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netflixy_preserve_audio_main_subtitle_intent_legacy_subhd

Generated from stock preset pack netflixy_main_subtitle_intent.

Dependencies

Tool Needed Why
ffmpeg required scenario execution, encode/transcode, and mux packaging
ffprobe required criteria probing and stream/metadata inspection

E2E Verification

This profile is considered e2e-verified when its mapped suites pass in CI.

Suite What it proves Toolchain version report
tests/e2e/run_profile_actions_e2e.sh action-level output behavior, guardrails, and subtitle-intent pathways tests/e2e/.reports/latest/run_profile_actions_e2e_toolchain_versions.md

Intent

This profile converts candidates into streaming-friendly HEVC outputs while preserving mainline viewing intent where feasible.

What It Optimizes For

  • practical bitrate efficiency with a consistent HEVC target
  • preserve all audio streams by default when packaging permits
  • preserve one director-intent "main subtitle" when detected
  • conditional container selection: MKV when subtitle intent applies, fragmented MP4 otherwise
  • for legacy sub-HD intake: optional deinterlace and persistent black-bar auto-crop

Input Envelope

Field Value
Codec any
Bit depth any
Color space any
Min resolution 320x240
Max resolution 1279x719

Scenario Map

Scenario Command
RES_JUST_RIGHT transcode_hevc_legacy_main_subtitle_preserve_profile.sh $vfo_input $vfo_output
ELSE profile_guardrail_skip.sh $vfo_input $vfo_output netflixy_legacy_subhd_guardrail_requires_320x240_to_1279x719_input

Runtime Behavior

  • Scenario RES_JUST_RIGHT uses action script transcode_hevc_legacy_main_subtitle_preserve_profile.sh.
  • Scenario ELSE uses action script profile_guardrail_skip.sh.

Action summary from transcode_hevc_legacy_main_subtitle_preserve_profile.sh:

  • Always preserves audio streams with stream copy.
  • Selects one "main subtitle" when it appears director-intent oriented:
  • priority: forced english -> forced untagged/unknown -> optional default english.
  • non-english forced tracks are intentionally skipped.
  • Preserves dynamic-range signaling for HDR workflows by default:
  • applies metadata-repair defaults when source tags are incomplete.
  • Optionally applies deinterlace when input is interlaced (default: auto).
  • Optionally applies stable black-bar auto-crop for persistent bars.
  • If selected subtitle is bitmap-based, crop is disabled for subtitle placement safety.
  • If a main subtitle is selected, output container is MKV for reliable subtitle preservation.
  • If no main subtitle is selected, output container is stream-ready MP4:
  • fragmented MP4 with init/moov at the start.

Operator knobs from transcode_hevc_legacy_main_subtitle_preserve_profile.sh:

  • VFO_MAIN_SUBTITLE_INCLUDE_DEFAULT=1 # include default english subtitle when no forced track exists
  • VFO_ENCODER_MODE=auto|hw|cpu
  • VFO_MP4_STREAM_MODE=fmp4_faststart|fmp4|faststart
  • default: fmp4_faststart
  • VFO_LEGACY_DEINTERLACE=auto|always|off
  • default: auto
  • VFO_LEGACY_AUTOCROP=1|0
  • default: 1
  • VFO_LEGACY_CROP_SAMPLE_SECONDS=3
  • VFO_LEGACY_CROP_DETECT_LIMIT=24
  • VFO_LEGACY_CROP_MIN_PIXELS=8
  • VFO_DYNAMIC_METADATA_REPAIR=1|0
  • default: 1
  • VFO_DYNAMIC_RANGE_STRICT=1|0
  • default: 1
  • VFO_DYNAMIC_RANGE_REPORT=1|0
  • default: 1

Starting Inputs And Expected Outputs

Aspect What this profile expects / does
Starting containers mkv, mp4, mov, mxf (anything ffmpeg can demux)
Required codec envelope any / any-bit / any
Required resolution range 320x240 to 1279x719
If criteria do not match candidate is routed to another profile or skipped
If criteria match scenario order is evaluated and first match executes
Output intent conditional: MKV when main subtitle intent is detected, otherwise stream-ready MP4 (fragmented + init/moov at start by default)

Flow

flowchart LR classDef gate fill:#fff7ed,stroke:#f59e0b,color:#7c2d12,stroke-width:1.5px; classDef stage fill:#e0f2fe,stroke:#0284c7,color:#0c4a6e,stroke-width:1.2px; classDef output fill:#dcfce7,stroke:#16a34a,color:#14532d,stroke-width:1.2px; classDef skip fill:#f3f4f6,stroke:#6b7280,color:#1f2937,stroke-width:1.2px; A[Input candidate: mkv / mp4 / mov / mxf]:::stage --> B[Probe codec bits color resolution]:::stage B --> C{Matches profile criteria envelope?}:::gate C -->|No| Z[Handled by other profile or guardrail skipped]:::skip C -->|Yes| D{Evaluate scenarios in order}:::gate D --> E[Execute subtitle-intent action]:::stage E --> P[Optional lane-specific pre-processing]:::stage P --> F{Main subtitle intent detected?}:::gate F -->|Yes| G[Encode HEVC + preserve audio + preserve main subtitle]:::stage G --> H[Emit MKV output]:::output F -->|No| I[Encode HEVC + preserve audio]:::stage I --> J[Finalize fragmented MP4 + init/moov at start]:::stage J --> K[Emit MP4 output]:::output

What This Profile Does Not Do

  • It does not normalize frame rate; source cadence/timebase is preserved by default.
  • It does not transcode audio for target-device compatibility by default.
  • It does not guarantee every input audio codec is valid for every selected output container.
  • It does not semantically understand subtitle meaning; subtitle selection is metadata and flag driven.
  • It does not OCR or convert bitmap subtitles to text subtitles.
  • It does not generate ABR ladders (HLS/DASH); output is a single-file artifact.
  • It does not certify playback on every device model; profile criteria are compatibility-oriented guardrails.
  • It does not enforce PSNR/SSIM/VMAF thresholds unless quality checks are explicitly enabled and configured.
  • It does not invent missing HDR/DV essence; metadata repair is heuristic and can be disabled.
  • It depends on source integrity and toolchain support for DV/HDR retention; strict mode may fail instead of silently downgrading.

Source

  • Preset file: services/vfo/presets/netflixy_main_subtitle_intent/vfo_config.preset.conf
  • Generated by: infra/scripts/generate-profile-docs.sh