EDID Parser

Comprehensive EDID parsing and analysis skill for Linux systems.

Quick Start

1. Parse a single EDID file

# From sysfs (Linux)
edid-decode /sys/class/drm/card0-HDMI-A-1/edid

# Or use our script
python3 scripts/parse_edid.py /sys/class/drm/card0-HDMI-A-1/edid

2. List all display outputs

bash scripts/list_outputs.sh

3. Validate and generate diagnostic report

bash scripts/validate_edid.sh /path/to/edid.bin

4. Extract key information (JSON)

python3 scripts/extract_info.py /path/to/edid.bin

5. Batch process multiple EDID files

python3 scripts/batch_validate.py /path/to/edid/directory/

Features

Feature 1: EDID Validity Check ✅

Validates if EDID is:

• Present and non-empty
• Has valid header (00 FF FF FF FF FF FF 00)
• Has valid checksum
• Can be decoded by edid-decode

Usage:

bash scripts/validate_edid.sh /sys/class/drm/card0-HDMI-A-1/edid

Feature 2: Diagnostic Report

Generates human-readable diagnostic report with:

• Basic information (manufacturer, model, year)
• Display capabilities (resolution, refresh rate, screen size)
• Feature support (audio, YCbCr, HDR, VRR)
• Warnings and issues

Usage:

python3 scripts/diagnostic_report.py /path/to/edid.bin

Feature 3: Human-Readable Report

Converts technical EDID data to easy-to-understand Chinese report.

Usage:

python3 scripts/extract_info.py /path/to/edid.bin

Output example:

📺 Display Info
   Manufacturer: Samsung (SAM)
   Model: FTV
   Production Date: Week 4, 2020
   
🖥️ Display Capabilities
   Max Resolution: 1920x1080 @ 60Hz
   Screen Size: 32 inches
   Audio: Supported (2-channel PCM)
   
🎨 Color Space
   RGB: Supported
   YCbCr 4:4:4: Supported
   YCbCr 4:2:2: Supported

⚠️ Issues/Warnings
   - Only 60Hz supported, no high refresh rate

Feature 4: Batch Processing

Process multiple EDID files and generate summary report.

Usage:

python3 scripts/batch_validate.py ~/Downloads/edid/test-samples/Digital/

Output:

=== Batch EDID Validation ===
Total: 10 | Valid: 9 | Invalid: 1 | Warnings: 3

Invalid:
  - Digital/Sony/MS_0003/F19C835333F6 (128 bytes - Too small)

With Warnings:
  - Digital/Goldstar/GSM0000/A36298C521A5
  - Digital/TCL/TCL0000/0067660D05BD

Scripts

Prerequisites

• edid-decode must be installed:

  sudo apt-get install edid-decode
  

Common EDID File Locations

Linux

# Find all EDID files
find /sys/class/drm -name "edid" -type f

# Typical paths
/sys/class/drm/card0-HDMI-A-1/edid
/sys/class/drm/card0-DP-1/edid
/sys/class/drm/card0-DVI-D-1/edid

Extract from file

# Extract binary from text file
cat EDID.txt | grep -E '^([a-f0-9]{32}|[a-f0-9 ]{47})$' | tr -d '[:space:]' | xxd -r -p > EDID.bin

Examples

Example 1: Check monitor capabilities

User says: "What resolutions and refresh rates does my monitor support?"

Action:

python3 scripts/extract_info.py /path/to/edid.bin
# Or use built-in test sample:
python3 scripts/extract_info.py samples/test_tv_4k.bin

Example 2: Use built-in test samples

The skill includes sample EDID files for testing:

# 4K TV sample (3840x2160 @ 30Hz)
python3 scripts/extract_info.py samples/test_tv_4k.bin

# 1080p Monitor sample (1920x1080 @ 60Hz)  
python3 scripts/extract_info.py samples/test_monitor_1080p.bin

# 4K Streaming stick sample (3840x2160 @ 60Hz)
python3 scripts/extract_info.py samples/test_stick_4k.bin

Example 3: Validate all EDID files in a directory

User says: "Check if all EDID files in this directory have any issues"

Action:

python3 scripts/batch_validate.py ~/Downloads/edid/test-samples/Digital/

Example 4: Debug display issue

User says: "Monitor not displaying, is it an EDID issue?"

Action:

bash scripts/validate_edid.sh /sys/class/drm/card0-HDMI-A-1/edid

Check for:

• Empty EDID (no display connected)
• Invalid checksum (corrupted)
• Missing DTD (no detailed timing)

Troubleshooting

EDID is empty

• Monitor may be in sleep mode or disconnected
• Try waking the monitor
• Check cable connections

EDID decode errors

• EDID may be corrupted
• Monitor may not support standard EDID

No display detected

• Check /sys/class/drm/ for available outputs
• Try different port (HDMI/DP/DVI)

References

• references/manufacturer_codes.md - EDID manufacturer codes
• references/edid_spec.md - EDID specification overview
• references/feature_plan.md - Feature roadmap