GVF · Ultimate Video Enhancer

HUD Reference

Complete documentation for all four overlay panels — Main, Grading, Settings and Scopes — with controls, shortcuts, and parameter ranges.

Main HUD H

Grading HUD G

Settings HUD I

Scopes HUD S

What is this?

GVF — Ultimate Video Enhancer

A Tampermonkey / Greasemonkey userscript that intercepts every HTML5 <video> element on any website and applies real-time visual post-processing — no browser extension, no server, no installation beyond the script itself. Works on YouTube, Twitch, Netflix, Disney+, Crunchyroll, and any other site that uses a standard HTML5 video player.

⚙

How it works

GVF wraps each video in a processing pipeline and renders the enhanced output as a transparent overlay sitting directly on top of the original player. The video itself is never modified — all effects are applied in real time as each frame is drawn. The pipeline switches automatically between two modes: WebGL2 (GPU) for full GLSL shader support, and SVG filters as a universal fallback.

◈

Render Pipeline

In GPU mode, a WebGL2 Ping-Pong FBO chain processes all active GLSL filters on a single context — each filter reads from the previous FBO and writes to the next. Frame timing uses requestVideoFrameCallback (rVFC) where available, with a requestAnimationFrame fallback. GLSL render rate is configurable: 24 fps (Light), 30 fps (Normal), or 60 fps (Turbo).

⬡

Four Custom Filter Types

WebGL / GLSL Shaders Canvas 2D Overlays SVG Filters Web Audio Filters

Users can write and install custom filters in any of these four types via the built-in code editor. Filters can be shared via the associated PHP website and installed with one click.

◉

Profiles & LUTs

All settings are saved in named User Profiles that can be switched with a single key press. Profiles store every slider value, active filters, render mode, and LUT selection. 3D LUT support accepts tiled PNG and .cube files — fitted to a 4×5 matrix via least-squares regression for zero-overhead GPU application.

⚠

DRM & Browser Compatibility

GVF auto-detects Widevine-protected content via the encrypted event and video.mediaKeys. On DRM streams, WebGL canvas readback is blocked — the script falls back gracefully to SVG mode. On Edge + Widevine L1 with hardware compositing, all GPU filters are silently disabled to prevent black screens.

Chrome Firefox Edge Safari (limited)

↓

Installation

Install Tampermonkey (Chrome / Edge) or Greasemonkey (Firefox), then install the script from Greasy Fork. The script matches *://*/* — it activates on every page automatically and attaches to any <video> element it finds, including those added dynamically after page load via MutationObserver.

Greasy Fork →

Main HUD H

Top-level controls for look presets and the six primary image-science sliders. Always visible when the HUD is shown. Positioned top-left of the video.

Live Preview

User

GPU

+1.00

+0.50

−1.20

+0.20

0.00

HDR

0.00

Width: auto · Position: top-left of video

Preset Buttons

Button	Function
B	Base — enable/disable all GVF processing
D	Dark Moody — cinematic low-key look
O	Teal & Orange — Hollywood color contrast
V	Vibrant Saturation — boosted chroma
P	HDR push — lifts highlights & tone
A	Auto — AI white-balance correction

Render Badge

Shows active render pipeline next to the profile name. GPU = WebGL2 · SVG = SVG filter stack. Switch via the Settings HUD.

Sliders — Primary Image Science

Param	Range	Description
SL	−2 … +2	Shadow Lift — raises or lowers dark tones; controls black-point lift and shadow separation.
SR	−2 … +2	Shadow Roll — shapes the shadow-to-midtone transition curve; affects film-like roll-off.
BL	−2 … +2	Black Level — crushes or opens the absolute black point; use negatively for deep blacks.
WL	−2 … +2	White Level — clips or extends the white ceiling; controls highlight roll-off on bright areas.
DN	−1.5 … +1.5	Depth / Denoise — edge-aware smoothing or depth enhancement. Firefox: disabled
HDR	−1 … +2	HDR tone-mapping strength — tonemap operator applied to the full frame. 0 = bypass.

