( Please see this thread: viewtopic.php?f=1&t=22374 )
An example image can be obtained here: http://www.speedyshare.com/gPzgE/image.rgba
Click on the large text "Download image.rgba".
I'm using ImageMagick 6.8.0-7 2012-11-30 Q16 on Ubuntu Linux.
I have a number of .rgba files which I would like to modify, specifically change brightness and contrast. This is what identify tells me about the (original) images:
Here's the output of 'identify -verbose' on the original image.identify image.rgba
image.rgba SGI 64x32 64x32+0+0 8-bit sRGB 256c 4.61KB 0.000u 0:00.000
Code: Select all
Image: image.rgba
Format: SGI (Irix RGB image)
Class: PseudoClass
Geometry: 128x128+0+0
Units: Undefined
Type: Palette
Endianess: Undefined
Colorspace: sRGB
Depth: 8-bit
Channel depth:
red: 8-bit
green: 8-bit
blue: 8-bit
Channel statistics:
Red:
min: 240 (0.941176)
max: 240 (0.941176)
mean: 240 (0.941176)
standard deviation: 0 (0)
kurtosis: 0
skewness: 0
Green:
min: 240 (0.941176)
max: 240 (0.941176)
mean: 240 (0.941176)
standard deviation: 0 (0)
kurtosis: 0
skewness: 0
Blue:
min: 240 (0.941176)
max: 240 (0.941176)
mean: 240 (0.941176)
standard deviation: 0 (0)
kurtosis: 0
skewness: 0
Image statistics:
Overall:
min: 240 (0.941176)
max: 240 (0.941176)
mean: 240 (0.941176)
standard deviation: 0 (0)
kurtosis: 0
skewness: 0
Colors: 1
Histogram:
16384: (240,240,240) #F0F0F0 grey94
Colormap: 256
0: ( 0, 0, 0) #000000 black
1: ( 1, 1, 1) #010101 srgb(1,1,1)
2: ( 2, 2, 2) #020202 srgb(2,2,2)
3: ( 3, 3, 3) #030303 grey1
4: ( 4, 4, 4) #040404 srgb(4,4,4)
5: ( 5, 5, 5) #050505 grey2
6: ( 6, 6, 6) #060606 srgb(6,6,6)
7: ( 7, 7, 7) #070707 srgb(7,7,7)
8: ( 8, 8, 8) #080808 grey3
9: ( 9, 9, 9) #090909 srgb(9,9,9)
10: ( 10, 10, 10) #0A0A0A grey4
11: ( 11, 11, 11) #0B0B0B srgb(11,11,11)
12: ( 12, 12, 12) #0C0C0C srgb(12,12,12)
13: ( 13, 13, 13) #0D0D0D grey5
14: ( 14, 14, 14) #0E0E0E srgb(14,14,14)
15: ( 15, 15, 15) #0F0F0F grey6
16: ( 16, 16, 16) #101010 srgb(16,16,16)
17: ( 17, 17, 17) #111111 srgb(17,17,17)
18: ( 18, 18, 18) #121212 grey7
19: ( 19, 19, 19) #131313 srgb(19,19,19)
20: ( 20, 20, 20) #141414 grey8
21: ( 21, 21, 21) #151515 srgb(21,21,21)
22: ( 22, 22, 22) #161616 srgb(22,22,22)
23: ( 23, 23, 23) #171717 grey9
24: ( 24, 24, 24) #181818 srgb(24,24,24)
25: ( 25, 25, 25) #191919 srgb(25,25,25)
26: ( 26, 26, 26) #1A1A1A grey10
27: ( 27, 27, 27) #1B1B1B srgb(27,27,27)
28: ( 28, 28, 28) #1C1C1C grey11
29: ( 29, 29, 29) #1D1D1D srgb(29,29,29)
30: ( 30, 30, 30) #1E1E1E srgb(30,30,30)
31: ( 31, 31, 31) #1F1F1F grey12
32: ( 32, 32, 32) #202020 srgb(32,32,32)
