court-record-transcriber

name

court-record-transcriber

description

Development skill for CaseMark's Court Recording Transcriber - an AI-powered application for transcribing court recordings with speaker identification, synchronized playback, search, and legal document exports. Built with Next.js 16, PostgreSQL, Drizzle ORM, wavesurfer.js, and Case.dev APIs. Use this skill when: (1) Working on or extending the court-record-transcriber codebase, (2) Integrating with Case.dev transcription APIs, (3) Working with audio playback/waveforms, (4) Building transcript export features, or (5) Adding speaker identification logic.

Court Recording Transcriber Development Guide

An AI-powered application for transcribing court recordings with speaker identification, synchronized playback, search functionality, and professional legal document exports.

Live site: https://court-record-transcriber.casedev.app

Architecture

src/
├── app/
│   ├── api/recordings/         # API routes for recordings
│   │   ├── route.ts            # List, create recordings
│   │   └── [id]/
│   │       ├── route.ts        # Get, update, delete
│   │       ├── transcribe/     # Start transcription
│   │       └── export/         # Export endpoints
│   ├── upload/                 # Upload page
│   └── recording/[id]/         # Transcript viewer page
├── components/
│   ├── ui/                     # shadcn/ui components
│   ├── AudioPlayer.tsx         # Waveform + playback
│   ├── TranscriptView.tsx      # Transcript display
│   ├── SpeakerEditor.tsx       # Label speakers
│   └── ExportDialog.tsx        # Export options
└── lib/
    ├── db/
    │   ├── index.ts            # Database connection
    │   └── schema.ts           # Drizzle schema
    ├── casedev/                # Case.dev API client
    └── legal-vocabulary.ts     # Word boosting config

Core Workflow

Upload Audio → Transcribe → Identify Speakers → Review/Edit → Export
     ↓             ↓              ↓                ↓            ↓
  MP3/WAV     Case.dev API    Auto-detect      Sync playback   PDF/Word/
  M4A/etc     with legal      Judge, Atty,    click-to-seek   Plain text
              vocabulary      Witness, etc

Tech Stack

Layer	Technology
Frontend	Next.js 16, React 19, Tailwind CSS
Backend	Next.js API Routes
Database	PostgreSQL + Drizzle ORM
Audio	wavesurfer.js
Transcription	Case.dev Speech-to-Text API
Export	React PDF, docx library

Key Features

Feature	Description
Audio Upload	Drag-drop MP3, WAV, M4A, FLAC, OGG
AI Transcription	Case.dev API with legal vocabulary boosting
Speaker ID	Auto-detect speakers, customizable labels
Synced Playback	Click transcript line to jump to timestamp
Search	Find words/phrases with highlighting
Export	PDF, Word (.docx), plain text with legal formatting

Database Operations

PostgreSQL with Drizzle ORM. See references/database-schema.md.

Commands

npm run db:push      # Push schema (dev)
npm run db:generate  # Generate migrations
npm run db:studio    # Open Drizzle Studio

Core Tables

• recordings: id, filename, duration, status, audioUrl
• transcripts: id, recordingId, content (JSON), speakerMap
• utterances: id, transcriptId, speaker, text, startTime, endTime

Case.dev Integration

See references/casedev-transcription-api.md for API patterns.

Transcription Flow

// 1. Upload audio to Case.dev
const { audioId } = await uploadAudio(file);

// 2. Start transcription with legal vocabulary
const { jobId } = await startTranscription(audioId, {
  vocabulary: legalVocabulary,
  speakerDiarization: true,
});

// 3. Poll for completion
const transcript = await pollTranscriptionStatus(jobId);

// 4. Store results
await saveTranscript(recordingId, transcript);

Audio Playback

See references/audio-playback.md for wavesurfer.js patterns.

Key Features

• Waveform visualization
• Click-to-seek from transcript
• Playback speed control
• Keyboard shortcuts (space, arrows)

Development

Setup

npm install
cp .env.example .env.local
# Add CASEDEV_API_KEY and DATABASE_URL
npm run db:push
npm run dev

Environment

CASEDEV_API_KEY=sk_case_...       # Case.dev API key
DATABASE_URL=postgresql://...     # PostgreSQL connection
NEXT_PUBLIC_APP_URL=http://localhost:3000

Common Tasks

Adding a New Export Format

1. Create export function in lib/export/
2. Add endpoint in app/api/recordings/[id]/export/
3. Add option to ExportDialog.tsx

Customizing Speaker Labels

// Default labels
const speakerLabels = ['Judge', 'Plaintiff Attorney', 'Defense Attorney', 
                       'Witness', 'Clerk', 'Unknown'];

// In SpeakerEditor component, allow custom labels

Adding Legal Vocabulary

// lib/legal-vocabulary.ts
export const legalVocabulary = [
  'objection', 'sustained', 'overruled', 'plaintiff', 'defendant',
  'voir dire', 'habeas corpus', 'pro bono', 'amicus curiae',
  // Add more terms
];

Export Formats

Format	Use Case
PDF	Official court filing, archive
Word (.docx)	Editing, annotations
Plain Text	Processing, search indexing
SRT	Subtitles for video recordings

Troubleshooting

Issue	Solution
Transcription stuck	Check Case.dev API status, verify audio format
Audio won't play	Verify audio URL accessible, check CORS
Speaker labels wrong	Use SpeakerEditor to reassign
Export fails	Check transcript exists, verify format support
Waveform not showing	Ensure wavesurfer.js loaded, check audio src