ByeBye Bytes

Drop a video. Get a smaller one. A native macOS app that shrinks videos to H.265/MP4 using Apple Silicon's hardware media engine — with zero settings to tinker with.

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What it does

Drag one or more videos onto the window. ByeBye Bytes inspects each file, picks the smartest encode plan, and writes a smaller H.265 MP4 to your output folder. That's it.

• One video dropped → a hardware-encoded HEVC copy.
• Two or more dropped → choose Encode each (batch) or Merge into one (concatenate, letterboxed if resolutions differ).
• Already well-compressed → the app quietly skips the encode and leaves your original untouched.

No settings menus, no bitrate sliders, no preset wizard. The app figures it out.

Why

Most video compressors force you to make a dozen decisions before they'll touch a file. ByeBye Bytes takes the opposite approach: it knows what "visually lossless HEVC" looks like for each source and just produces it. If the source is already HEVC at a reasonable bitrate, it remuxes — no re-encode, no quality loss, instant.

Features

• Hardware HEVC via VideoToolbox on Apple Silicon (M-series media engine).
• Auto-quality — inspects resolution, bit depth, HDR metadata, source bitrate, and derives an EncodeRecipe per file.
• HDR passthrough — preserves HDR10/HLG colour metadata end-to-end.
• 8-bit → HEVC Main, 10-bit → HEVC Main10 — picked automatically.
• Fast-path remux for sources already HEVC at a sensible bitrate (no re-encode, same quality, instant).
• Merge mode — combines N clips into one file. Uses AVMutableComposition fast-path when parameters match; falls back to a CoreImage-based normalise + letterbox pipeline when they don't.
• Skip-if-no-gain — if the encoded output isn't meaningfully smaller (< 2% saving), the app discards it and tells you the original is already well-compressed.
• ADHD-friendly UI — one focal point at a time, determinate progress bars only, no modals, respects accessibilityReduceMotion.
• Liquid Glass icon + UI surfaces on macOS 26 Tahoe (dark / tinted / clear variants auto-derived), with material fallbacks on macOS 14–15.
• Keyboard — ⌘O opens the file picker from any state.

Requirements

• macOS 14 Sonoma or later (Liquid Glass appearance variants require macOS 26 Tahoe)
• Apple Silicon (Intel also works — software HEVC encode, slower)

Install

Homebrew (recommended)

brew install --cask saiftheboss7/byebye-bytes/byebye-bytes
xattr -dr com.apple.quarantine "/Applications/ByeBye Bytes.app"

The second command clears macOS's quarantine attribute on the ad-hoc-signed app so Gatekeeper doesn't block it on first launch. You can skip this step by installing with --no-quarantine instead:

brew install --cask --no-quarantine saiftheboss7/byebye-bytes/byebye-bytes

Upgrades land the same way — brew upgrade --cask byebye-bytes (re-run the xattr command after each upgrade, or keep using --no-quarantine). Uninstall with --zap to also remove stored preferences:

brew uninstall --zap --cask byebye-bytes

Tap source: saiftheboss7/homebrew-byebye-bytes.

Prebuilt (no Homebrew)

Download the latest .app from Releases, unzip, and drag ByeBye Bytes.app into /Applications. Because builds are ad-hoc signed, clear quarantine after copying:

xattr -dr com.apple.quarantine "/Applications/ByeBye Bytes.app"

Or right-click the app in Finder → Open once to allow it through Gatekeeper.

Build from source

git clone https://github.com/saiftheboss7/ByeBye-Bytes.git
cd "ByeBye-Bytes"

# Produces build/ByeBye Bytes.app
./build-app.sh

# Install to /Applications
cp -R "build/ByeBye Bytes.app" /Applications/

Requires:

• Swift 5.9+ (ships with Xcode 15+ or the Command Line Tools)
• macOS 14+ as the build host

Optional — to enable full Tahoe Liquid Glass icon variants (compiled via actool), run the Xcode one-time setup:

sudo xcodebuild -license accept
sudo xcodebuild -runFirstLaunch

Then rebuild. Without this, the app ships a flat .icns (still looks great — just no auto-derived dark/tinted/clear variants).