33: ( 33, 33, 33) #212121 grey13
34: ( 34, 34, 34) #222222 srgb(34,34,34)
35: ( 35, 35, 35) #232323 srgb(35,35,35)
36: ( 36, 36, 36) #242424 grey14
37: ( 37, 37, 37) #252525 srgb(37,37,37)
38: ( 38, 38, 38) #262626 grey15
39: ( 39, 39, 39) #272727 srgb(39,39,39)
40: ( 40, 40, 40) #282828 srgb(40,40,40)
41: ( 41, 41, 41) #292929 grey16
42: ( 42, 42, 42) #2A2A2A srgb(42,42,42)
43: ( 43, 43, 43) #2B2B2B grey17
44: ( 44, 44, 44) #2C2C2C srgb(44,44,44)
45: ( 45, 45, 45) #2D2D2D srgb(45,45,45)
46: ( 46, 46, 46) #2E2E2E grey18
47: ( 47, 47, 47) #2F2F2F srgb(47,47,47)
48: ( 48, 48, 48) #303030 grey19
49: ( 49, 49, 49) #313131 srgb(49,49,49)
50: ( 50, 50, 50) #323232 srgb(50,50,50)
51: ( 51, 51, 51) #333333 grey20
52: ( 52, 52, 52) #343434 srgb(52,52,52)
53: ( 53, 53, 53) #353535 srgb(53,53,53)
54: ( 54, 54, 54) #363636 grey21
55: ( 55, 55, 55) #373737 srgb(55,55,55)
56: ( 56, 56, 56) #383838 grey22
57: ( 57, 57, 57) #393939 srgb(57,57,57)
58: ( 58, 58, 58) #3A3A3A srgb(58,58,58)
59: ( 59, 59, 59) #3B3B3B grey23
60: ( 60, 60, 60) #3C3C3C srgb(60,60,60)
61: ( 61, 61, 61) #3D3D3D grey24
62: ( 62, 62, 62) #3E3E3E srgb(62,62,62)
63: ( 63, 63, 63) #3F3F3F srgb(63,63,63)
64: ( 64, 64, 64) #404040 grey25
65: ( 65, 65, 65) #414141 srgb(65,65,65)
66: ( 66, 66, 66) #424242 grey26
67: ( 67, 67, 67) #434343 srgb(67,67,67)
68: ( 68, 68, 68) #444444 srgb(68,68,68)
69: ( 69, 69, 69) #454545 grey27
70: ( 70, 70, 70) #464646 srgb(70,70,70)
71: ( 71, 71, 71) #474747 grey28
72: ( 72, 72, 72) #484848 srgb(72,72,72)
73: ( 73, 73, 73) #494949 srgb(73,73,73)
74: ( 74, 74, 74) #4A4A4A grey29
75: ( 75, 75, 75) #4B4B4B srgb(75,75,75)
76: ( 76, 76, 76) #4C4C4C srgb(76,76,76)
77: ( 77, 77, 77) #4D4D4D grey30
78: ( 78, 78, 78) #4E4E4E srgb(78,78,78)
79: ( 79, 79, 79) #4F4F4F grey31
80: ( 80, 80, 80) #505050 srgb(80,80,80)
81: ( 81, 81, 81) #515151 srgb(81,81,81)
82: ( 82, 82, 82) #525252 grey32
83: ( 83, 83, 83) #535353 srgb(83,83,83)
84: ( 84, 84, 84) #545454 grey33
85: ( 85, 85, 85) #555555 srgb(85,85,85)
86: ( 86, 86, 86) #565656 srgb(86,86,86)
87: ( 87, 87, 87) #575757 grey34
88: ( 88, 88, 88) #585858 srgb(88,88,88)
89: ( 89, 89, 89) #595959 grey35
90: ( 90, 90, 90) #5A5A5A srgb(90,90,90)
91: ( 91, 91, 91) #5B5B5B srgb(91,91,91)
92: ( 92, 92, 92) #5C5C5C grey36
93: ( 93, 93, 93) #5D5D5D srgb(93,93,93)
94: ( 94, 94, 94) #5E5E5E grey37
95: ( 95, 95, 95) #5F5F5F srgb(95,95,95)
96: ( 96, 96, 96) #606060 srgb(96,96,96)
97: ( 97, 97, 97) #616161 grey38
98: ( 98, 98, 98) #626262 srgb(98,98,98)
99: ( 99, 99, 99) #636363 grey39
