0.6.9 — Saving improvements and lyric reanalysis

Interface and settings

The bottom actions are organized into four buttons: Music Player / Save Analysis Results / Save Sheet Music / Save Audio.
A message under Save Analysis Results explains that reanalysis will not be needed next time.
Sheet Music and Performance menus are unavailable when no analysis information is selected. They become available after analysis completes or a project is loaded.
The Open Saved Sheet Music button was removed from the audio input screen. Open saved projects from the library.
The OpenAI API key, API model information, and Delete Saved API Key button were removed from settings. Existing credentials themselves are not deleted.
The AI lyric correction and detailed editing buttons were removed. Local lyric extraction and direct editing in the sheet music preview remain available.
Korean and English text is provided for the changed features.

Data that saves audio, lyrics, chords, and separation state together is classified as an analysis project.
Project deletion and recovery were added to the library.
Deleting a project moves its library folder to an internal trash area. Original audio outside the library is not deleted.

New analyses use a one-column layout by default. Previously saved layouts that were explicitly set are retained.
One-column sheet music with timing information is arranged into four bars per line. Meter information is used when available; otherwise, bars are estimated from BPM. Manually entered chord and lyric formats preserve their existing layout.
A two-column layout remains available.
Choose PDF or PNG from Save Sheet Music.
The default filename uses the current title in the preview, including edited titles. Characters that are not allowed in filenames are replaced.

Full mix: saves the full original audio mix as MP3. This is not a file mixed with the app-generated guitar or piano accompaniment.
Save without vocals (MR only): saves the separated backing track as MP3.
Save without MR (vocals only): saves the separated vocals as MP3.
Export is available from the Sheet Music and Performance screen, Music Player, and library.
Existing separation results are reused. If the audio has not been separated, the app asks you to separate it in Music Player first.
Choose the save location and filename. If conversion is canceled or fails, incomplete output does not overwrite an existing file.

An Add Lyrics / Reanalyze button was added above the sheet music preview.
Enter lyrics to align timing against the supplied text, or leave the field empty to run automatic lyric recognition.
Saved audio and valid separation results are reused. Chord detection is not run again.
Results are applied to the current sheet music and subsequently opened players. To keep them in the library as well, select Save Analysis Results.
Existing analysis data is retained if the operation is canceled or fails.
Entering only some lyrics may leave their timing unconfirmed because there is not enough alignment evidence. Supply as much of the song's lyrics as possible.

An update server, in-app update checks, and updates that download only changed files are not included.
This installer is also a full installer that includes the precision lyric model.

Lyrics, chords, meter, and start times are automatically estimated. Lyric recognition and alignment errors may remain.
Existing saved projects do not automatically change to use newly extracted results. Reanalyze the audio when needed, or use the lyric addition and reanalysis feature in 0.6.9.
Close LUA Music Studio before installation.
Component-based updates and a model reuse strategy are planned separately, targeting an actual release around 0.7.0.