All six sliders snap to 0 within half a step — makes it easy to return to neutral without typing a value.

Grading HUD G

Fine-grained color grading with 11 tonal controls, per-channel RGB gain (0–255), color-blind simulation, LUT profile selector, and the custom filter manager.

Live Preview

Grading (G) & RGB Gain (0–255)

Contrast

0.0

Black Level

0.0

White Level

0.0

Highlights

0.0

Shadows

0.0

Saturation

0.0

Vibrance

0.0

Sharpen

0.0

Gamma

0.0

Grain (Banding)

0.0

Hue Correction

0.0

R Gain (0-255)

128

G Gain (0-255)

128

B Gain (0-255)

128

Color Blind

None

LUT

None

SVG/WebGL Codes

⬡ Manage

0/0

Width: 340px · Scrollable · Position: below Main HUD

Tonal Controls — range −10 … +10

Control	Description
Contrast	S-curve contrast around midtone pivot
Black Level	Absolute black crush / lift
White Level	White ceiling / clip point
Highlights	Selective highlight roll-off
Shadows	Selective shadow detail recovery
Saturation	Global chroma multiplier
Vibrance	Skin-safe smart saturation
Sharpen	Luma-masked edge sharpening (LumaSharpen)
Gamma	Mid-grey gamma power curve
Grain (Banding)	Film grain / dithering to break banding
Hue Correction	Global hue rotation in HSL space

RGB Gain Channels

Three independent per-channel multipliers, range 0–255, neutral at 128. Applied after all tonal grading. Accent-color tracks the channel color in the slider.

Color Blind Filter

None Protanopia Deuteranopia Tritanomaly

SVG feColorMatrix simulation. Applied on top of all grading — useful for accessibility testing.

LUT Profile + SVG/WebGL Codes

Select a loaded 3D LUT (PNG tiled or .cube), grouped by category. The + button opens the LUT Manager. Below that, SVG/WebGL Codes opens the custom filter code manager — showing active/total count. Disabled in Firefox

Settings HUD I

Export/import all settings as JSON, with screenshot and video recording capture, profile management, GLSL render-mode control, and debug tools.

Live Preview

Settings (I) Export/Import JSON

{
  "enabled": true,
  "darkMoody": true,
  "sl": 1.0,
  "sr": 0.5,
  "bl": -1.2,
  "profile": "user",
  "renderMode": "gpu"
}

Refresh

Save

Select All

Export .json

Import .json

Reset to defaults

⬇ Load Example

Screenshot

Record

⚙️ Config

🐞 Debug: OFF

Tip: paste JSON here → Save

GLSL Mode:

Normal (30 fps)

Width: 420px · Position: below Grading HUD

JSON Textarea

Shows full settings as formatted JSON. Edits trigger a 450ms auto-save debounce — valid JSON is applied immediately to the active profile without pressing Save. Dirty state tracked with data-dirty.

Button Reference

Button	Action
Refresh	Re-reads current settings into the textarea
Save	Applies textarea JSON to active profile immediately
Select All	Selects all textarea text for quick copy
Export .json	Downloads timestamped `gvf-settings_YYYY-MM-DD.json`
Import .json	Opens file picker, applies JSON on load
Reset to defaults	Restores all settings to factory defaults
⬇ Load Example	Fetches example profile from GitHub and applies it
Screenshot	Captures current frame with filters baked. Firefox: disabled
Record	Starts/stops MediaRecorder on processed canvas. Firefox: disabled
⚙️ Config	Opens User Profile Manager overlay
🐞 Debug	Toggles verbose console logging + debug dot indicator

GLSL Mode Selector

Light — 24 fps Normal — 30 fps Turbo — 60 fps

Controls the WebGL render loop target FPS. Switching is live — no restart required. Does not affect video playback quality or actual video FPS. Stored as gvf_glsl_mode.