100: (100,100,100) #646464 srgb(100,100,100)
101: (101,101,101) #656565 srgb(101,101,101)
102: (102,102,102) #666666 grey40
103: (103,103,103) #676767 srgb(103,103,103)
104: (104,104,104) #686868 srgb(104,104,104)
105: (105,105,105) #696969 DimGray
106: (106,106,106) #6A6A6A srgb(106,106,106)
107: (107,107,107) #6B6B6B grey42
108: (108,108,108) #6C6C6C srgb(108,108,108)
109: (109,109,109) #6D6D6D srgb(109,109,109)
110: (110,110,110) #6E6E6E grey43
111: (111,111,111) #6F6F6F srgb(111,111,111)
112: (112,112,112) #707070 grey44
113: (113,113,113) #717171 srgb(113,113,113)
114: (114,114,114) #727272 srgb(114,114,114)
115: (115,115,115) #737373 grey45
116: (116,116,116) #747474 srgb(116,116,116)
117: (117,117,117) #757575 grey46
118: (118,118,118) #767676 srgb(118,118,118)
119: (119,119,119) #777777 srgb(119,119,119)
120: (120,120,120) #787878 grey47
121: (121,121,121) #797979 srgb(121,121,121)
122: (122,122,122) #7A7A7A grey48
123: (123,123,123) #7B7B7B srgb(123,123,123)
124: (124,124,124) #7C7C7C srgb(124,124,124)
125: (125,125,125) #7D7D7D grey49
126: (126,126,126) #7E7E7E gray
127: (127,127,127) #7F7F7F grey50
128: (128,128,128) #808080 fractal
129: (129,129,129) #818181 srgb(129,129,129)
130: (130,130,130) #828282 grey51
131: (131,131,131) #838383 srgb(131,131,131)
132: (132,132,132) #848484 srgb(132,132,132)
133: (133,133,133) #858585 grey52
134: (134,134,134) #868686 srgb(134,134,134)
135: (135,135,135) #878787 grey53
136: (136,136,136) #888888 srgb(136,136,136)
137: (137,137,137) #898989 srgb(137,137,137)
138: (138,138,138) #8A8A8A grey54
139: (139,139,139) #8B8B8B srgb(139,139,139)
140: (140,140,140) #8C8C8C grey55
141: (141,141,141) #8D8D8D srgb(141,141,141)
142: (142,142,142) #8E8E8E srgb(142,142,142)
143: (143,143,143) #8F8F8F grey56
144: (144,144,144) #909090 srgb(144,144,144)
145: (145,145,145) #919191 grey57
146: (146,146,146) #929292 srgb(146,146,146)
147: (147,147,147) #939393 srgb(147,147,147)
148: (148,148,148) #949494 grey58
149: (149,149,149) #959595 srgb(149,149,149)
150: (150,150,150) #969696 grey59
151: (151,151,151) #979797 srgb(151,151,151)
152: (152,152,152) #989898 srgb(152,152,152)
153: (153,153,153) #999999 grey60
154: (154,154,154) #9A9A9A srgb(154,154,154)
155: (155,155,155) #9B9B9B srgb(155,155,155)
156: (156,156,156) #9C9C9C grey61
157: (157,157,157) #9D9D9D srgb(157,157,157)
158: (158,158,158) #9E9E9E grey62
159: (159,159,159) #9F9F9F srgb(159,159,159)
160: (160,160,160) #A0A0A0 srgb(160,160,160)
161: (161,161,161) #A1A1A1 grey63
162: (162,162,162) #A2A2A2 srgb(162,162,162)
163: (163,163,163) #A3A3A3 grey64
