KataLib
KataLib are many programs in one Application:
Librarian
- Organize and search all your music/audio files
- Create Collections of tracks from files, YouTube links/playlists
- Download Cover images from the internet or apply your own
- Use custom tags for files or Collections to make searching easier
YouTube downloader
- Download any YouTube link or playlists
- Use any resolution or stream quality
- Automatically collect YouTube links that you copy in your browser
Player
- Play any audio file or YouTube link
- DJ mode with auto or manual crossfades between tracks
- Play the YouTube links in a uniform level
- Load and save WinAmp playlists
Converter
- Convert between many different audio formats
- Auto Level/Trim output
- Convert YouTube video links to any type of audio files
MetaData editor
- View and edit metadata information (IDv2 tags)
- Download missing info from the MusicBrainz db and also lyrics
- Change the metadata in many files in one go (Batch mode)
- Full or Compact View
- Easy to use drag & drop interface
- and more...
Input Formats:
- ".mp3" - MPEG Audio Stream, Layer III (lossy)
- ".aac" - Advanced Audio Coding (lossy)
- ".m4a" - MPEG-4 Part 14 (audio only) can contain AAC (lossy) or ALAC (lossless) stream
- ".ape" - Monkey's Audio (lossless)
- ".ogg" - Ogg/Vorbis (lossy)
- ".oga" - Ogg/Opus Audio (lossy)
- ".opus" - Opus Interactive Audio Codec (lossy)
- ".flac" - Free Lossless Audio Codec (lossless)
- ".ac3" - Dolby AC-3 (lossy)
- ".wma" - Windows Media Audio (lossy)
- ".wav" - Waveform Audio (lossless)
- ".aif" - Audio Interchange File Format (lossless)
- ".mp4" - MPEG-4 Part 14 multimedia (extracts the aac audio stream)
- ".mkv" - Matroska Multimedia Container (extracts the audio stream)
- ".avi" - Audio Video Interleaved Container (extracts the audio stream)
- ".mov" - QuickTime File Format (extracts the aac audio stream)
- ".flv" - Flash video (extracts the aac audio stream)
- ".wv" - WavPack (lossless)
- ".mpc" - Musepack AKA MPEGplus (lossy)
- ".mp2" - MPEG-1 Audio Layer II (audio only) (lossy)
- ".mpga" - MPEG-1 Audio Layer III (audio only) (lossy)
- ".mpeg" - MPEG-1/2 (extracts the MPEG-1 Audio Layer II audio stream) (lossy)
- ".webm" - WebM - can contain Ogg or Opus audio stream (lossy)
- ".dts" - DTS - Digital Theater Systems
- ".m4b" - MPEG-4 Part 14 (audio only) (lossy) used for audio books
- ".dfs" - Direct Stream Digital file (lossless) (convert-only)
Output Formats:
- ".mp3" - MPEG Audio Stream, Layer III (lossy)
- ".m4a" - MPEG-4 Part 14 (audio only) containing AAC (lossy) stream
- ".aac" - Advanced Audio Coding AAC (lossy)
- ".ogg" - Ogg/Vorbis (lossy)
- ".opus" - Opus Interactive Audio Codec (lossy)
- ".flac" - Free Lossless Audio Codec (lossless)
- ".wav" - Waveform Audio (lossless)
Full online user guide here
Download the latest version
Get KataLib 5.1.0.0 setup.exe, use it and if you like it, consider to
For older releases, see here..
...also, Compatibility-wise...
Windows XP
From version 4.x.x onwards, KataLib dropped support for Windows XP.
The last XP compatible build can be found here.
To use it, you also need an XP compatible FFmpeg.exe in "Preferences".
Some XP compatible builds can be found here.
Windows 7
KataLib can't start if Microsoft Visual C++ 14.0 is not installed.
Get it here.
The Windows 7 32bit version also needs the KB2533623 update thats is included in
KB3063858
(direct link).
Version History:
- 5.1.0.0
Added:- Different audio outputs for the main player and headphones (or any other audio device) can now be selected in Preferences.
- Preview/Cue dialog that let us audition any track of the playlist without
interupting the current playback.
