Extended Display Identification Data (EDID) is a metadata format for display devices to describe their capabilities to a video source (e.g Monitor/ TV panels). The data format is defined by a standard published by the Video Electronics Standards Association (VESA).
Specific to a dispaly
Stores a list of capabilities for the display
Includes vendor and product information, display parameters, times, preferences, gamma, colorimetry, audio capabilities, extension blocks
EDID is implemented for DVI, HDMI, and DisplayPort. Some very cheap monitors still (for cost saving) do not implement EDID standard (in which case VBT entries for such monitors are required).
2. How to dump EDID in Linux?
Linux i915 graphics driver has capability to do it.
2.1 To Locate
You need to find for which display connector you want to dump EDID.
Manufacturer: RTK Model bc32 Serial Number 16843009 Made week 48 of 2018 EDID version: 1.3 Digital display Image size is variable Gamma: 2.20 DPMS levels: Off Supported color formats: RGB 4:4:4, YCrCb 4:4:4, YCrCb 4:2:2 Default (sRGB) color space is primary color space First detailed timing is preferred timing Established timings supported: 640x480@60Hz 800x600@60Hz 1024x768@60Hz Standard timings supported: 1920x1080@60Hz 1600x900@60Hz 1360x765@60Hz 1280x720@60Hz 1024x576@60Hz 960x540@60Hz 848x477@60Hz 720x405@60Hz Detailed mode: Clock 148.500 MHz, 344 mm x 195 mm 1920 2008 2052 2200 hborder 0 1080 1082 1087 1125 vborder 0 +hsync +vsync Monitor name: RTK Serial number: demoset-1 Monitor ranges (bare limits): 50-65Hz V, 34-84kHz H, max dotclock 190MHz Has 1 extension blocks Checksum: 0x26 (valid)
CEA extension block Extension version: 3 39 bytes of CEA data Video data block VIC 3 720x480@60Hz VIC 62 1280x720@30Hz VIC 19 1280x720@50Hz VIC 4 1280x720@60Hz VIC 15 1440x480@60Hz VIC 34 1920x1080@30Hz VIC 31 1920x1080@50Hz VIC 16 1920x1080@60Hz Extended tag: video capability data block YCbCr quantization: Selectable (via AVI YQ) (1) RGB quantization: Selectable (via AVI Q) (1) PT scan behaviour: Always Overscannned (1) IT scan behaviour: Always Overscannned (1) CE scan behaviour: Always Overscannned (1) Extended tag: Colorimetry data block xvYCC601 xvYCC709 sYCC601 AdobeYCC601 AdobeRGB BT2020cYCC BT2020YCC BT2020RGB Audio data block Linear PCM, max channels 2 Supported sample rates (kHz): 192 176.4 96 88.2 48 44.1 32 Supported sample sizes (bits): 24 20 16 Speaker allocation data block Speaker map: FL/FR Vendor-specific data block, OUI 000c03 (HDMI) Source physical address 1.0.0.0 DC_36bit DC_30bit DC_Y444 Maximum TMDS clock: 300MHz Extended tag: HDR static metadata data block Electro optical transfer functions: Traditional gamma - SDR luminance range Traditional gamma - HDR luminance range SMPTE ST2084 Supported static metadata descriptors: Static metadata type 1 Desired content max luminance: 105 Desired content max frame-average luminance: 105 Desired content min luminance: 79 Underscans PC formats by default Basic audio support Supports YCbCr 4:4:4 Supports YCbCr 4:2:2 2 native detailed modes Detailed mode: Clock 108.000 MHz, 344 mm x 195 mm 1600 1624 1704 1800 hborder 0 900 901 904 1000 vborder 0 +hsync +vsync Detailed mode: Clock 85.500 MHz, 344 mm x 195 mm 1366 1436 1579 1792 hborder 0 768 771 774 798 vborder 0 +hsync +vsync Detailed mode: Clock 74.250 MHz, 344 mm x 195 mm 1280 1390 1430 1650 hborder 0 720 725 730 750 vborder 0 +hsync +vsync Checksum: 0x4 (valid)
EDID block does NOT conform to EDID 1.3! Detailed block string not properly terminated EDID block does not conform at all! Detailed blocks filled with garbage Range descriptor contains garbage