# Preset: 1080P HEVC NVENC

File: `hevc_nvenc_1080p.json` — HandBrake preset for GPU-accelerated HEVC (H.265)
compression of 1080p video using NVIDIA NVENC.

## What it does

- **Encoder**: `nvenc_h265` (HEVC on the GPU, not CPU x265)
- **Preset**: `slow` — best quality/speed balance on Pascal-class GPUs;
  `slowest` gains almost nothing but nearly halves the speed
- **Rate control**: VBR, 1850 kbps video (multipass) + 160 kbps AAC stereo audio
- **Resolution**: unchanged up to 1920×1080 (larger sources are downscaled to fit,
  aspect ratio preserved, no upscaling)
- **Framerate**: same as source (VFR passthrough)
- **Container**: MP4, web-optimized, chapters + metadata preserved
- **Subtitles**: not included

Tuned so a ~3 hour 1080p source lands around **2.5–2.7 GiB**. Reference result:
8.06 GB h264 1080p source (2h59m) → 2.68 GiB HEVC, ~26 min encode on a GTX 1060
(~220 fps average).

## Requirements

- HandBrake 1.8+ (`HandBrakeCLI.exe` for command line use)
- NVIDIA GPU with HEVC NVENC support (GTX 10-series or newer) and recent drivers

## Usage — command line

```bash
HandBrakeCLI --preset-import-file hevc_nvenc_1080p.json \
  -Z "1080P HEVC NVENC" \
  -i input.mp4 -o output.mp4
```

Windows example:

```powershell
& "C:\Program Files\HandBrake\HandBrakeCLI.exe" `
  --preset-import-file hevc_nvenc_1080p.json `
  -Z "1080P HEVC NVENC" `
  -i "F:\Media\input.mp4" -o "F:\Media\output.mp4"
```

## Usage — HandBrake GUI

1. Open HandBrake → **Presets** panel → **Import** (bottom of the panel).
2. Select `hevc_nvenc_1080p.json`.
3. Open your source, choose the **1080P HEVC NVENC** preset, set the output path, Start.

## Adjusting the target size

The output size is driven by `VideoAvgBitrate` (kbps) and the video duration:

```
VideoAvgBitrate ≈ (target_bytes × 8 / 1000 − audio_kbps × duration_s) / duration_s
```

For a 2.5 GiB target with 160 kbps audio, that simplifies to roughly:

```
VideoAvgBitrate ≈ 21500000 / duration_seconds − 160
```

| Duration | VideoAvgBitrate | Approx. output |
|----------|-----------------|----------------|
| 1 h      | ~5800 kbps      | ~2.5 GiB       |
| 1.5 h    | ~3800 kbps      | ~2.5 GiB       |
| 2 h      | ~2800 kbps      | ~2.5 GiB       |
| 3 h      | 1850 kbps (current) | ~2.6 GiB   |
| 4 h      | ~1330 kbps      | ~2.5 GiB       |

Raise the value for better quality (larger file), lower it for a smaller file.
For 1080p HEVC, going below ~1200 kbps starts to show visible artifacts.