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Module ltc

Module ltc 

Source
Expand description

Linear Timecode (LTC) reading and writing

LTC encodes timecode as an audio signal using biphase mark code (BMC). The audio signal contains 80 bits per frame:

  • 64 bits for timecode and user data
  • 16 bits for sync word (0x3FFD)

§Biphase Mark Code

  • Bit 0: One transition in the middle of the bit cell
  • Bit 1: Two transitions (at the beginning and middle)
  • Frequencies: ~1920 Hz (bit 0 at 30fps) to ~2400 Hz (bit 1 at 30fps)

§Signal Characteristics

  • Typically recorded at line level (-10 dBV to +4 dBu)
  • Can be read in forward or reverse
  • Can be read at varying speeds (0.1x to 10x nominal)

Modules§

decoder
LTC Decoder - Biphase Mark Code decoding from audio
encoder
LTC Encoder - Biphase Mark Code encoding to audio

Structs§

LtcReader
LTC reader
LtcReaderConfig
LTC reader configuration
LtcWriter
LTC writer
LtcWriterConfig
LTC writer configuration