This enumeration determines the type of barcode found on a page.
| IG_TW_BT_2OF5DATALOGIC | 2OF5DATALOGIC |
| IG_TW_BT_2OF5IATA | 2OF5IATA |
| IG_TW_BT_2OF5INDUSTRIAL | 2OF5INDUSTRIAL |
| IG_TW_BT_2OF5INTERLEAVED | 2OF5INTERLEAVED |
| IG_TW_BT_2OF5MATRIX | 2OF5MATRIX |
| IG_TW_BT_2OF5NONINTERLEAVED | 2OF5NONINTERLEAVED |
| IG_TW_BT_3OF9 | 3OF9 |
| IG_TW_BT_3OF9FULLASCII | 3OF9FULLASCII |
| IG_TW_BT_CODABAR | CODABAR |
| IG_TW_BT_CODABARWITHSTARTSTOP | CODABARWITHSTARTSTOP |
| IG_TW_BT_CODE128 | CODE128 |
| IG_TW_BT_CODE93 | CODE93 |
| IG_TW_BT_EAN13 | EAN13 |
| IG_TW_BT_EAN8 | EAN8 |
| IG_TW_BT_MAXICODE | MAXICODE |
| IG_TW_BT_PDF417 | PDF417 |
| IG_TW_BT_POSTNET | POSTNET |
| IG_TW_BT_UCC128 | UCC128 |
| IG_TW_BT_UPCA | UPCA |
| IG_TW_BT_UPCE | UPCE |