1edid-decode(1) General Commands Manual edid-decode(1)
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6 edid-decode - Decode EDID data in human-readable format
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9 edid-decode <options> [in [out]]
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12 edid-decode decodes EDID monitor description data in human-readable
13 format. If [in] is not given, or [in] is '-', then the EDID will be
14 read from standard input. If [out] is given then the EDID that was read
15 from [in] is written to [out] or to standard output if [out] is '-'. By
16 default the output is written as a hex dump when writing to standard
17 output or a raw EDID if written to a file.
18 If [out] is given then edid-decode only does the conversion, it will
20 skip the decoding step.
21 Input files may be raw binaries or ASCII text. ASCII input is scanned
23 for hex dumps; heuristics are included to search for hexdumps in edid-
24 decode(1) output (as long as the initial hex dump was included),
25 xrandr(1) property output and Xorg(1) log file formats, otherwise the
26 data is treated as a raw hexdump. EDID blocks for connected monitors
27 can be found in /sys/class/drm/*/edid on modern Linux systems with ker‐
28 nel modesetting support.
29 All timings are shown in a short format, for example:
31 VIC 16: 1920x1080 60.000 Hz 16:9 67.500 kHz 148.500 MHz
33 (native)
34 VIC 5: 1920x1080i 60.000 Hz 16:9 33.750 kHz 74.250 MHz
35 VIC 39: 1920x1080i 50.000 Hz 16:9 31.250 kHz 72.000 MHz
36 Each format starts with a timings type prefix, the resolution, an
38 optional interlaced indicator ('i'), the frame rate (field rate for
39 interlaced formats), the picture aspect ratio, the horizontal fre‐
40 quency, the pixelclock frequency and optionally additional flags
41 between parenthesis.
42 Note that for interlaced formats the frame height is given, not the
44 field height. So each field in a 1920x1080i format has 540 lines.
45 Detailed timings have another 2-3 lines of data:
47 VIC 16: 1920x1080 60.000 Hz 16:9 67.500 kHz 148.500 MHz
49 (native)
50 Hfront 88 Hsync 44 Hback 148 Hpol P
51 Vfront 4 Vsync 5 Vback 36 Vpol P
52 VIC 5: 1920x1080i 60.000 Hz 16:9 33.750 kHz 74.250 MHz
53 Hfront 88 Hsync 44 Hback 148 Hpol P
54 Vfront 2 Vsync 5 Vback 15 Vpol P Vfront +0.5
55 Odd Field
56 Vfront 2 Vsync 5 Vback 15 Vpol P Vback +0.5
57 Even Field
58 VIC 39: 1920x1080i 50.000 Hz 16:9 31.250 kHz 72.000 MHz
59 Hfront 32 Hsync 168 Hback 184 Hpol P
60 Vfront 23 Vsync 5 Vback 57 Vpol N Both Fields
61 These describe the horizontal and vertical front porch, sync, backporch
63 and sync polarity values. For interlaced formats there are two lines
64 for the vertical information: one for the Odd Field (aka Field 1) and
65 one for the Even Field (aka Field 2). The vertical front porch of the
66 Odd Field is actually 2.5 (hence the 'Vfront +0.5' at the end of the
67 line), and the back porch of the Even Field is actually 15.5 (hence the
68 'Vback +0.5' at the end of the line).
69 There is a special 'VIC 39' interlaced format where both fields have
71 the same vertical timings, in that case this is marked with 'Both
72 Fields'.
73 The following timing types can be shown:
75 DMT #: Discrete Monitor Timing (see DMT 1.3 standard). The num‐
78 ber is the DMT ID in hexadecimal.
79 CVT: Coordinated Video Timings (formula-based, see CVT 1.2 stan‐
81 dard)
82 GTF: Generalized Timing Formula (formula-based, see GTF 1.1
84 standard)
85 IBM: Old IBM Timings
87 Apple: Old Apple Timings
89 VIC #: Video Identification Code (see CTA-861 standard). The
91 number is the actual
92 VIC code.
93 HDMI VIC #: HDMI-specific Video Identification Code (see HDMI
95 2.1 standard). The number
96 is the actual HDMI VIC code.
97 DTD #: Detailed Timings Descriptor (see EDID standard). Also
99 used for
100 DisplayID Video Timing Modes Types I, II, VI and VII. The
101 number denotes that this is the Nth DTD in the EDID.
102 By default DTDs are shown in the long format while others are just
104 shown in the short format. With the option --short-timings all timings
105 are shown in short format only. With the option --long-timings all tim‐
106 ings are shown in long format.
107 Alternate formats for long timings can be chosen via the --xmodeline or
109 --fbmode options.
