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Sink (Core) Stages

Sink core stages are the endpoints of a decode-orc pipeline. They consume processed data from upstream stages and write results to disk or hardware. Unlike transform stages, sink stages do not produce outputs that can be connected further downstream.

A pipeline may contain multiple sink stages in parallel, allowing the same processed stream to be written in different formats or to different destinations.

Sink core stages are used to:

  • Write final video outputs (TBC + metadata)
  • Export auxiliary data such as audio, EFM, or closed captions
  • Output video directly to hardware for monitoring or capture
  • Export intermediate data for inspection or external tools

Analogue Audio Sink
Stage id audio_sink
Stage name Analogue Audio Sink
Connections 1 input → no outputs
Purpose Export analogue audio to a WAV file

Use this stage when:

  • Your source contains analogue audio tracks
  • You want to export audio independently of video output
  • You want to inspect or process audio externally

What it does

This stage extracts analogue audio samples from the incoming stream and writes them to a standard WAV file. Audio remains synchronised to the processed video timeline.

Parameters

  • output (string)
    • Path to the output WAV file.
    • Required.

Notes

  • Digital audio (if present) is not handled by this stage.
  • Audio stacking or selection must be performed upstream (e.g. via stacker).

Chroma Sink
Stage id chroma_sink
Stage name Chroma Sink
Connections 1 input → no outputs
Purpose Export decoded chroma information for inspection or external processing

Use this stage when:

  • Debugging or validating chroma decoding
  • Inspecting chroma independently of luma
  • Feeding chroma data into external analysis tools

What it does

This stage writes chroma samples to disk in a raw format suitable for offline inspection or research workflows.

Parameters

  • output (string)
    • Path to the chroma output file.
    • Required.

Notes

  • The exact chroma format depends on the upstream decoding stages.
  • This stage is primarily intended as a diagnostic / research tool.

Closed Caption Sink
Stage id cc_sink
Stage name Closed Caption Sink
Connections 1 input → no outputs
Purpose Extract and write closed-caption (CC) data

Use this stage when:

  • Working with NTSC sources containing Line 21 closed captions
  • You want to extract captions for archival or conversion
  • You want to inspect CC data independently of video

What it does

This stage scans the incoming video stream for closed-caption data and writes decoded caption packets to a file.

Parameters

  • output (string)
    • Path to the closed-caption output file.
    • Required.

Notes

  • CC data must be preserved upstream (e.g. not masked out).
  • Masking Line 21 before this stage will prevent caption extraction.

EFM Decoder Sink
Stage id efm_sink
Stage name EFM Decoder Sink
Connections 1 input → no outputs
Purpose Decode EFM t-values to audio WAV or ECMA-130 binary sector data

Use this stage when:

  • Extracting digital audio from a LaserDisc source as a WAV file
  • Extracting ECMA-130 data sectors from a LaserDisc source
  • You want the fully decoded output of the EFM stream rather than the raw t-values

What it does

This stage accumulates EFM t-values from the incoming stream and runs the full EFM decode pipeline, producing either a standard PCM audio WAV file or ECMA-130 binary sector data depending on the chosen decode mode.

Parameters

  • output_path (string)

    • Path to the decoded output file. Use .wav for audio mode or .bin for data mode.
    • Required.

  • decode_mode (string)

    • Selects the decode target. audio (default) produces a WAV or raw PCM file; data produces ECMA-130 binary sector data.
    • Allowed values: audio, data.
    • Default: audio.

  • no_timecodes (boolean)

    • Disable timecode verification (early discs did not include time-codes in the EFM and will fail to decode without this option).
    • Applies to both audio and data modes.
    • Default: false.

  • audacity_labels (boolean)

    • Write an Audacity label file alongside the audio output indicating the position of chapters as well as any missing samples.
    • Applies only in audio mode.
    • Default: false.

  • no_audio_concealment (boolean)

    • Disable interpolation-based audio error concealment.
    • Applies only in audio mode.
    • Default: false.

  • zero_pad (boolean)

    • Zero-pad the start of audio output so the sample starts from 00:00:00.0 relative to the first valid time-code.
    • Applies only in audio mode.
    • Default: false.

  • no_wav_header (boolean)

    • Output raw PCM samples without a WAV file header.
    • Applies only in audio mode.
    • Default: false.

  • output_metadata (boolean)

    • Write a bad-sector map metadata file alongside the sector output. This file contains the number of any missing or corrupt sectors.
    • Applies only in data mode.
    • Default: false.

  • report (boolean)

    • Write a detailed decode statistics report file.
    • Default: false.

Notes

  • The source stage must supply an EFM file; the pipeline will abort if no EFM data is present in the incoming stream.
  • Audio and data decoding are mutually exclusive — select decode_mode before enabling mode-specific parameters.
  • EFM stacking or correction should be performed upstream before this stage.

LD Sink
Stage id ld_sink
Stage name LD Sink
Connections 1 input → no outputs
Purpose Write an ld-decode-compatible TBC and metadata output

Use this stage when:

  • Producing final archival-quality outputs
  • Feeding results back into the ld-decode ecosystem
  • Preserving full metadata, audio, and disc data

What it does

This stage writes:

  • A .tbc file containing processed video fields
  • A metadata database compatible with ld-decode
  • Associated audio and EFM data if present

The output can be used directly with existing ld-decode tools.

Parameters

  • output (string)
    • Base path for output files.
    • Required.

Notes

  • This is the most common “final output” sink stage.
  • All upstream corrections, stacking, and parameter overrides should be complete before this stage.

Raw EFM Sink
Stage id raw_efm_sink
Stage name Raw EFM Data Sink
Connections 1 input → no outputs
Purpose Write raw EFM t-values to a binary file

Use this stage when:

  • Archiving LaserDisc EFM t-values for later processing
  • Feeding raw EFM data into external decoding or analysis tools
  • Verifying EFM integrity after stacking or correction

What it does

This stage extracts raw EFM (Eight-to-Fourteen Modulation) t-values from the incoming stream and writes them to a binary file. The output contains only 8-bit unsigned integers representing valid t-values in the range 3–11, stored field by field with no headers or additional formatting.

Parameters

  • output_path (string)
    • Path to the output EFM file (raw t-values). Conventionally uses the .efm extension.
    • Required.

Notes

  • The source stage must supply an EFM file; the pipeline will abort if no EFM data is present in the incoming stream.
  • EFM stacking behaviour is controlled upstream (e.g. via stacker).
  • This stage does not modify or decode EFM data. Use the efm_sink stage to decode t-values to audio or sector data.

Notes on Sink Stages

  • Sink stages terminate pipeline branches.
  • Multiple sink stages may consume the same upstream output.
  • Sink stages do not alter timing or metadata beyond their specific export role.