CD Rip Log

CD 抓轨日志 (CD Rip Log) is a text or structured file created by digital audio ripping software to record the reading process and verification results. Programs such as Exact Audio Copy, XLD, and dBpoweramp use different fields and formats, but these logs typically specify which disc was read, the type of optical drive and settings used, and whether errors occurred on each track or if matches were found in an external database.

The log may include the software version, optical drive model, interface, read mode, cache handling, C2 settings, read offset, overread capability, pre-gap detection, and output format. The track-by-track section often lists start and end positions, peak levels, extraction speed, CRC, suspicious positions, AccurateRip confidence, and final status. If an encoder such as FLAC is invoked after ripping, command-line and compression parameters may also be written to the log; however, these pertain to a different stage than the accuracy of the front-end reading. An identical CRC indicates that the corresponding algorithm produced the same checksum for the compared data, which can be used to verify whether a track was read multiple times or if the track file has changed. Different software, log versions, or boundary handling methods may use different CRC algorithms and exclusion ranges; therefore, values cannot be directly compared across different programs without considering the context of the program that generated them. AccurateRip results, on the other hand, are derived from its specified verification process and database and should not be conflated with the software’s own “Test CRC.”

Logs can help reproduce settings and pinpoint issues, but since plain text can be edited, they cannot serve as a tamper-proof source of evidence on their own. Even if the log is authentic, “No errors occurred” only reflects the scope of the software’s detection; errors such as C2 configuration issues, caching, fixed interpolation, unread leading or trailing samples, and subsequent file replacements may still go undetected. Combining logs with audio file checksums, CUE sheets, and database verification provides a more complete picture of a rip.

Re-encoding, modifying tags, or replacing cover art typically does not automatically update the original rip log. If the file’s PCM content remains unchanged, certain audio checksums may still match; however, if the log only records the file-level hash of the WAV at the time of ripping, changes to the container format may render the hash invalid. Logs should be regarded as a historical record of a specific operation, rather than real-time metadata that automatically synchronizes with media files.