Just like Vorbis comment it defines some standard fields, but it also defines some formats for those fields (like what a date should look like).
(ii) What's the point in storing binary data in a tag? I don't think storing images in files is a good idea (and Klemm seems to agree that 'long' tags is not a good idea).(x) I store images and other goodies in the tags. There's no reason to be afraid of 30kb of extra data with a modern computer...images should never be added to an audio file.if the data is important for the audio-visual representation, an additional container format should be used to store data and relations between the data. A well designed example is the MPEG-4 system stream. Tags should be tags and not the worst possible concept of a container format.
It is strongly recommended that the data size be stored in the tags. The size should normally be in the roughly one kilobyte, never more than 8 kilobytes.
The foobar2000 player can also tag MP3 files with APEv2 tags instead of ID3 tags, because they are considerably easier to write and more flexible.However, because ID3 was designed with the MP3 format in mind and APEv2 was not, there are some complications. For example, the string APETAGEX signals the start of an APEv2 tag, but the string TAG signals the start of an ID3v1 tag. If the TAG in APETAGEX ends up where an ID3v1 tag is expected, it may be read incorrectly. ID3 also has an “unsynchronization scheme” to ensure players do not try to play the tag data as audio; APEv2 has no such scheme, and APEv2 tags may result in errors or static at the end of files.
I've seen about 5 links from your post but not APE key!! Thanks! That's great for the start, from now I can be aware how close are my tags to the recommended tags - and then reasonably guess compatibility with software supporting APE in MP3. If we can define tags as we want, why we don't name them in Czech and Brazil Portuguese? I suppose everyone wants to be at least basically compatible, and when I do that, I want to do that properly. Unfortunately there aren't keys for Album Artist or Encoder but at least I see some logic... spaces in label names are okay.
(side note to your previous Topic, Rodrigo: even APE doesn't expect multiple strings in Title, what a mess :-)))
Q2: ok binary flag is fine. Just don't understand the statements @ FAQ & format description. First I was thinking that it was about APEv1 and not v2 but then I found that it was from the time when v2 was out. Fear of long tags might be related to problems with streaming and lenght of gap between tracks. It can happen that APE is not designed for large/binary tags even if it allows them and ID3v2 handles them better. One of the formats may have lesser gaps between the tracks and less problems with streaming. Yet thanks for results of your test run.
Q3: ID3v1 is compatibility saviour. I play my music on parties, use it in car stereo, my mobile phone or MP3 player borrowed from my sister and I am planning to purchase multimedia centre to a living room.. probably none of these devices knows APE. I will need both APEv2 and ID3v1 to cooperate. First part of question was technical, I'm not educated in this matter, I was just curious if APE tags reside in MP3 "legally" and basically the same as ID3 (just different type of tags/metadata), or, because they were originally designed for APE files, are in MP3 by some kind of hack which perfectly works but uses grey points in specification, goes beyond recommended values etc. I am interested because of stability - e.g. may a player, which is very old and reads only ID3v1 tags but MP3 handling has properly implemented (no bugs), have problems with skipping APE tag, or can't it wrongly consider as a part of audio stream?
I'd be happy to finish the implementation of album art APEv2 in Winamp if someone can provide reliable test files.
I already have my way of naming tags, but if we go further in this and want to make a new one, that maybe can serve for others, I'm in. At present I don't use spaces, but underlines in my custom tags (album_artist, date_of_reference, recording_info and VBR_mode).
Quote from: Tigermess on 29 December, 2011, 05:42:41 PM(side note to your previous Topic, Rodrigo: even APE doesn't expect multiple strings in Title, what a mess :-)))What do you mean? It is working for me in foobar.
I may go with you in this and start saving id3v1 too. Since id3v1 should be in start and apev2 in end of file, shouldn't be a problem. Tests needed though.
1.3 years later the embedding was done, without explaning how come that for years the rule was held and now it was breached. A demand for embedded pictures had certainly its role; if the rule itself was proven wrong, surpassed by technological improvement or simply ignored is hard to tell.
Quote from: benski on 29 December, 2011, 08:49:15 PMI'd be happy to finish the implementation of album art APEv2 in Winamp if someone can provide reliable test files.Great news. What about these samples? I admit there are not many mp3s... Alex B could create them.