Useful for DJs, to audition tracks while they are mixing.
- Updated yt-dlp library to version 2025-10-22.
- Custom sorting of the PlayList (manual re-arrangement of the tracks) is now always saved, and it's an option we can choose in the PlayList sorting menu.
- Downloading and automatically resizing an album cover was failing.
- 5.0.0.0
Added:- Visualization Video Setup dialog with real time preview of how the rendered video will look like.
- Right clicking the Stop button stops with fade out, right clicking the Play button starts a crosfade with the next track.
- Option to remove all / missing tracks from the Recent tracks menu of the playlist.
- Dropped support for Windows 7/8 and 32bit systems, because of mandatory update of Python to version 3.10.x. (yt-dlp stopped supporting erlier Python versions.)
- Updated yt-dlp library to version 2025-10-22.
- Spotify playlist support is back (using YouTube tracks of course)..
- Hot key actions can be disabled one at th time by selecting the "None" option.
- Some m3u playlist files could not be parsed correctly.
- 4.5.5.0
Added:- New Peak Meter visualization.
- Option to create a visulization video using the current track's audio.
- When dropping a playlist file on the Playlist while the ctrl modifier is held, the dropped playlist's tracks will be appended to the existent tracks.
- YouTube tracks that were found in the "Find Tracks" dialog can directly dropped to the playlist with the mouse.
- YouTube playlist could not load more than 100 tracks.
- Sometimes, double clicking between tracks, blocked the visualization display.
- 4.5.3.0
Added:- Support for converting to 32bit .wav files.
- User Guide in Greek (no photos translation yet).
- Improved Gapless playback and removed Gapless duration (not needed anymore).
- Playlist paths (when opened/saved) are remembered independently than the last used path.
- More cleanup of Lyrics' text.
- Sometimes some temp files were left over.
- 4.5.2.0
Added:- Ctrl+clicking any bar in Spectrum Analyzer, shows a tooltip with its frequency.
- Optimized Waveform data creation.
- 4.5.1.1
Changed:- Spectrum Analyzer can now have any of 24, 32, 40, 48 or 56 bars.
- Could not download lyrics.
- 4.5.0.2
Added:- A new waveform display and a Visualizer with three different modes!.
- Spectrum Analyzer.
- Osciloscope.
- Spectrogram.
- Can now drag YouTube tracks from the "Find Tracks" window to the Playlist.
- Alt+click Stop button stops track with fade out.
- Shift+click Stop button stops playback after track ends, and selects the next one.
- Disabled the preview of YouTube tracks when Truncating/Splitting.
- Saving a Playlist allowed fobiden characters in the filename.
- Some times the "Recent tracks" menu didn't close after clicking on a track.
- A new waveform display and a Visualizer with three different modes!.
- 4.4.3.0
Added:- Delete track from "Recent Tracks" with right click menu action.
- Preference option to enable/disable Autoplay for a Track/Playlist that is opened with KataLib.
- Autoplay track opened with KataLib only if the Playlist is empty.
- Better handling of temporary files.
- 4.4.2.1
Added:- "Multi Edit Metadata" dialog can now also change the Titles of the selected tracks
- Some glitches with the preview of a sliced track.
- The modification time of a track that had its cover edited was changed, although this was disabled in the Preferences.
- 4.4.1.2
Added:- We can also download auto-generated subtitles (eng/ell) from YouTube.
- No multi-video download from YouTube anymore because of changes in YouTube streams.
- Setup wrongly wanted to uninstall previous version, to install v5.x (this is not needed yet, since we're still on v4.x..).
- Setup was wrongly installed as x64 bit program.
- The En-US/En-UK subtitles were not listed for download.
- 4.4.0.0
Added:- New User guide tab on the "About" window (also online).
- "Add Tracks" gives the option to load local files or enter a YouTube url (a single video or a playlist).
- New, scrollable Recent played tracks menu.
- No context menu when the playlist was empty.
- Could not add again a YouTube link to Playlist if it was added already.
- Wrong next track if re-arranged the playlist after starting playback.
- 4.3.17.0
Added:- Compact View window snapping.
