Documentation of %_video_{bitrate, width, height}% info fields

It seems that some information fields, which can be used much like (read-only) tag fields, are not documented on the English and German websites, anything relating to videos in particular: %_video_bitrate%, %_video_width%, %_video_height%.

I wonder whether that is intentional, because they only work for certain codecs (H.264 at least), but not for others (e.g. AV1, VP8 and VP9) which may be encountered in the wild (e.g. in YouTube rips). Since WebM support has been added in v3.01, this becomes more relevant because this format (which is a subset of Matroska / MKV) requires a Google VP video codec.

If you look closely at the name then you will notice that it starts with an underscore.
This indicates that it is a field just for your information. Usually, such fields cannot be modified by MP3tag (or the users of MP3tag) and are read-only.
You see a lot of information fields if you use the button with the right arrow to open the underlying menu and open the submenu for information fields.
When you scan through the list then you will notice that hardly any of the fields is actually described somewhere.
So in a way, I don't see a bug here.

Only checking English documentation for Columns, Converter and Export, (at least) the following fields seem to be documented nowhere:

  • %_video_height%, %_video_width%, %_video_bitrate%
  • %_subsong%, %_subsong_count%

Some fields are only documented in one place (usuallybecause they only apply there, but I'm not sure for %_cover_{width, height}%). Perhaps they should be documented in a central place and indicate there, in which places they apply.

Collected Documentation

Technical info

Placeholder Description
%_bitrate% Bitrate in kbit/s
%_codec% Codec
%_cover_mimetype% Mimetype of first cover art in the tag of the file
%_cover_size% Size of first cover art in the tag of the file in bytes
%_cover_type% Cover type of first cover art in the tag of the file
%_cover_height% Cover height of first cover art in the tag of the file in pixels
%_cover_width% Cover width of first cover art in the tag of the file in pixels
%_covers% Count of cover art in the tag of the file
%_id3v2_character_encoding% Encoding of the ID3v2 text frames of the file.
%_length% Length (formatted)
%_length_seconds% Length (in seconds)
%_mode% Mode
%_samplerate% Sample rate
%_tag% Available tag types in file
%_tag_read% Displayed tag type
%_tag_size% Size of all tags in bytes
%_tag_size_appended% Size of all appended tags in bytes
%_tag_size_prepended% Size of all prepended tags in bytes
%_tool% Additional codec information (not available for all supported audio formats).
%_vbr% Bitrate type or compression profile

File name / path info

Placeholder Description
%_directory% Name of the parent directory
%_extension% File extension
%_filename% File name without extension
%_filename_ext% File name with extension
%_folderpath% Path without file name
%_folderpath_rel% Folderpath relative to Export output file if output and track files are on same drive, else absolute
%_path% File name with path
%_parent_directory% Name of the grandparent folder
%_volume% Volume label
%_workingdir% Name of current working directory
%_workingpath% Path of current working directory
%_playlist_filename% File name of current playlist without extension
%_playlist_filename_ext% File name of current playlist with extension
%_playlist_folderpath% Folderpath of current playlist

File properties

Placeholder Description
%_file_create_date% Short creation date
%_file_create_datetime% Long creation date
%_file_create_datetime_raw% Long creation date (unformatted)
%_file_mod_date% Short modification date
%_file_mod_datetime% Long modification date
%_file_mod_datetime_raw% Long modification date (unformatted)
%_file_size% File size in human readable format
%_file_size_bytes% File size in bytes
%_file_size_kb% File size in kilobytes
%_file_size_mb% File size in megabytes
%_crc% CRC32 value of file content
%_md5% MD5-Hash of the file (slow!)
%_md5audio% MD5-Hash of the audio part of the file (slow and only supported for ID3- and/or APE-only tagged files)

System

Placeholder Description
%_app% Mp3tag, e.g. Mp3tag v3.01
%_counter% Current counter value (ascending from 1) of the immediately containing loop
%_date% Short date
%_datetime% Long date
%_max_counter% Maximum value of counter of the last closed loop.

Global placeholders

(providing totals for the preceding $loop/$loopend)

Placeholder Description
%_total_files% Total number of files
%_total_size% Total file size (formatted output)
%_total_size_raw% Total file size in bytes
%_total_time% Total playing time (formatted output)
%_total_time2% Total playing time (formatted output without days)
%_total_time_raw% Total playing time in seconds

PS: Several of the lists of fields are so long they require scrolling on my screen. Therefore it may make sense to group them differently, e.g. not a single expanding sub-menu for all info fields but for audio, video or technical info fields, file system info fields and other info fields.