01 / CAPTURE
Rooted webOS LG TV
PicCap captures the screen and sends the frames to HyperHDR.
A high resolution
low latency rgbw
ambilight project
PROJECT OVERVIEW
A 12 V individually addressable RGBW build using a rooted 48-inch LG C1 and a Gledopto GL-C-618WL. Select your TV size below to calculate the hardware.
Estimated total cost: around US$150, excluding taxes.
Built around AliExpress components and readily available parts.
02 / LIGHT OUTPUT
Gledopto controller
Receives LED color data from HyperHDR and drives the LED strips.
01
Root the TV
Check root compatibility before buying hardware or planning the build.
Warranty & device risk
Rooting may void warranty. Please understand the risks before rooting.
Can your TV be rooted?
Check your exact LG TV model and installed firmware. Compatibility depends on the software version, not just the screen size.
Check root compatibility ↗Automatic root tool
Open the tool and read its current instructions, supported versions and warnings. Use it only if your TV and firmware meet its requirements.
Open Get Root ↗Confirm screen capture
Install PicCap and HyperHDR from the Homebrew Channel. Start both services and check that PicCap sends frames to HyperHDR. On the LG C1, enabling NV12 in PicCap may be needed.
From a browser on the same network, open http://<your-tv-ip>:8090/ and check the HyperHDR live preview. Confirm that it shows what is playing on the TV. Further setup and calibration can wait.
DRM-protected video in built-in TV apps, such as Netflix, cannot be captured by PicCap on newer TVs. HDMI sources avoid this built-in-app restriction: play your content from a PC or streaming stick connected to the TV.
PicCap capture support ↗Already rooted? Confirm root access and continue. If no supported method is available, stop here: this on-TV capture build requires root. Root access alone does not guarantee PicCap capture compatibility.
Next: choose TV size02
TV & LED layout
Start with the diagonal. Confirm the mounting path before cutting.
0 cm5 cm · Suggested start12 cm
Distance from the TV edge to the centre of the LED strip. Start at 5 cm. Test the glow before fixing the strips.
One setting for strip length, LED count, frame and PDF.
Layout follows the selected TV dimensions and LED inset above. Counts are rounded down to whole LEDs. Confirm connector clearances before cutting.
LED layout
48″
FRONT VIEWLG C1 REFERENCESegments
Select a segment to isolate its LEDs.
All four segments selected.
Estimated cut layout
Total LEDs
Installed strip
Purchase length
Estimated screen sizewidth × height, excluding bezel
03
Power supply & voltage drop
12 V RGBW, individually addressable. Estimates follow the TV size, LED inset and strip rating selected for your build.
Calculation assumptions
Pure copper at 20°C. Both positive and return conductors are included. All four branches are modelled at the longest entered length: a conservative wire estimate. The controller allowance is a planning assumption.
Wire resistance: 20 AWG = 0.0333 Ω/m; 18 AWG = 0.02095 Ω/m; 16 AWG = 0.01317 Ω/m. Real drop can be higher with heat, contacts, fuse holders, adapter leads and the LED strip itself; those are not modelled here.
Wire budget: no more than 3% (0.36 V), reserving 2% (0.24 V) for unmodelled losses within a 5% total-drop target. Measure at the last LED under load: aim for at least 11.4 V from a measured 12.0 V supply. These are design targets, not published failure thresholds.
LED load
Minimum supply rating
Suggested supply size
Recommended brand: BTF-LIGHTING. Choose the 12 V variant with sufficient current capacity.
Worst wire drop
Branch fuse sizing
Planning rule: branch current ÷ 0.75, rounded up to the next MINI blade rating in this guide (2–30 A). One fuse per positive branch, near the distributor. Supply headroom is not added again.
Candidates require verification against the selected fuse datasheet, ambient temperature, inrush and time–current curve, and the ratings of every wire, clip and holder. A fuse does not open instantly at its printed rating. This calculation does not certify protection of the weakest component. Fuse selection reference ↗
| Segment | Load | Current | Wire drop* | Fuse candidate |
|---|
*Includes the common 16 AWG supply-wire drop. Estimated at rated load, not typical movie brightness.
How these numbers are calculated
LED load = installed metres × W/m. Current = power ÷ 12 V. Wire drop = current × resistance × round-trip wire length. Wire heating loss = current² × resistance. The supply includes LEDs, the controller allowance and estimated wire losses, then adds headroom.
Buying more spare strip does not increase the load: only the installed length is powered. A higher-current supply does not fix a long, thin wire; shorten the route, use thicker conductors or redesign the fused power feeds.
BTF strip specification04
Hardware checklist
Select the connection method and rear profile. Calculated parts follow these settings.
TV rear profile
Frame calculator
MOUNTING GEOMETRYInset is measured to the LED centreline. These are planning dimensions, not cut lengths. Allow for rail width, corner joints and connectors; measure the assembled frame before cutting strips. Keep vents clear and support the frame on the stronger lower housing.
