handle off the file and then slamming it shut and smashing the files toes in the door.

i know that sounds like it would not do it? but theres is no other files that were damaged only the ones i had with out silent space.

Lutz · Post by **Lutz** » Thu Sep 22, 2005 3:44 am

OK, so the WAV workaround seems to work pretty reliably. I am wondering if I really have to do this manuall. I was assuming that MM already does some kind of internal WAV conversion when transcoding. After all, isn't software meant to automate manual tasks?

However, I am gonna stay with the WAV trick untill all of my 60 GB of OGGs are properly converted into MP3s.

Regarding the bit rate question: I chose the preset "Studio: ABR ~256 kbps", just because it sounds like it provides good audio quality. Now, after reading the MM online help once more, I understand that the preset "Extreme,
VBR ~256 kbps" seems to be preferrable. So I will chamge to this one instead.

Again, thanks for your help.

rovingcowboy · Post by **rovingcowboy** » Thu Sep 22, 2005 9:09 am

I think media monkey does do the internal wav conversion when transcoding. but i believe the abr is messing up with media monkey.

not sure but i have no trouble with the reconverting to mp3 or wma from my ogg files and i use the vbr format.

there is one other thing. if your trying to use the same folder the ogg file is in when you convert them to mp3's then media monkey will not overwrite the ogg and will crash or cause trouble.

it is best to use a different folder.