How TagJet handles tags

As was previously mentioned TagJet supports ID3v1 tag and all versions of ID3v2 tag: v2.2, v2.3 and v2.4. You do not need to worry which version of ID3v2 is in a file, TagJet will read any of them. But a tag is stored only as version 2.3. Because it is the most common version and is supported by most programs that can read the tags. Version 2.2 is already obsolete, and version 2.4 is supported by far from all programs now.

New field values are not written directly to files during tag editing. Tags are saved to files only after you click Save or SaveAll, before this action files remain unchanged. If you just close the program without pressing these buttons, then files will not be changed, and the results of your editing will be lost.

If at least one field of ID3v1 or ID3v2 tag was changed, then * (asterisk) is put near the file number to show that the files data can be saved.

Before you saved the tags, any tag change can be canceled by clicking Undo button or reverted by clicking Redo button.

In the process of saving a file TagJet usually decides itself when to create, delete or overwrite the tag in the file, on the ground of tag fields’ content after editing. For you these actions are completely transparent and you should not worry about it. However, below are details of how exactly TagJet saves tags. To let you understand the refinements of the programs work.

ID3v1 tag is located at the end of the file. If after editing all the tags fields are empty then the tag is not saved in the file and if before editing the tag was present in the file then it is removed. If after editing the tag is not empty, i.e. at least one of its fields is filled, then it is saved in a file. If initially it was absent then it is created.

ID3v2 is located at the beginning of the file. If initially the tag was absent and in the editing process some of its fields were filled then it is saved in the file, but this file have to be completely rewritten to make room for the tag.

If initially the tag was present in the file but increased in size, and space allocated for it is not enough then it is also necessary to rewrite the entire file.

In cases when there is a need to rewrite the entire file, TagJet reserves 1KB of additional space to reduce the possibility of rewriting the entire file in the future.

If initially the tag was not empty and in the editing process you have cleared all of its fields then the tag is deleted. But the place allocated to the tag is saved to avoid rewriting the entire file now and during the next tag saving.

If an ID3v2 tag must be completely removed then a tag of the minimum size remains in the file to indicate the place allocated for it. Otherwise TagJet and other programs will not be able to recognize that the place is allocated for the tag when the next time MP3 file is opened.

Total file overwrite during ID3v2 tag saving is relatively slow operation. This is noticeable if you save a lot of files at once or the files are very large. If you want to avoid this definitely you should use ID3v1 tag because it is always very fast to work with it.

TagJet does not display absolutely all fields contained in an ID3v2 tag. All invisible fields or fields generated by other programs are retained without change.

Even if in TagJet you cleared all fields of a tag (either manually or by selecting "Delete Tag"), but there are invisible fields in the tag then the tag is not deleted and these fields are saved.