Quote from: rodrigomartinho on 30 December, 2011, 12:32:44 AMI already have my way of naming tags, but if we go further in this and want to make a new one, that maybe can serve for others, I'm in. At present I don't use spaces, but underlines in my custom tags (album_artist, date_of_reference, recording_info and VBR_mode).Non-binding standards would be nice. We all solve similar problems as software developers do too. Maybe I'll try to push that later. With all respect to your naming scheme - from what I've seen now on very limited range of software (fb2k, Mp3tag, Winamp), two prefer spaces between words, one puts the words together - if you still can change it, I'd rather stick with one of those schemes. If you have any reasons to keep it - habits, friends - no problem :-)
Quote from: rodrigomartinho on 30 December, 2011, 12:32:44 AMQuote from: Tigermess on 29 December, 2011, 05:42:41 PM(side note to your previous Topic, Rodrigo: even APE doesn't expect multiple strings in Title, what a mess :-)))What do you mean? It is working for me in foobar.It's not a big deal. In the table, column "Recommended format of value" - Artist, composer, comment and others have one of the recommended values "List of UTF-8 strings" i.e. multiple strings. Title has only single string recommended. It was not against you, I was just surprised that multiple titles are missing in recommendation. It's the same behaviour which foobar2000 has now with ID3v2.4 - no multivalues allowed in a title.Btw how do you plan to tag single-file rips of albums? Will you write all song names to the title? And all track numbers as multivalue too?
Quote from: rodrigomartinho on 30 December, 2011, 12:32:44 AMI may go with you in this and start saving id3v1 too. Since id3v1 should be in start and apev2 in end of file, shouldn't be a problem. Tests needed though.In fact you won't even notice it, APE tag will always have priority and ID3v1 is saved in the background. The tags are imperfect but at least will be some... it will serve you well. Just beware, ID3v1 is in the end of file too, its written right after APEv2 tag - that's the reason for warning about possible confusion between TAG as a starting string for ID3v1 tag and APETAGEX as delimiter for APEv2. I hope if there were real problems, we already knew that, however ID3v2 is definitely safer - as ID3v2 is the one positioned in the beginning of the file.
It just came to me now that after I properly mapped the discnumber tag in apev2 to just "disc", my previous setup of saving both apev2 and id3v2.4 should work between foobar and mp3tag. I'll test it again. And maybe it will work with other combinations, such as apev2 + id3v2.4 + id3v1, or apev2 + id3v2.3 + id3v1. I'll test that too and, if works indeed, it would be possible to have a scheme where complete tags work in foobar (apev2) and incomplete but largely supported tags would work in software that doesn't handle apev2. This would be the best of both worlds and seems this is our goal.
APETAGEXÐ...Å.......... ................COMPOSER.Pixinguinhap.......MUSICIANCREDITS.Pixinguinha:.Donga:.(...)PUBLISHER.Sinter SLP-1038........BAND.A Velha Guarda........DISC.1/1APETAGEXÐ...Å..........€........TAGQue Perigo....................A Velha Guarda................A Velha Guarda................1955..............................ÿ
I am fairly sure that APEv2 and ID3v2 are mutually exclusive, i.e. disruptive of each other. Hence foobar2000 and other applications offering them on their own or with ID3v1, but not in combination. This may explain some of your observations.
I didn’t say that they can’t be added; I said that perhaps they shouldn’t! And, if such is the case, that may explain your findings.This is based upon the fact that foobar2000 doesn’t allow the user to write both types of tag to one file, and my presumption that there’s a good reason for this choice.
This doesn't happen if you have id3 and ape tags in the same file. In the same example as above, when you save MIXARTIST in mp3tag, it will save TPE4 in id3 and MIXARTIST in ape. When foobar reads this file, it reads both tags and shows all frames, despite which tag type it is from, in the properties window. So it will show REMIXED BY (the TPE4 frame read from id3) and MIXARTIST (read from ape and shown unchanged). If you save this tags in foobar, it will create the TXXX MIXARTIST in id3 (since this isn't the name it expects for TPE4) and the REMIXED BY in ape. It was this kind of duplication (principally noted in DISCNUMBER) that was bothering me. Now that I finally understood it, I can see that, apart the unnecessary replication of frames, there isn't much to worry about this. And, since mp3tag has a mapping function, but foobar doesn't, it is possible to have full compatibility between frame names if one uses exclusively the foobar names, mapping them in mp3tag. This will be my next test.
I began to compare tag "standards" and their implementation in popular software; for this purpose I did a table.
I speak a little bit portuguese, no need to translate :-) Your table is very comprehensive!! And very good in its ID3v2 part. Mine tries to focus on comparison. Well, nice share... it's complete list of fields which fb2k and mp3tag recoginze, I will have a use for that.
Today I noticed that Soulsearchingsun updated Foobar2000:ID3 Tag Mapping, thanks for the good job :-)In last two weeks I updated table with Winamp, few rare MusicBrainz recommendations, added more fields and made my pick fields I am going to use (it's about thirty ). ATM I have about 300 various files to tag (cd rips, netlabels music, sets, live and radio shows...), I want to test it and then I will put it out.Rodrigo, I found out there's no problem editing ALBUM ARTIST both in Foobar and Mp3tag when I made proper mapping in Mp3tag - even without underscore between the words I suppose you already know.. you gave me the notice about possibility of field remapping in Mp3tag and its perfectly achieveable just with that.