Scopes HUD S

Live video analysis: 16-bucket luma histogram, per-channel RGB histograms, average saturation meter, and a Y/RGB/Sat footer summary. Updates every ~100 ms via a 160×90 canvas sample.

Live Preview

Scopes (S) live

Luma Y

RGB

Sat

0.34

Y: 0.42

RGB: 0.40

Sat: 0.34

Width: 280px · pointer-events: none · Position: top-left

Sections

Section	Description
Luma Y	16-bucket brightness histogram sampled from the processed frame. Bars: `#4CAF50`, height 40px. Updates with 0.1s CSS transition.
RGB	Three side-by-side 16-bucket histograms for R, G and B channels individually. Height 32px each. Color: R #ff5252 · G #52ff52 · B #5252ff
Sat	Average saturation bar with `linear-gradient(#ffd700 → #ff8c00)`. 0 = fully desaturated, 1 = maximum.
Avg footer	Three read-only cells: average luma Y, average RGB brightness, and average saturation — formatted to 2 decimal places.

Sampling Architecture

A hidden 160×90 canvas is drawn from the primary video element and read back via getImageData(). The loop runs in a requestAnimationFrame at 10 fps (100ms interval). DRM-protected content causes a SecurityError on readback — scopes silently skip that frame.

Scopes are read-only — pointer-events: none. Clicking through to the video works normally even when Scopes is open.

Custom Filter Codes Modal

Full-featured manager for writing, enabling, reordering and hotkey-assigning custom SVG, GLSL, Canvas 2D and Audio filters. Opened via ⬡ Manage in the Grading HUD. Disabled in Firefox

Modal Preview

⬡ Custom Filter Codes (SVG / WebGL)

📚 Library

🔍 Search label, tags, category…

All

GLSL

SVG

🎙

SVG GLSL Canvas Audio

⠿

Cinematic Grade GLSL lut

⌨

✏

🗑

⠿

Vignette Overlay SVG

⌨ Q

✏

🗑

➕ Add new Custom Filter

Label (e.g. "Sobel Sketch")

⬡ WebGL/GLSL

void mainImage(out vec4 O, vec2 U) {
  O = texture(u_video, U/u_res);
}

Width: 560px · Draggable · Centered

Features

Feature	Description
Search	Full-text search across label, tags, category and description
Type filter pills	Filter list to All / GLSL / 2D / SVG / Audio
Type toggles	Global enable/disable per type — snapshots previously enabled filters so re-enabling restores them exactly
Tag cloud	Clickable tag pills appear dynamically from all loaded filter metadata
Drag to reorder	⠿ handle — drag rows to set filter execution order in the pipeline
Hotkey ⌨	Assign any key to toggle a filter on/off. Hotkey badge shown inline on the row
Edit ✏	Opens inline editor: label, filter type dropdown, code textarea, tags, category, description, blend mode
Delete 🗑	Removes filter permanently from storage
📚 Library	Opens `svg.ts3x.cc` — the associated filter-sharing website for one-click installs
DRM banner	Red warning shown when the current domain is on the GLSL blacklist — GLSL rows are dimmed and disabled

Filter Types

GLSL — WebGL2 shader, GLSL ES 3.0 Canvas 2D — rAF loop, ctx API SVG — feColorMatrix / feTurbulence etc. Audio — Web Audio API + Speech

Filters are stored as JSON in GM storage (gvf_custom_svg_codes). Each entry carries: id, label, code, type, enabled, tags, category, description, blendMode, hotkey.

LUT Profile Manager

Upload, organize and apply 3D LUT files (tiled PNG or .cube). Groups with favorites support. Opened via the + button in the Grading HUD LUT row.