Xcode IDE

Open Package.swift in Xcode, or generate a full Xcode project:

brew install xcodegen
xcodegen generate
open ByeByeBytes.xcodeproj

The generated .xcodeproj is gitignored — project.yml is the source of truth.

How it works

UI (SwiftUI)
  ↓ drop / click / ⌘O
JobQueue (actor-gated, max 2 concurrent encodes)
  ↓
MediaInspector  →  SourceProfile  (AVAsset → resolution, fps, codec,
                                    bit depth, HDR flags, audio info)
  ↓
SettingsResolver  →  EncodeRecipe  (pure function: profile → plan)
  ↓
Encoder
  ├─ RemuxEncoder       (source already HEVC → stream copy into MP4)
  ├─ SingleFileEncoder  (AVAssetReader → AVAssetWriter HEVC re-encode)
  └─ MergeEncoder
       ├─ fast path (AVMutableComposition, no re-encode)
       └─ normalise path (CoreImage letterbox + reader/writer concat)
  ↓
OutputRouter  →  ~/Downloads/<name>.hevc.mp4   (collision-safe: -1, -2, …)

Auto-quality rules

Source trait	Decision
Already HEVC at reasonable bitrate for its resolution	Remux — stream copy, no re-encode
H.264 source	HEVC encode, bitrate cap ≈ 55% of source
HEVC source outside the "sensible" bitrate band	HEVC encode, cap ≈ 85% of source
10-bit or HDR source	HEVC Main10, HDR metadata preserved
Otherwise	HEVC Main
Quality target	AVVideoQualityKey = 0.70 (visually-lossless zone)
GOP	fps × 2 (2-second keyframe interval)
Container tag	hvc1 (Apple/QuickTime-friendly)
Audio	AAC passthrough when possible; else AAC-LC 192 kbps, up to 5.1 channels

"Sensible HEVC bitrate" bands per resolution

Tier	Range
≤ 720p	1.5 – 8 Mbps
≤ 1080p	3 – 15 Mbps
≤ 1440p	5 – 25 Mbps
4K+	10 – 60 Mbps

Project layout

ByeBye Bytes/
├── Sources/ByeByeBytes/
│   ├── App/               # @main entry point
│   ├── Core/              # Types, MediaInspector, SettingsResolver, AppSettings
│   ├── Encoders/          # RemuxEncoder, SingleFileEncoder, MergeEncoder, EncoderCommon
│   ├── Queue/             # JobQueue, OutputRouter, ProgressReporter
│   └── UI/                # SwiftUI views + GlassStyle helpers
├── Resources/
│   ├── AppIcon.icns       # Flat icon (fallback)
│   └── Assets.xcassets/
│       └── AppIcon.icon/  # Liquid Glass layered source (Tahoe)
├── Scripts/
│   └── generate-icon.swift  # Regenerate icon artefacts
├── Package.swift          # SPM manifest
├── project.yml            # xcodegen source of truth
├── App.Info.plist         # Bundle Info.plist
├── ByeByeBytes.entitlements
└── build-app.sh           # SPM → signed .app bundle

Development

# Fast iterative build
swift build
swift run ByeByeBytes

# Full .app bundle (signed, with icon)
./build-app.sh
open "build/ByeBye Bytes.app"

# Regenerate the app icon from source
swift Scripts/generate-icon.swift

Swift 5 language mode is in use — Swift 6 strict-concurrency warnings on AVFoundation types are non-blocking and tracked for a future migration pass.

Contributing

PRs welcome. Please keep changes focused — one logical improvement per PR — and match the existing style (SwiftUI-idiomatic, minimal comments, no speculative abstractions).

License

MIT © 2026 Saif Hassan