Decrypt given data previously encoded with seed-ofb cipher algo. SEED in OFB (Output Feedback) mode, using feedback to convert the block cipher into a stream cipher. OFB mode was used with SEED to improve encryption for data streams. SEED-OFB is secure but considered outdated compared to AES. Our decryption process assumes the IV string is prepended in the encoded string during the encryption process. You can not decrypt and get the correct results if the IV or passphrase mismatch occurs between encryption and decryption process.