- Updated YouTube library.
- 4.3.16.1
Added:- .oga Ogg/Opus Audio (lossy) support.
- Updated YouTube library.
- Custom skin was not remembered.
- 4.3.15.0
Changed:- Updated YouTube library.
- 4.3.14.0
Added:- Fast search covers button for selected tracks when in MultiEdit Metadata.
- DownSize cover for all selected tracks at once.
- Opening a Playlist file by double clicking, now plays the saved last playing track, if the list is empty.
- Pressing the Esc key while focused in List/Properties panel in Compact View closed that panel.
- Updating YouTube Collections did not work.
- Clearing a Playlist in Compact View did not cleared the Playlist Title.
- Gapless playback did not work some times.
- 4.3.11.0
Changed:- Updated YouTube library.
- Click and drag the Compact View was not working as expected.
- YouTube ads made searcing for YouTube lists to hang sometimes.
- 4.3.10.0
Fixed:- YouTube search sometimes reurned no results.
- 4.3.9.0
Fixed:- Google image search was broken.
- Smaller bug fixes.
- 4.3.8.0
Added:- Converting to m4a/aac can now produce a striped .aac file (instead of .m4a).
- Right-click option to remove all missing links from the PlayList.
- While crossfading tracks its now possible to stop the player.
- Problems with crossfades if the track's duration was smaller than the crossfade's duration.
- Some problems with .m3u and .m3u8 files (WinAmp Playlists).
- 4.3.4.3
Added:- Recent played tracks menu.
- A field that displays/edits the Playlist's name.
- Support for converting (not playback) of ".dfs" Direct Stream Digital audio files.
- Missing YouTube tracks (due to their removal or no network connection) are no longer automatically removed from the PlayList.
- "Import/Export/Save" Collection has been renamed "Open/Save/Save + tracks".
- Tracks can now also be splitted using a .txt file with the "hh:mm:ss" time format.
- New icon for the YouTube tracks in Playlist, to reflect the presence of downloaded audio stream.
- Wrong scrolling of the playlist while in Compact mode.
- Toolbar was shown Library button while the Library was hidden.
- 4.3.1.0
Changed:- Updated yt-dlp library to 2023-12-30 version.
- The Fade on stop max duration was increased from 10 to 20 secs.
- Stop after current playing track was broken.
- If Gapless mode was on, the CrossFade's fade out was wrong.
- 4.3.0.0
Added:- A poor man's Gapless playback option in Preferences.
- Stop after current playing track (Shift+Spacebar).
- Middle click anywhere toggles Play/Pause for the current track. Middle click a track toggles Play/Pause for this track.
- New mouse-wheel functions.
- Ctrl+Wheel zooms in/out the rows.
- Shift+Wheel in Playlist selects multiple tracks.
- Alt+Wheel in Playlist changes volume.
- Updated yt-dlp library.
- Many code changes/re-writes under the hood.
- Droping a file from Explorer ontop of the currently playing track made the next playing track behave problematically.
- Moving selection (the currently selected track) with arrows, produced various problems.
- Changing tracks using the arrows while in MetaData Editor, displayed the wrong Cover.
- 4.2.16.0
Changed:- Downgraded yt-dlp library because of compatibility issues.
- Some small bugs.
- 4.2.15.0
Added:- Compact View can now Save/Restore a Layout of its windows sizes and positions (right-click > View > Layout).
- Updated yt-dlp library.
- 4.2.14.0
Changed:- Drag'n'Drop comunication between Playlist and other apps has been improved. (Dropping tracks from Playlist to Explorer now copies the files and dropping YouTube tracks to a browser now opens the links).
- Google image search and YouTube playlists were not working due to Google changes.
- Rare MP3 user tag's content prevented Metadata Editor from opening.
- 4.2.11.0
Changed:- Using the "/" charackter to the renaming field of Metadata editor can now create directories too.
- Small internal bug the might lead to bigger temporary directory.
- 4.2.10.0
Changed:- The "-" caracter is also allowed in the track number field of the metadata edit dialog (e.g. 8-12) along with "ABCD" characters for LP sides (e.g. A2, B4..).
