REC file format - entropia/tip-toi-reveng GitHub Wiki

This page is meant to collect information about the *.rec files, that the 2018 TipToi pen creates when recording with the built-in microphone.

The files appear to be named using the following schema (relative to the root directory of the TipToi pen):

./‹productId›book/RecSlot‹slotNumber›.rec

In this schema ‹productId› is the ID of the "product" (book/game/…) which you used to record the file with.

‹slotNumber› is a 4-digit number to distinguish the recordings in one product. It seems that one slot number can be assigned to an arbitrary OID. Normally there is one OID that always records a certain slot and one other OID that plays that slot. The lowest slot number found in a Ravensburger book is 0001 (see examples)

Examples

  • "Die verrückte Weltreise"
    • ./129book/RecSlot0001.rec (the wizard on the first page, recorded by OID 3218, played back by OID 3219)
    • ./129book/RecSlot0007.rec (the man in the ear-costume on the second page, recorded by OID 3248, played back by OID 3249)
    • ./129book/RecSlot0003.rec (the bird on the first page, recorded by OID 3226, played back with higher pitch and three times by OID 3227)
    • ./129book/RecSlot0013.rec (the clown on the second page, recorded by OID 3286, played back by 3287 followed by the clown laughing)

The file format

The files are WAV files xor-ed with the byte 0x6a. More specifically the WAV files are encoded using PCM (signed, little-endian), a sample rate of 16 kHz (exception: in "Die verrückte Weltreise", the recordings made for the blue bird have a sample rate of 8 kHz, probably has to do with the high-pitched playback), 16 bits sample size, mono.

File conversion

  • Online tools

    • CyberChef allows to convert REC files can to WAV files (and vice versa).
    • ttwebhelpers allow to convert REC files to WAV, and MP3. (Decoding happens directly in the browser and REC files do not get uploaded to the Internet.)

  • Offline tools

    • ttbox offers a convert-rec command to convert REC files to WAV, and MP3.