split or merge mp3 files based on playing time ?

lin · Post by **lin** » 2005 Oct 20, 12:31

I have audiobooks wich are often split into many small files ,so sometimes you get as many as 1000 tracks ,lasting a minute or so.
I use mp3bookresizer which allows me to split or merge the tracks based on time ,so i make the tracks 1 hour long(for convenience on my mp3 player),
Alas ,the limit on this program is a 1000 tracks.
Would it be possible to have a "duration"option in the split/merge option?
Since the bitrates vary between books, filesize is no indication in relation to playing time.

Thanks ,Lin

Post by **nikos** » 2005 Oct 20, 13:11

i can't help you here either!
mp3 file splitting/merging isn't just about putting a few segments one after the other, you'd have to think of headers etc (e.g. to keep each split segment playable)

the splitter in x2 is meant for transferring or emailing a file that's too big to fit in one slot

lin · Post by **lin** » 2005 Oct 20, 14:16

i think you underestimate the capabilities of your program ! if i merge 2 mp3 files ,not a split second is lost where the 2 files are merged, even the tag is still there !
cheers,Lin

Post by **nikos** » 2005 Oct 20, 15:57

that's true but when split you'll only be able to play the first chunk, if anything at all. Likewise if you attempt to merge a few small mp3 files with x2 then you'll only be able to hear the first one plus rubbish!

some header/tag management is required for what you are after

lin · Post by **lin** » 2005 Oct 20, 17:57

nikos wrote:that's true but when split you'll only be able to play the first chunk, if anything at all. Likewise if you attempt to merge a few small mp3 files with x2 then you'll only be able to hear the first one plus rubbish!

some header/tag management is required for what you are after

I have to disagree , i am doing it all the time ,splitting, merging mp3 files ,and listening to them afterwards ,pefect quality!
try it out for yourself ;take two tracks ,(from an audiobook? )listen to the end of the first track ,and listen to the start of the next track, note the time ,then merge them ,go to the time where the first track ended (i use "1 by 1 player it has a counter) and listen.
Then , split them again , and listen, you'll hear no difference!

Lin

Starsurfer · Post by **Starsurfer** » 2005 Oct 20, 18:46

that includes zips, rars, exe..& the like..... right ?

lin · Post by **lin** » 2005 Oct 20, 19:40

Starsurfer wrote:that includes zips, rars, exe..& the like..... right ?

Huh...

is this remark meant sarcastical ?

snakebyte · Post by **snakebyte** » 2005 Oct 21, 01:14

lin wrote: I have to disagree , i am doing it all the time ,splitting, merging mp3 files ,and listening to them afterwards ,pefect quality!
try it out for yourself ;take two tracks ,(from an audiobook? )listen to the end of the first track ,and listen to the start of the next track, note the time ,then merge them ,go to the time where the first track ended (i use "1 by 1 player it has a counter) and listen.
Then , split them again , and listen, you'll hear no difference!
Lin

How are you splitting your Mp3s? If you are using some external tool then it may already be handling Mp3 headers for you. Try split file and merge file functionality of xplorer2. It won't work with your Mp3s as these files need special header handling in order to keep Mp3 playable after split or merge.

narayan · Post by **narayan** » 2005 Oct 21, 04:39

I haven't tried splitting an MP3 file with x2, but merging two different files (which were made with mp3grabber separately) worked just fine.

Going by your information, the second file's header would land in the middle of the resultant file; but this apparently causes no harm: the result is a seamless mp3.

The combined file does not have any glitch/pop/scratching sound/noise/etc.

I checked the soundwave with Audacity also--No problems!

lin · Post by **lin** » 2005 Oct 21, 07:44

snakebyte wrote:
lin wrote: I have to disagree , i am doing it all the time ,splitting, merging mp3 files ,and listening to them afterwards ,pefect quality!
try it out for yourself ;take two tracks ,(from an audiobook? )listen to the end of the first track ,and listen to the start of the next track, note the time ,then merge them ,go to the time where the first track ended (i use "1 by 1 player it has a counter) and listen.
Then , split them again , and listen, you'll hear no difference!
Lin
How are you splitting your Mp3s? If you are using some external tool then it may already be handling Mp3 headers for you. Try split file and merge file functionality of xplorer2. It won't work with your Mp3s as these files need special header handling in order to keep Mp3 playable after split or merge.

As i said before i can split and merge mp3 files with explorer2 with no loss of quality , without using some external tool .
I don't know ,or want to know about special header handling issues, no need to.

Just go and do it , split and merge an mp3 in eplorer2 and you'll see it works ;
only takes a minute !

Lin

Post by **nikos** » 2005 Oct 21, 10:53

you're right!
i guess we don't understand mp3 binary format at all

i checked the file contents and it appears that the first chunk has an ID3 block to begin with but no other identification. Probably this ID3 isn't required at all

that is extraordinary though and the exception to the rule!

Starsurfer · Post by **Starsurfer** » 2005 Oct 21, 12:46

lin wrote..

Huh... Confused is this remark meant sarcastical ?

i posted it in context with nikos' post & it didn't appear just after his post like i expected- was just confirming the filetypes that one could split/merge safely

nijos wrote..

the splitter in x2 is meant for transferring or emailing a file that's too big to fit in one slot

-

lin · Post by **lin** » 2005 Oct 21, 16:06

Starsurfer wrote:lin wrote..
Huh... Confused is this remark meant sarcastical ?
i posted it in context with nikos' post & it didn't appear just after his post like i expected- was just confirming the filetypes that one could split/merge safely

nijos wrote..
the splitter in x2 is meant for transferring or emailing a file that's too big to fit in one slot
-

Ok , fine , no offense taken

Lin

lin · Post by **lin** » 2005 Oct 21, 16:17

nikos wrote:
you're right!
i guess we don't understand mp3 binary format at all

i checked the file contents and it appears that the first chunk has an ID3 block to begin with but no other identification. Probably this ID3 isn't required at all

that is extraordinary though and the exception to the rule!

Right , i'll come back to my original question:
"Would it be possible to have a "duration"option in the split/merge option? "
I have no idea what this would mean ,technically ,and how many people would use this option.
The commercial mp3 splitters and mergers i tried are just bloatware or buggy.
thanks Lin

Post by **nikos** » 2005 Oct 21, 16:28

as i said (and demonstrated in this thread

) i know nothing about mp3 so i couldn't know anything about durations

what you need calls for a specialized tool, perhaps command line only without gui. It doesn't have anything to do with a generic file manager like x2

ps if you check the duration of the full MP3 (e.g. in winamp) then it's easy to figure out how big each chunk should be to reach a target split time:

split_size = total_size * (piece_duration/total_duration)

some manual calculations are required