FL007 Incorrect SD Card Serial Number Encoded In Log File

Incorrect SD Card Serial Number Encoded In Log File #

Problem ID Manufacturer Affected Firmware Affected Hardware Status
FL007 Frontier Labs 3.30 BAR-LT Minor problem

Within the Vorbis Comment section of FLAC files, Frontier Labs identify the SD Card CID, represented as a 16-byte hexadecimal string. The SD Card serial number can be found in bytes 10-13 of that hex string.

On five test recordings made using different SD cards there seems to be a bug in which the SD Card serial number from the log file isn’t matching the serial number encoded into the CID. As shown in the table, the bytes are matching except for the two most significant bytes in the CID serial number (the serial number from the log file is given in decimal and has been converted).

It appears the value in the log file is incorrect.

This website was used to extract the values of the CID and double check the decoded values.

We exracted values from the log files, and headers, and compared them:

(A) Recording (B) Log file serial number (C) SD card CID (D) serial from CID (hex) =MID(C3,19,8) (E) serial from CID (dec) =HEX2DEC(D3) (F) simulated problem =HEX2DEC( RIGHT(D3,6))
Test Recording 1 8041328 035344534431323885437AB37001480F 437AB370 1132114800 8041328
Test Recording 2 11217428 03534453443132388588AB2A140148D1 88AB2A14 2292918804 11217428
Test Recording 3 9090564 035344534431323885458AB604014809 458AB604 1166718468 9090564
Test Recording 4 4774740 0353445344313238854448DB54014801 4448DB54 1145625428 4774740
Test Recording 5 14793234 03534453433132388046E1BA12013AFB 46E1BA12 1189198354 14793234

In the simulated problem column we can see that by trimming the hexadecimal serial value (using the RIGHT) function we can simulate the values found in the log file.

Status of the problem #

Minor issue, the correct data is in the header for the files.

Waiting for reproduction of problem from QUT Ecoacoustics

Status with vendor #

We’ve asked FL for comment, they have not yet responded.

Effects of the problem in common tools #

No effect - the CID information is currently not used in any tools we know of; EMU may be able to detect and repair this problem if the sensor log file is found near the files.

Example files #

https://connectqutedu.sharepoint.com/sites/QUTEcoacousticsAnon/Shared%20Documents/Forms/AllItems.aspx?id=%2Fsites%2FQUTEcoacousticsAnon%2FShared%20Documents%2Fknown%2Dproblems%2Ffrontier%5Flabs%2FFL007