Inpainting and Editing

Regenerating one bar instead of everything is easy to ask for and hard to make seamless.

Related

DAWPhraseMIDI Protocol

The problem

Regenerating the whole thing throws away the parts you already approved. Inpainting changes one short region and leaves the rest alone. Asking is easy; the seam is hard. The new fragment usually comes from a different performance, so level, reverb and dynamics may not match, and the join sounds like a player swap. The larger the selection, the closer you are to regenerating everything.

How it works

A seam hides when the boundary lands somewhere musical. Bar lines, phrase ends and chord changes are safer than the middle of a bar. Give the tool more context than the selection, a bar on each side, so it knows what it is joining. Audio inpainting replaces tails and reverb along with the notes, MIDI inpainting replaces only notes, so the first seam lives in the spectrum and the second in timing and dynamics. A selection that contains one whole harmonic progression behaves better than half a chord.

Practice

Align the selection to bar lines in the DAW and leave a beat of overlap on each side. After generating, listen to the new fragment alone to see whether it solved the problem, then listen to two seconds across the join. Match level with gain, and fix phase or tone with a short crossfade. If the same seam problem appears three times, the context was too small; widening the range saves more time than more nudging. Log the selection and context length so the next repair starts from a known point.

What to listen for

In Haydn's rondo, the theme returns almost identically each time, so replacing one bar exposes the seam at once. In the four-part chorale, whether the substituted chord still follows the same voice leading or suddenly moves in parallel. In the Kesh jig, whether accents land where they did before half a phrase was replaced. In the 116 BPM jazz-funk fill, whether the cymbals turn bright at the join.

Sources

• 局部重绘的边界选择，依音频编辑实践通识核对，未抄原文
• 交叉淡化与增益匹配的做法，依混音通识核对，未抄文本

Used for fact-checking only; all prose is original.