如何为 AI 视频添加对白和口型同步
学会用三种方式为 AI 视频添加对白和口型同步:原生台词、单独配音或画外音。然后像导演演员一样导演合成语音。
在这一课中你将学到
- AI 视频中处理对白的三种方式:原生对白、单独配音和画外音
- 如何在提示词中写一句原生台词:台词内容、语言和语气
- 如何通过角色的 Add Voice 按钮和音频节点,把声音文件导入 ScreenWeaver
- 如何用一句书面的表演提示来导演合成语音
- 为什么画外音往往是最简单、也最有电影感的方式
- 克隆真人声音的同意规则
台词是 AI 电影最容易出问题的地方:声音不对,节奏不对,口型对不上。这一课讲解 AI 视频中处理对白的三种方式,以及各自适用的场合。原生对白随画面一起生成,人声、口型动作和环境音都在同一条素材里,The Photo 中 Thomas 的那句台词就是这样做出来的。单独配音先用文字转语音模型制作,让你掌控表演和节奏;在 ScreenWeaver 中,它会进入一个音频节点,可以发送给支持音频输入的视频模型。画外音完全不需要口型同步,Lost Garden 就用了这个思路,片中的骑士没有脸,也没有嘴。你还会学到如何用一句表演提示来导演合成语音,让每个角色听起来始终是同一个人,以及遵守声音克隆的同意规则。
完整文字稿
英语旁白的文字稿。
0:04Spoken lines are where AI films break most often – the wrong voice, the wrong timing, lips that don't match. In this lecture you'll learn the three routes for dialogue, when to use each one and how to direct a synthetic voice like an actor.
0:19Route 1 – native dialogue, generated with the picture. Some video models produce the voice, the lip movement and the ambience in the same take. That's how Thomas' line in the photo was made. The words are in the prompt, in quotes, with the language and the delivery, softly. Keep native lines short, one or two sentences, and keep the speaker clearly in frame.
1:02Route 2 – a separate voice, then the picture. You generate the voice first, with a text -to -speech model, so you control the performance and the timing, then the voice drives the video. In Screenweaver, a character's story element has an Add Voice button. It creates an audio node, where you upload the voice file, and that audio can be sent as a reference to the video models that accept audio. Dedicated lip -sync tools exist, too, outside the app, for shots that need frame -perfect sync.
1:31Note that the app doesn't generate voices itself – you bring the audio file. For a short film, a text -to -speech service with voice design is usually enough. For recurring characters, save the voice settings of each one, so every scene sounds like the same person.
1:46Whichever read you choose, direct the voice like an actor. Write an acting note in words – calm, grounded, a little tired, a southern English accent. The narration of this course was generated exactly that way, from a single voice and a single acting note. Keep one voice per character for the whole film. Generate a full scene in one pass, so the time beholds, and listen for mispronounced names before you move on.
2:12For Thomas's line, the note could be quiet, almost a whisper, a man who has rehearsed this sentence for days and still isn't ready to say it. A few words of direction change everything about a line.
2:26Route 3 – voiceover, with no lips to sync at all. An inner monologue, an orator, a letter read over images. It's the easiest route, and often the most cinematic one. Lost Garden uses a version of this idea. Its nights have no faces and no mouths, so there is nothing to sync. Emotion comes from posture, light and voice.
2:54One rule with no exception – never clone a real person's voice without their written consent. And check the rules of the platform where your film will play – some require you to disclose synthetic voices.
3:09Your exercise? Pick one line of dialogue from your script and produce it two ways – native, inside the generated shot, and as a separate voice with an acting note. Compare them in the cut. In the next lecture, we'll build the full soundtrack, edit the film and export it.