Module ltc_parser 

LTC (Linear Timecode) bit-level parser.

Parses the raw 80-bit LTC word into a LtcFrame containing a decoded Timecode. The parser operates on a slice of LtcBit values (i.e. clock-qualified biphase-mark decoded bits) and locates the sync word, then reconstructs the timecode fields.

SMPTE 12M LTC word layout (80 bits, LSB first per group)

• Bits 0-3: frame units
• Bit 4: user bit 1
• Bit 5: user bit 2 (actually these are user bit nibbles interleaved)
• Bits 4,6,10,12,18,20,26,28: user-bit nibble pairs
• Bits 8-9: frame tens + drop-frame flag (bit 10) + color-frame (bit 11)
• Bits 16-19: seconds units
• Bits 24-26: seconds tens
• Bits 32-35: minutes units
• Bits 40-42: minutes tens
• Bits 48-51: hours units
• Bits 56-57: hours tens
• Bits 64-79: sync word 0xBFFC (0011111111111101 in LS→MS order)

Structs

LtcFrame

A fully decoded LTC frame.

LtcParser

Parses raw LTC bit streams into LtcFrame values.

Enums

LtcBit

A single logical bit in an LTC data stream after biphase-mark decoding.

Functions

build_ltc_word

Helper: build an 80-bit LTC word from raw field values (for test construction).