ffmpeg-filter-complex-patterns

## CRITICAL GUIDELINES

### Windows File Path Requirements

**MANDATORY: Always Use Backslashes on Windows for File Paths**

When using Edit or Write tools on Windows, you MUST use backslashes (`\`) in file paths, NOT forward slashes (`/`).

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## Quick Reference

| Task | Command Pattern |
|------|-----------------|
| Basic filter_complex | `-filter_complex "[0:v][1:v]overlay"` |
| Named labels | `[input]filter[output]` |
| Chain filters | `filter1,filter2,filter3` |
| Separate chains | `chain1;chain2` |
| Map output | `-map "[label]"` |

## When to Use This Skill

Use for **complex filtergraph operations**:
- Multi-input compositions (PiP, grids, overlays)
- Video transitions and effects
- Audio mixing and routing
- Stream splitting for multiple outputs
- GPU + CPU hybrid processing

**For basic filters**: use `ffmpeg-fundamentals-2025`
**For hardware acceleration**: use `ffmpeg-hardware-acceleration`

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# FFmpeg filter_complex Reference (2025)

Comprehensive guide to complex filtergraphs, multi-input compositions, and advanced filter chains.

## filter_complex Syntax

### Basic Structure

```
-filter_complex "filterchain1;filterchain2;..."
```

Each filterchain consists of:
- **Input labels**: `[input_label]`
- **Filter(s)**: `filter1,filter2,...` (comma-separated)
- **Output labels**: `[output_label]`

### Complete Syntax

```
[input_label1][input_label2]filter=param1=value1:param2=value2[output_label]
```

### Syntax Components

| Component | Description | Example |
|-----------|-------------|---------|
| `[0:v]` | Video stream from input 0 | First input video |
| `[0:a]` | Audio stream from input 0 | First input audio |
| `[1:v]` | Video stream from input 1 | Second input video |
| `[label]` | Custom named label | User-defined |
| `,` | Chain filters sequentially | `scale,fps` |
| `;` | Separate independent chains | `chain1;chain2` |
| `=` | Parameter assignment | `scale=1280:720` |
| `:` | Parameter separator | `w=1280:h=720` |

### Stream References

|