TGRadioBooks
Why you cannot turn a password-protected PDF into audio
To turn a password-protected PDF into audio in TGRadio, you need an unprotected copy with an accessible text layer. The service does not support protected PDFs, even when you know the password. Start by checking whether the obstacle is file protection, scanned pages, or a combination of both.
Identify when the password is requested
Open the original file in your usual PDF reader. A password prompt before any pages appear indicates protection against opening the document. If pages are visible but copying is restricted, being able to read them does not establish that their text can be extracted. Check the document’s security properties if your reader provides them.
Describe what happens in plain language, for example: “The file opens after entering a password, and I can select text.” This helps the sender understand the issue. Putting the password in the book title or link field will not make the file suitable for import.
Request an authorized, unprotected copy
Contact the author, publisher, or person who supplied the document. Ask for a copy intended for your use without password protection, preferably containing selectable text. If the owner has the original text document, they may be able to prepare a suitable version from that source.
Explain that you need to extract the text for speech synthesis. For example, the sender might supply an authorized EPUB or FB2 edition instead. Check the title, language, and edition rather than relying on a similar filename.
Check whether the pages are scans
An unprotected copy only resolves the protection issue. Select several lines from an ordinary paragraph and paste them into a plain text editor. Repeat near the beginning, middle, and end: a PDF can contain both text pages and scans.
If you cannot copy any words, the page may be an image. TGRadio does not perform OCR. Request a text edition, or arrange text recognition outside the service where you are entitled to use the document that way. Proofread the recognized text before importing it.
Inspect the replacement before importing it
Close and reopen the replacement file. Check that it needs no password, copied paragraphs remain readable, and pages appear in the expected order. Compare at least one heading and its following paragraph with the original.
The import limits are 10 MB per file and 2 million extracted characters per book. Reducing file size does not remove protection or supply a missing text layer.
Test the corrected copy
Open Books, choose Upload a book, and add the prepared copy. After import, select the book and a voice, then press Play to start preparing audio. Listen to a familiar passage to confirm that you uploaded the intended edition.
If the unprotected document still fails, keep the exact error message. When contacting support, include the format, file size, and whether copied paragraphs are readable. You do not need to include the password to describe this problem.