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tv69
2010-11-02, 15:51
Hello,

I am wondering what the Rescan function 'Look for new and changed music' actually does?

If I change tags on various tracks in my library, will the changes be picked up by using the 'Look for new and changed music'?

I already tried a test of re-tagging the genre on about 1000 songs. There were previously only about 9 songs tagged with that genre. After a rescan, it appears that the tags were not picked up and I still only have 9 songs in that genre when I should have over 1000.

'Look for new and changed music' is much quicker that a full 'clear library and rescan', so it would be a shame if tag changes do not get picked up by using the 'Look for new and changed music' rescan method.

Are others finding similar difficulties?

Thanks,

TV

ChrisNY
2010-11-02, 16:41
My guess is that the program you are using for tagging may not be updating the file last modified attribute which is what I am assuming SC is looking at. Many times you don't want the last modified to be changed, particularly if you don't want to have all of your re-tagged files to show up in the "New Music" section of SC (which is why I don't update the date when I update tags). A full rescan should get you back in business and if you don't mind the New Music issue you could look into updating the file modification settings in your tagging software of choice.

tv69
2010-11-02, 18:43
My guess is that the program you are using for tagging may not be updating the file last modified attribute which is what I am assuming SC is looking at. Many times you don't want the last modified to be changed, particularly if you don't want to have all of your re-tagged files to show up in the "New Music" section of SC (which is why I don't update the date when I update tags). A full rescan should get you back in business and if you don't mind the New Music issue you could look into updating the file modification settings in your tagging software of choice.

Chris,

Thanks for the input. You are right, the tagging prog I use is set up not to change dates when tags are changed. I really would prefer to keep it that way so I guess a full purge and rescan is the only way to get changes read into the SB server.

Thanks again,

TV

JJZolx
2010-11-02, 18:54
If I change tags on various tracks in my library, will the changes be picked up by using the 'Look for new and changed music'?


They should be if either the last modified timestamp or the file size changes.

Usually, the file size will not change, since most types of tag have extra padding space in the tag. Most tagging programs will take advantage of the padding and can expand existing fields or add new ones into the padding, avoiding the need to rewrite the whole file. Deleting tag fields just adds to the padding.

Some tagging programs can also preserve the file modification date. This is helpful for keeping the 'New Music' page in Squeezebox Server in the correct order, but it can also prevent a new & changed scan from detecting that a file has changed.


I already tried a test of re-tagging the genre on about 1000 songs. There were previously only about 9 songs tagged with that genre. After a rescan, it appears that the tags were not picked up and I still only have 9 songs in that genre when I should have over 1000.

'Look for new and changed music' is much quicker that a full 'clear library and rescan', so it would be a shame if tag changes do not get picked up by using the 'Look for new and changed music' rescan method.

Are others finding similar difficulties?

What you'll find more than anything is that old data remains after you've removed it from the tagging of the library. For instance, if you were to correct the misspelling of an artist's name and then run a new & change rescan, the new spelling will be picked up, but you will often still see the old artist in the library.

JJZolx
2010-11-02, 18:58
You are right, the tagging prog I use is set up not to change dates when tags are changed. I really would prefer to keep it that way so I guess a full purge and rescan is the only way to get changes read into the SB server.

Not necessarily. I wrote a little VB script for myself that bumps the file times by one second so that a new & changed scan will pick up the changes. There are also many Windows Explorer extensions for altering file properties that can be used similarly to alter the date modified. By just bumping the file dates by seconds you can keep their original order in New Music, but still allow a new & changed scan to see that they've changed.

tv69
2010-11-02, 19:08
Thanks JJZolx,

Did not consider that, probably because I am not a programmer. :^)

I could definitely live with that method for quick rescans of re-tagged files and every so often do a purge and scan to get rid of any leftover 'old' data.

Could there be a tagging software that employs this type of feature, bumping the time by just 1 second?

TV

juzi
2010-11-03, 07:24
well, in Linux I use 'easytag' which is quite good and has an option to update the modification time of the files as well. But you are probably a Windows user. AFAIK, mp3tag should also update the file date, doesn't it?

Cheers
juzi

aubuti
2010-11-03, 07:44
AFAIK, mp3tag should also update the file date, doesn't it?
It's an option on mp3tag , so the user can set it the way he/she chooses. I don't remember what the default is, but it's an easy setting to find. I have mine set to update the timestamp after editing tags.

tv69
2010-11-03, 15:37
Hi,

I was not too clear in my previous post. I use Tag&Rename and there is the option to have the file date changed when altering tags or you can have the date stay the same.

I was curious to know if there is a tagging software that alters the file time stamp by just 1 second just like JJZolx's VB script does?

Thanks,

TV

paulster
2010-11-03, 23:33
I wrote a little VB script for myself that bumps the file times by one second so that a new & changed scan will pick up the changes.
Care to share, so I don't have to write one from scratch?! That's a great solution as it should keep everything in the correct order.