Inserting images into documents. An image source device is made active with an application used to create text in a document. An application programming interface (API) module is accessed from within the application. The API interfaces the application with a TWAIN module used for acquiring an image with the image source device. The API module is separate from the TWAIN module and isolates users from directly interacting with the TWAIN module. The application uses the API module for negotiating with the image source device to determine a set of image capture parameters that control the image source device when acquiring the image. Data representing the image is communicated from the image source device into the memory of a computer hosting the application used to create text so that the data representing the image is a portion of a document stored in the memory.