Log in

View Full Version : Batch MP4 tagging that doesn't write excess data


qyot27
12th January 2008, 03:38
The thread title is pretty self-explanatory, but I'm looking for something that can help me tag multiple MP4 files (for instance, with the same Artist/Album/Genre/Year info) but doesn't spit out a file that has data in it I don't want.

My typical routine in this is, after encoding the files themselves, I demux them to AAC with dBpoweramp Music Converter (using the AAC to MP4/MP4 to AAC plugin), and then subsequently remux them using the same plugin. This helps trim down the filesize to the bare minimum. I then manually add the tags to each file using Audiocoding's in_mp4 plugin for Winamp. The resulting file is usually the same size as the original trimmed-down file.

Problem is, this is pretty cumbersome and lengthy. So I'm looking for a program that can do this in batch. Testing iTunes, which can do batch tagging like I want, it consistently adds about 2 KB to the filesize, without fail. This is a chart I made illustrating it (even if I didn't have to):

http://img213.imageshack.us/img213/4489/tagsizesun9.png

Maybe the reason is the padding issue I read about that the AtomicParsley website mentions concerning iTunes' tagging. I don't know.


Are there any solutions that can do what I'm looking for that match the output from the Audiocoding method rather than adding unnecessary size to the file like iTunes does? Searching on Google for 'mp4 batch tagging' and whatnot seemed to just want to bring up sites looking to peddle the typical 'media conversion software' ripoffs and spam sites.

Schrade
12th January 2008, 21:22
I believe the development builds of MP3Tag (http://www.mp3tag.de/en/) might do what you want. I don't think it'll strip out all the extraneous stuff though :-/ but I haven't tested for that.

http://developer.mp3tag.de/

I sort of stumbled across its MP4 support by retagging video files.

qyot27
13th January 2008, 13:28
It looks like it's actually exactly what I needed, thank you. While at first it seems to inflate the filesize (on the case of Perfect, it did so by 4 KB, twice as much as iTunes), I found that using the 'Optimize MP4' function shrinks the size back down to what I expect it to be.

I'm also happy to find the option in its config to preserve file modification times when writing tags - that helps immensely. My only two complaints, and they're minor ones, is that it doesn't have a place for the Totaltracks field and that it seems if I want to edit many files with slightly differing info (only the Title field, for instance), then I have to save after each edit rather than at the end. But I can live with that.