- Previous version of KataLib intoduced a bug that prevented the changing of the track nunber to anything that ended to 0 (e.g. 10, 20..).
- 4.2.9.0
Changed:- Layouts can now be deleted/updated from the drop-down menu too.
- The "/" caracter is allowed in the track number field of the metadata edit dialog (e.g. 4/12).
- Opening multiple tracks/files to edit their metadata now checks if some of their tags are the same and shows them.
- When editing multiple tracks/files and a new cover was downloaded from net, it was not updated after closing the dialog with the OK button as it should.
- Don't show Youtube DASH video streams for download.
- Renaming a great number of files at once, sometimes missed a leading 0 of the track number.
- 4.2.6.0
Changed:- Updated yt-dlp library.
- Some YouTube Previews could not be played/saved.
- Right clicking on empty Playlist did not produce a menu in some systems.
- 4.2.4.0
Fixed:- Joining files did not start.
- Minimizing the app (in Full View), caused the Drop-zone to not be visible.
- 4.2.2.0
Added:- In Compact View, Ctrl+click on cover opens Cover Preview.
- Clicking the "Download Cover" button in "Edit Metadata" dialog, opens the dialog to search for cover and also automatically starts searching.
- Better dialog alighnment in Compact View.
- 4.2.0.0
Added:- Option to normalize (set maximum value to 100%) the converted audio.
- Option to keep (or not) the aspect ratio when downsizing a cover image downloaded from the internet.
- Menu option to downsize an already existing Cover image.
- There is an info dialog if we add a folder that already exists in Library.
- When changing tags for multiple files and one of them was playing, the app froze.
- Library might display some control columns that should be hidden.
- Better .flac cover detection.
- Some smaller cosmetic fixes/changes.
- 4.1.1.0
Added:- Support for different File Mangers (to selecta a track file in the File System.
- 4th Custom editor in the context menu of a track.
- "Set as Folder Cover" will now change the folder's icon.
- Pressing Enter/Return after Progress is finnished, will now close the dialog.
- Some restructuring into the Preferences panel.
- Better handling of re-launching the app when it's already open.
- Updated MediaInfo library.
- Sometimes, double sound when processing ends.
- Moving the position slider and then hit play, acts as expected.
- When deleting a paused track, the pause animation does not stop.
- No default paths in "Settings" > "Paths".
- Various small bugs when there was only one track in Playlist.
- 4.0.8.0
Changed:- Filename of a Playlist track can be edited from the Metadata window, like the Library tracks.
- Renaming a track and then copying it was using the old name.
- Some cosmetic changes.
- "Send log" to developer was not working.
- Preview image in "Download Cover" window was not working.
- 4.0.5.0
Added:- Some new cross-fade curves (Lo/lin & Lo/hi).
- In Compact View, double-clicking the selected track's title opens it in explorer.
- New blank cover image with KataLib logo.
- Double-clicking a YouTube track downloaded the audio but it didn't start playback.
- Preview image in "Download Cover" window was not working.
- 4.0.2.0
Changed:- Showing Playlist numbers for tracks in the "Find Tracks" from Playlist dialog.
- Go to previous track by keyboard shortcut was selecting two tracks.
- Could not get some YouTube links.
- 4.0.0.0
Added:- Option to hide Playlist numbers/Icons.
- Patterns that were used to rename file are now remembered.
- This is a major release since Python was updated from 2.7 to 3.8 and the
underline libraries are updated from Pyside and Qt4 to Pyside2 and Qt5.
Because of that the Windows XP support is dropped. - Right click Playlist header menu now shows Sorting and View actions.
- Separate action to save the current Playlist with the actuall track files.
- Naturally (e.g. 2 is before 11) sorted paths when sorting Playlist by path.
- Multi-track lyrics download now shows progress and can be stopped with "Esc".
- While playing, KataLib was displaying a wrong (the previous) title at the taskbar button and the tray icon tooltip.
- Sometimes, some new lines where missing from the Lyrics that were fetched.
- The file selector openned when pressing the "Files" button even if no tracks were selected.
- Version history older than 4.0.0.0