Melody harmonization, which involves generating a chord progression that complements a user-provided melody, continues to pose a significant challenge. A chord progression must not only be in harmony with the melody, but also interdependent on its rhythmic pattern. While previous neural network-based systems have been successful in producing chord progressions for given melodies, they have not adequately addressed controllable melody harmonization, nor have they focused on generating harmonic rhythms with flexibility in the rates or patterns of chord changes. This paper presents AutoHarmonizer, a novel system for harmonic density-controllable melody harmonization with such a flexible harmonic rhythm. AutoHarmonizer is equipped with an extensive vocabulary of 1,462 chord types and can generate chord progressions that vary in harmonic density for a given melody. Experimental results indicate that the AutoHarmonizer-generated chord progressions exhibit a diverse range of harmonic rhythms and that the system's controllable harmonic density is effective.

翻译：旋律和声化，即生成与用户提供的旋律互补的和弦进行，仍是一项重大挑战。和弦进行不仅需要与旋律和谐共存，还必须与其节奏模式相互依存。虽然先前基于神经网络的系统在根据给定旋律生成和弦进行方面取得了成功，但它们未能充分解决可控的旋律和声化问题，也未能关注以灵活的和弦变化速率或模式生成和声节奏。本文提出AutoHarmonizer，一个新颖的、具备灵活和声节奏的、可控制和声密度的旋律和声化系统。AutoHarmonizer配备了包含1,462种和弦类型的广泛词汇表，能够为给定旋律生成和声密度各异的和弦进行。实验结果表明，AutoHarmonizer生成的和弦进行展现出多样化的和声节奏，并且系统的可控制和声密度是有效的。