Normalize Loudness File
normalize_loudness_fileCreates a new loudness-normalized audio/video derivative with FFmpeg, remeasures EBU R128, and retries renders when the target or true-peak ceiling is missed.
Instructions
Create a new loudness-normalized media derivative with FFmpeg, then remeasure that exact output using EBU R128. When the remeasured file misses the target or true-peak ceiling (AAC encoding can raise the true peak), it renders again with a lowered ceiling or offset target, up to max_attempts, keeps the best attempt and reports every attempt's measured I and TP. Never overwrites the input or an existing output file.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| input_path | Yes | Existing local audio or video file | |
| output_path | Yes | New output path; must not already exist | |
| target_lufs | No | Integrated loudness target from -70 through -5 LUFS (default: -16) | |
| max_attempts | No | Renders allowed when the remeasured output misses the target or true-peak ceiling, for example after AAC encoding raises the true peak (default: 2; 1 disables retries) | |
| tolerance_lu | No | Post-render integrated-loudness tolerance (default: 1 LU) | |
| idempotency_key | No | Optional client-chosen key (1-128 chars of A-Z a-z 0-9 . _ : -) for this intended edit. Pass a fresh key per edit and reuse it only when retrying that same edit, for example after a client-side timeout. A repeat with the same tool, key and arguments is not run again: while the first call is running it fails with IDEMPOTENCY_IN_PROGRESS (poll get_last_operations); after it finished it returns the original outcome marked replayed. A definite failure with nothing applied (receipt outcome not_applied) may be retried with the same key. Reusing a key with different arguments fails with IDEMPOTENCY_KEY_REUSED. Scoped to this MCP session (the stdio server process or one HTTP session) and held in memory only (200 keys, 1 hour); it does not survive a restart or reconnect. Read-only invocations are never deduplicated. | |
| max_true_peak_dbfs | No | True-peak ceiling from -9 through 0 dBFS (default: -1.5) | |
| expected_cep_target | No | Optional reviewed CEP sequence/clip identity and exact tick ranges. Checked before every generated command; UXP refuses this CEP-only guard. | |
| expected_project_path | No | Optional absolute saved-project path. Every generated CEP command refuses before its body when the active project differs or is unsaved. UXP commands refuse this CEP-only guard; local-only tools do not inspect Premiere. Omit to keep existing behavior. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| ok | Yes | Whether the tool completed successfully. | |
| data | No | Tool-specific result data when ok is true; on failure, diagnostic detail when the tool provides it. | |
| tool | Yes | The registered MCP tool name. | |
| error | No | Failure detail when ok is false. | |
| receipt | No | Versioned common mutation receipt; success never implies rendered verification. | |
| idempotency | No | Present when idempotency_key deduplicated this call: replayed is true when the original outcome was returned instead of running again. |