110
113 The following EDID standards are supported by edid-decode:
114 EDID 1.3: VESA Enhanced Extended Display Identication Data Stan‐
116 dard, Release A, Revision 1
117 EDID 1.4: VESA Enhanced Extended Display Identication Data Stan‐
119 dard, Release A, Revision 2
120 DisplayID 1.3: VESA Display Identification Data (DisplayID)
122 Standard, Version 1.3
123 DisplayID 2.0: VESA DisplayID Standard, Version 2.0
125 DI-EXT: VESA Display Information Extension Block Standard,
127 Release A
128 LS-EXT: VESA Enhanced EDID Localized String Extension Standard,
130 Release A
131 VTB-EXT: VESA Video Timing Block Extension Data Standard,
133 Release A
134 DTCDB: VESA Display Transfer Characteristics Data Block Stan‐
136 dard, Version 1.0
137 DDDB: VESA Display Device Data Block (DDDB) Standard, Version 1
139 HDMI 1.4b: High-Definition Multimedia Interface, Version 1.4b
141 HDMI 2.1: High-Definition Multimedia Interface, Version 2.1
143 HDMI 2.1: Amendment A1 to HDMI Specification Version 2.1
145 CTA-861-G: A DTV Profile for Uncompressed High Speed Digital
147 Interfaces
148 SPWG Notebook Panel Specification, Version 3.5
150 EPI Embedded Panel Interface, Revision 1.0
152 The following related standards are also used by edid-decode:
155 DMT 1.3: VESA and Industry Standards and Guidelines for Computer
157 Display Monitor Timing (DMT), Version 1.0, Rev. 13
158 CVT 1.2: VESA Coordinated Video Timings (CVT) Standard, Version
160 1.2
161 GTF 1.1: VESA Generalized Timing Formula Standard, Version: 1.1
163
166 -h, --help
167 Prints the help message.
168 -o, --output-format=<fmt>
170 If [out] is specified, then write the EDID in format <fmt>.
171 The output format can be one of:
172 hex: hex numbers in ascii text (default for stdout)
173 raw: binary data (default unless writing to stdout)
174 carray: c-program struct
175 -c, --check
177 Check if the EDID conforms to the standards. Warnings and fail‐
178 ures are reported at the end.
179 -C, --check-inline
181 Check if the EDID conforms to the standards. Warnings and fail‐
182 ures are reported as they happen.
183 -p, --preferred-timing
185 Report the preferred timing at the end.
186 -S, --short-timings
188 Report all video timings in a short format.
189 -L, --long-timings
191 Report all video timings in a long format.
192 -X, --xmodeline
194 Report all long video timings in the ModeLine format as defined
195 in xorg.conf(5). This ModeLine can be used in the xorg.conf
196 file or passed to xrandr(1) with the xrandr --newmode option.
197 -F, --fbmode
199 Report all long video timings in the video mode format as
200 defined in fb.modes(5).
201 -V, --v4l2-timings
203 Report all long video timings in the video mode format as
204 defined in the linux header v4l2-dv-timings.h for use with the
205 V4L2 VIDIOC_S_DV_TIMINGS ioctl.
206 -s, --skip-hex-dump
208 Skip the initial hex dump of the EDID.
209 --skip-sha
211 Don't show the SHA hash. Normally edid-decode will show the SHA,
212 i.e. the hash of the git commit used to compile edid-decode.
213 This uniquely identifies the version of edid-decode that is used
214 to generate the warnings and failures. But it will also change
215 the output of edid-decode for every new commit in the git repos‐
216 itory, even if nothing else changed in the edid-decode output.
217 Use this option to avoid including the SHA in the edid-decode
218 output.
219 -e, --extract
221 Extract the contents of the first block in hex values. This was
222 always done in old edid-decode versions. To get the same behav‐
223 ior add this option.
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227 Not all fields are decoded, or decoded completely. Some fields' decod‐
228 ing may appear to corrupt the output (for example, detailed string sec‐
229 tions have their contents printed literally). edid-decode does attempt
230 to validate its input against the relevant standards, but its opinions
231 have not been double-checked with the relevant standards bodies, so
232 they may be wrong. Do not rely on the output format, as it will likely
233 change in future versions of the tool as additional fields and exten‐
234 sions are added.
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237 Xorg(1), xrandr(1), xorg.conf(5), fb.modes(5)
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240 edid-decode was written by Adam Jackson, with contributions from Eric
241 Anholt, Damien Lespiau, Hans Verkuil and others. For complete history
242 and the latest version, see http://git.linuxtv.org/cgit.cgi/edid-
243 decode.git
244 edid-decode(1)