Modal Preview

🎨 LUT Profile Manager

🟠 Active LUT: Cinematic Warm

Group

All groups ▾

Add Group

Rename

Delete

⭐ Cinematic Warm

Active

✏

🗑

Cool Shadows

Apply

✏

🗑

📤 Upload PNG LUT

📤 Upload .cube

📦 Export ZIP

📥 Import ZIP

Width: 820px · Draggable · Centered

Features

Feature	Description
Active LUT bar	Always shows the currently applied LUT name at the top
Groups	Organize profiles into named groups. Add / Rename / Delete. Special pseudo-group: ⭐ My Favorites
Group filter	Dropdown filters the profile list to a single group, Favorites, Ungrouped, or All
Apply	Sets the clicked profile as the active LUT — immediately applies to the video pipeline
Upload PNG LUT	Accepts tiled PNG LUT (e.g. 512×512 = 64³). Fitted to a 4×5 affine matrix via least-squares
Upload .cube	Parses standard Resolve/Nuke CUBE files. Supports `DOMAIN_MIN/MAX` and `LUT_3D_SIZE`
Export ZIP	Downloads all LUT profiles as a ZIP of per-profile JSON files
Import ZIP/JSON	Re-imports a previously exported ZIP or a single profile JSON
Favorites ⭐	Star any profile to add it to the Favorites pseudo-group for fast access

LUT Fitting Algorithm

Both PNG and .cube files are sampled at an N³ grid (default 11³ = 1331 points), fitted to a 4×5 affine RGB matrix via least-squares regression, then stored as the matrix coefficients — no texture sampling at runtime, just a single matrix multiply per pixel.

User Profile Manager

Create, switch, rename, delete and import/export named settings profiles. Each profile stores every slider value, render mode, LUT selection and active filters. Opened via ⚙️ Config in the Settings HUD or cycled with F8.

Modal Preview

👤 User Profile Manager

🔵 Active profile: Cinematic

● Cinematic

Active

✏ Rename

🗑

Default

Switch

✏ Rename

🗑

New profile name…

+ Add

💾 Save current profile

📦 Export profiles (ZIP)

📥 Import profiles (ZIP/JSON)

Width: 820px · Draggable · Centered

Features

Feature	Description
Active profile bar	Always shows the currently loaded profile name with a blue indicator
Switch	Loads all settings from the selected profile immediately — sliders, render mode, LUT, filters
Rename ✏	Inline rename of any profile without switching to it
Delete 🗑	Removes profile permanently. Falls back to Default if active profile is deleted
+ Add	Creates a new profile from the current settings state with the typed name
💾 Save current	Explicitly writes all current slider values into the active profile in GM storage
Export ZIP	Downloads all profiles as a ZIP — one JSON file per profile, timestamped filename
Import ZIP/JSON	Accepts a previously exported ZIP or single profile JSON. Merges into existing profiles
F8 cycle	Cycles to the next profile in order without opening the manager. Shift+F8 cycles backwards

What a profile stores

All HUD slider values Render mode (GPU/SVG) Active LUT profile Look toggles B/D/O/V/P/A Auto strength + lock WB All grading uniforms Color blind filter HUD visibility (not saved) Debug mode (not saved)

Auto-save happens on every slider change — the active profile is kept in sync automatically. The 💾 Save button is for explicit force-saves after manual JSON edits in the IO HUD.

Keyboard Shortcuts

All global hotkeys registered by GVF. Shortcuts use capture: true to intercept before the page.

HUD Visibility

H	Toggle Main HUD
G	Toggle Grading HUD
I	Toggle Settings HUD
S	Toggle Scopes HUD

Look Toggles

B	Toggle Base (enable/disable GVF)
D	Toggle Dark Moody
O	Toggle Teal & Orange
V	Toggle Vibrant Saturation
P	Toggle HDR push
A	Toggle Auto white-balance

System

Ctrl+Alt+S	Toggle Scopes HUD (long)
F8	Cycle to next user profile
Ctrl+Alt+X	Switch render mode GPU ↔ SVG