Apps Script library to convert between file types, including OCR for image to documents, with a huge repertoire of conversion combinations.
The Drive API offers a whole range of conversions between mimeTypes, but it’s a little fiddly to figure out exactly how. This library takes a file and an a desired output format and converts it for you. Sometimes, there’s not a direct route – for example if you need to convert a word file to a pdf, it first needs to get converted to a Google Doc, then to a Pdf. This library automatically works out and actions any intermediate conversions required.
For those who are unfamiliar MIME types (mimeTypes) is a standard way of identifying a file’s content type, such as text, image, or audio. The MIME type for a file is usually used by applications to determine how to open and display the file. Google Drive is able to convert various files, such as a MS Word document to Google Docs.
Sometimes there isn’t a direct route and this clever library from Bruce Mcpherson can help alleviate the pain. The library works by first checking if there is a direct route between the input and output file formats. If there is, it simply converts the file. If there is no direct route, the library will use the Drive API to first convert the file to a format that can be converted to the output format. For example, if you need to convert a Word file to a PDF, the library will first convert the Word file to a Google Doc, and then convert the Google Doc to a PDF.
Knowing what mimeType to use can be a bit of a challenge but you can also use the library to give a list of known types, or if you prefer a more readable list of Google Drive export MIME types.
Source: Convert any file with Apps Script – Desktop Liberation
Member of Google Developers Experts Program for Google Workspace (Google Apps Script) and interested in supporting Google Workspace Devs.