You can use Shotstack to generate videos with a green chroma background and automatic subtitles from a text file. Shotstack offers an auto subtitle feature that generates subtitles automatically.
Alternatively, you can add captions manually by referencing an SRT or VTT file in your video timeline. The captions will be rendered directly onto the video.
You can fully customize the captions—adjusting font, color, size, positioning, and text formatting to match your desired style.
For more information, please refer to our documentation on captions and chroma key.