Feedback: guides-noise_reduction_streaming

Documentation Feedback

Original URL: https://www.assemblyai.com/docs/guides/noise_reduction_streaming
Category: guides
Generated: 05/08/2025, 4:39:28 pm

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Claude Sonnet 4 Feedback

Generated: 05/08/2025, 4:39:27 pm

Technical Documentation Analysis & Feedback

Overall Assessment

This documentation provides a functional code example but lacks the depth and structure needed for production use. Here’s my detailed analysis and recommendations:

🚨 Critical Issues

1. Missing Prerequisites & Setup

Problem: Users may fail at the first step due to unclear requirements.

Recommendations:

## Prerequisites

- Python 3.7 or higher
- A microphone connected to your system
- AssemblyAI account with paid plan (Streaming STT requires upgrade)
- Audio drivers supporting 16kHz sampling rate

## System Requirements

- **Operating System**: Windows 10+, macOS 10.14+, or Linux
- **Memory**: Minimum 2GB RAM (4GB+ recommended for real-time processing)
- **Audio**: Working microphone with system permissions

2. Security & API Key Management

Problem: Hardcoded API key example promotes bad security practices.

Add this section:

## Secure API Key Setup

**⚠️ Never hardcode API keys in your source code**

### Option 1: Environment Variables (Recommended)
```bash
export ASSEMBLYAI_API_KEY="your_api_key_here"

import os
api_key = os.getenv('ASSEMBLYAI_API_KEY')
if not api_key:
    raise ValueError("Please set ASSEMBLYAI_API_KEY environment variable")

Option 2: Configuration File

Create a config.json file (add to .gitignore):

{
    "api_key": "your_api_key_here"
}

## 📚 Missing Information

### 1. **Error Handling & Troubleshooting**
Add comprehensive error handling section:

```markdown
## Error Handling & Troubleshooting

### Common Issues

| Error | Cause | Solution |
|-------|-------|----------|
| `ModuleNotFoundError: No module named 'assemblyai'` | Missing dependencies | Run `pip install -r requirements.txt` |
| `Authentication failed` | Invalid API key | Verify API key in dashboard |
| `Microphone not found` | Audio device issues | Check system audio settings |
| `Memory error during processing` | Insufficient RAM | Reduce buffer_size to `int(sample_rate * 0.25)` |

### Advanced Error Handling

```python
def robust_noise_reduced_mic_stream(sample_rate=16000, max_retries=3):
    retry_count = 0
    while retry_count < max_retries:
        try:
            mic = aai.extras.MicrophoneStream(sample_rate=sample_rate)
            buffer = np.array([], dtype=np.int16)
            buffer_size = int(sample_rate * 0.5)

            for raw_audio in mic:
                try:
                    audio_data = np.frombuffer(raw_audio, dtype=np.int16)
                    buffer = np.append(buffer, audio_data)

                    if len(buffer) >= buffer_size:
                        # Add validation
                        if np.max(np.abs(buffer)) == 0:
                            logging.warning("Silent audio detected, skipping noise reduction")
                            buffer = buffer[-1024:]
                            continue

                        float_audio = buffer.astype(np.float32) / 32768.0
                        denoised = nr.reduce_noise(
                            y=float_audio,
                            sr=sample_rate,
                            prop_decrease=0.75,
                            n_fft=1024,
                        )
                        int_audio = (denoised * 32768.0).astype(np.int16)
                        buffer = buffer[-1024:]
                        yield int_audio.tobytes()

                except Exception as e:
                    logging.error(f"Audio processing error: {e}")
                    continue

        except Exception as e:
            retry_count += 1
            logging.error(f"Stream error (attempt {retry_count}/{max_retries}): {e}")
            if retry_count >= max_retries:
                raise
            time.sleep(1)

2. Configuration Options

Add detailed parameter explanations:

## Configuration Parameters

### Noise Reduction Settings

| Parameter | Default | Description | Recommended Range |
|-----------|---------|-------------|-------------------|
| `prop_decrease` | 0.75 | Proportion of noise to reduce (0-1) | 0.5-0.9 |
| `n_fft` | 1024 | FFT window size | 512, 1024, 2048 |
| `buffer_size` | 0.5 seconds | Processing window | 0.25-1.0 seconds |

### Performance Tuning

**For low-latency applications:**
```python
# Reduce buffer size and processing window
buffer_size = int(sample_rate * 0.25)  # 0.25 seconds
prop_decrease = 0.5  # Less aggressive noise reduction

For high-quality processing:

# Larger buffer for better noise profiling
buffer_size = int(sample_rate * 1.0)  # 1 second
n_fft = 2048  # Higher resolution

## 🛠 Code Improvements

### 1. **Better Code Structure**
Reorganize into a class-based approach:

```python
class NoiseReducedTranscriber:
    def __init__(self, api_key: str, sample_rate: int = 16000,
                 noise_reduction_params: dict = None):
        self.api_key = api_key
        self.sample_rate = sample_rate
        self.noise_params = noise_reduction_params or {
            'prop_decrease': 0.75,
            'n_fft': 1024
        }
        self.client = None
        self._setup_client()

    def _setup_client(self):
        """Initialize the streaming client with event handlers."""
        # Implementation here

    def start_transcription(self):
        """Start the transcription process."""
        # Implementation here

    def stop_transcription(self):
        """Gracefully stop transcription."""
        # Implementation here

2. Add Logging Configuration

import logging
from datetime import datetime

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    handlers=[
        logging.FileHandler(f'transcription_{datetime.now().strftime("%Y%m%d_%H%M%S")}.log'),
        logging.StreamHandler()
    ]
)

📖 Documentation Structure Improvements

Recommended Structure:

# Apply Noise Reduction to Audio for Streaming Speech-to-Text

## Overview
## Use Cases
## Prerequisites
## Installation
## Quick Start
## Configuration
## Step-by-Step Guide
## Advanced Usage
## Performance Optimization
## Troubleshooting
## API Reference
## Examples
## Best Practices
## FAQ

Add Performance Metrics Section:

## Performance Expectations

| Scenario | Latency | CPU Usage | Memory Usage |
|----------|---------|-----------|--------------|
| Standard (16kHz, 0.5s buffer) | ~500ms | 15-25% | ~100MB |
| Low-latency (16kHz, 0.25s buffer) | ~250ms | 20-30% | ~80MB |
| High-quality (16kHz, 1.0s buffer) | ~1000ms | 10-20% | ~150MB |

🎯 User Experience Improvements

1. Add Interactive Examples

## Try It Out

Run this minimal example to test your setup:

```python
# test_setup.py
import assemblyai as aai

def test_microphone():
    """Test if microphone is working"""
    try:
        mic = aai.extras.Microphone

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