EDID Parser

Parse and analyze EDID (Extended Display Identification Data) from monitors and displays. USE WHEN: (1) User wants to read/parse display EDID information; (2...

Security Scan

The skill's code and instructions match its stated purpose (reading/parsing EDID on Linux); it reads local sysfs and EDID files and runs the expected edid-decode tool — no network exfiltration or unrelated credentials requested.

Purpose & Capability

The skill is an EDID parser for Linux and its scripts operate on /sys/class/drm and EDID files, which is appropriate. Minor mismatch: SKILL.md and docs claim support for binary .bin files, but batch_validate.py explicitly skips .bin files when scanning directories (it still can process .bin if given directly to other scripts). This looks like a small implementation inconsistency rather than malicious behavior.

Instruction Scope

Runtime instructions and scripts only read local EDID files and run the local edid-decode binary; they do not make network calls or require secrets. One documentation snippet (references/edid_spec.md) shows 'echo 1 > /sys/class/drm/card0-HDMI-A-1/edid' to force a re-read — that writes to sysfs and requires elevated privileges and can affect kernel/device state. That write operation appears only in a reference doc, not in the primary Quick Start scripts, so treat it as an advisory example rather than an automated action.

Install Mechanism

No install spec is provided and scripts are local files. The only external dependency is the standard edid-decode utility (documented). No downloads, external packages, or unusual installers are used.

Credentials

The skill requests no environment variables or credentials. It accesses system paths under /sys/class/drm and user-supplied file paths, which is proportional to parsing EDID data.

Persistence & Privilege

always is false and the skill does not request persistent system-wide configuration or modify other skills. Scripts operate on files provided or discovered at runtime and do not install background services.

Assessment

This skill appears coherent for parsing EDID on Linux. Before using it: (1) install edid-decode (sudo apt-get install edid-decode); (2) run the scripts locally — they only read files under /sys/class/drm or files you point them to; (3) avoid running commands that write to sysfs (e.g., echo > /sys/class/drm/...) unless you understand the effect and have appropriate privileges; (4) note the minor inconsistency where batch_validate.py skips .bin files when scanning directories (you can still pass .bin files directly to other scripts); (5) inspect scripts if you will run them with elevated privileges. Overall the skill is internally consistent with its stated purpose.

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

Script	Description
list_outputs.sh	List all available display outputs on Linux
parse_edid.sh	Parse and display EDID in detail
extract_info.py	Extract key info as JSON
validate_edid.sh	Validate EDID and check for issues
diagnostic_report.py	Generate human-readable diagnostic report
batch_validate.py	Batch process multiple EDID files

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