3D frame supportsConfigure once · download the complete set
One calculator for the connectors and their supports. All dimensions are in millimetres.
1 Your cable trunking
0° faces the wall; 45° points farther outward. The connector remains open above the LEDs.
2 Where will the supports sit?
Measure from the bottom edge of the TV to the start of the flat lower housing, in a straight line. Include the border and the whole curved transition. No curve measurements needed.
Fine adjustments
3 Your complete set
Drag to rotate. Preview and download use the same settings.
The ZIP contains the required connectors, any separate spacers and assembly dimensions. Print the quantities in the filenames. For a raised back, upper and lower pieces always export together. Print a fit test first.
Build progress
Only the selected method is counted and exported. Ticks for the other method are retained. Items whose calculated specification changes need checking again.
Next: build the four branches05
Wiring schematics
Assemble with power disconnected. Follow one branch at a time.
DC POWER
Correct polarity at the controller INPUT + / − terminals. Use a matching 5.5 × 2.1 mm adapter; never apply 12 V to USB-C or DIN.
Gledopto GL-C-618WLOUTPUT V+ and GND · 16 AWG common wiring
Dots mark connections; line crossings without a dot are not connected. Positive and GND are separate networks. All ports inside one WAGO are connected: never mix +12 V and GND.
Gledopto data outputsWhite 20 AWG · separate DIN for each segment
Leave DOUT at the end of each segment unconnected. IO13 is unused. Labels below are a front-view mapping: check directions carefully when working behind the TV.
- Check the strip direction. LED data travels in one direction only, shown by the arrows on the strip. Connect the controller data wire to DIN (data input), not DOUT. It is possible to connect a strip backwards; confirm its direction before cutting, mounting or wiring. Follow the +12 V and GND labels separately.
- Measure, count and double-check. Measure each side, count its LEDs and allow room for corner gaps and connectors. If using a frame, check the strips against the assembled frame before cutting. Confirm the planned LED counts, cut marks and DIN direction on every segment.
- Cut the strips. Disconnect power and cut only at the marked cut lines. Preserve the connection pads and label each segment.
- Build the positive branches. From the positive distributor, use one MINI fuse holder per segment, then one WAGO 221-412 to join its lead to the branch wire.
- Build the returns and data paths. Run a separate GND wire to each segment and the labelled GPIO signal to that segment’s DIN. Keep data and its GND together along the full route, even without a sleeve. A 4 mm PET sleeve expanding to 5 mm can bundle all three wires; verify the insulated bundle fits.
- Insulate and label. Secure cables without pulling on contacts, leave TV ventilation clear and keep the enclosed mains adapter outside the project enclosure.
06
Software setup
Get capture working first. Then connect the controller and map the outputs.
- Check capture compatibility.
With root access confirmed in step 1, check PicCap support for your exact firmware and capture sources before installation.
PicCap documentation - Install PicCap and HyperHDR on the TV.
Use the current project instructions. Open HyperHDR and confirm its live preview matches the picture. NV12 was needed on the reference LG C1; test your own capture format with SDR and HDR sources.
HyperHDR project - Flash HyperK to the Gledopto.
Disconnect the LED supply and use a USB data cable. Choose the profile matching the actual GL-C-618WL revision. This replaces the factory WLED firmware. Use a Web Serial browser such as Chrome or Edge for flashing; Firefox can view this guide but cannot use the web installer.
Open the HyperK installer - Connect the TV and controller to the router.
Use two LAN ports. Find the controller’s address in the router, then open its interface. Configure the Ethernet-capable board profile; follow HyperK’s initial setup instructions if network access is not yet available.
HyperK setup guide - Configure the LEDs and connect HyperHDR.
Select SK6812 RGBW, set the four outputs from the table and check I2S operation for synchronized segments. In HyperHDR, select the HyperK output driver, enter the controller address and match the total. Save, then adjust inversion only as needed during testing.
Output Edge LED count DIN / direction
07
Hardware testing
Complete these checks before attaching the strips to the TV.
Polarity & continuity
Check +12 V, GND and DIN labels. Inspect insulation and check for shorts. Confirm the fuse and connector ratings for each branch.
One segment at a time
Start with a single segment. Check red, green, blue and white, then repeat for all four outputs. Fix swapped colors or direction before increasing brightness.
Voltage & temperature
Increase brightness gradually within the verified current limits. Measure at the supply, strip input and far end under load. Check wires, contacts and the controller for excessive heat, flicker or resets.
If voltage is low, shorten or thicken the feed, or redesign fused power injection. Do not compensate by raising the supply above the strip’s specified voltage. A calculator pass does not replace these measurements.
After stable bench tests: mount the strips, secure the wiring, test your usual SDR/HDR content, set smoothing to taste, and verify startup and shutdown.