164: (164,164,164) #A4A4A4 srgb(164,164,164)
165: (165,165,165) #A5A5A5 srgb(165,165,165)
166: (166,166,166) #A6A6A6 grey65
167: (167,167,167) #A7A7A7 srgb(167,167,167)
168: (168,168,168) #A8A8A8 grey66
169: (169,169,169) #A9A9A9 DarkGray
170: (170,170,170) #AAAAAA srgb(170,170,170)
171: (171,171,171) #ABABAB grey67
172: (172,172,172) #ACACAC srgb(172,172,172)
173: (173,173,173) #ADADAD grey68
174: (174,174,174) #AEAEAE srgb(174,174,174)
175: (175,175,175) #AFAFAF srgb(175,175,175)
176: (176,176,176) #B0B0B0 grey69
177: (177,177,177) #B1B1B1 srgb(177,177,177)
178: (178,178,178) #B2B2B2 srgb(178,178,178)
179: (179,179,179) #B3B3B3 grey70
180: (180,180,180) #B4B4B4 srgb(180,180,180)
181: (181,181,181) #B5B5B5 grey71
182: (182,182,182) #B6B6B6 srgb(182,182,182)
183: (183,183,183) #B7B7B7 srgb(183,183,183)
184: (184,184,184) #B8B8B8 grey72
185: (185,185,185) #B9B9B9 srgb(185,185,185)
186: (186,186,186) #BABABA grey73
187: (187,187,187) #BBBBBB srgb(187,187,187)
188: (188,188,188) #BCBCBC srgb(188,188,188)
189: (189,189,189) #BDBDBD grey74
190: (190,190,190) #BEBEBE grey
191: (191,191,191) #BFBFBF grey75
192: (192,192,192) #C0C0C0 silver
193: (193,193,193) #C1C1C1 srgb(193,193,193)
194: (194,194,194) #C2C2C2 grey76
195: (195,195,195) #C3C3C3 srgb(195,195,195)
196: (196,196,196) #C4C4C4 grey77
197: (197,197,197) #C5C5C5 srgb(197,197,197)
198: (198,198,198) #C6C6C6 srgb(198,198,198)
199: (199,199,199) #C7C7C7 grey78
200: (200,200,200) #C8C8C8 srgb(200,200,200)
201: (201,201,201) #C9C9C9 grey79
202: (202,202,202) #CACACA srgb(202,202,202)
203: (203,203,203) #CBCBCB srgb(203,203,203)
204: (204,204,204) #CCCCCC grey80
205: (205,205,205) #CDCDCD srgb(205,205,205)
206: (206,206,206) #CECECE srgb(206,206,206)
207: (207,207,207) #CFCFCF grey81
208: (208,208,208) #D0D0D0 srgb(208,208,208)
209: (209,209,209) #D1D1D1 grey82
210: (210,210,210) #D2D2D2 srgb(210,210,210)
211: (211,211,211) #D3D3D3 LightGray
212: (212,212,212) #D4D4D4 grey83
213: (213,213,213) #D5D5D5 srgb(213,213,213)
214: (214,214,214) #D6D6D6 grey84
215: (215,215,215) #D7D7D7 srgb(215,215,215)
216: (216,216,216) #D8D8D8 srgb(216,216,216)
217: (217,217,217) #D9D9D9 grey85
218: (218,218,218) #DADADA srgb(218,218,218)
219: (219,219,219) #DBDBDB grey86
220: (220,220,220) #DCDCDC gainsboro
221: (221,221,221) #DDDDDD srgb(221,221,221)
222: (222,222,222) #DEDEDE grey87
223: (223,223,223) #DFDFDF srgb(223,223,223)
224: (224,224,224) #E0E0E0 grey88
225: (225,225,225) #E1E1E1 srgb(225,225,225)
226: (226,226,226) #E2E2E2 srgb(226,226,226)
227: (227,227,227) #E3E3E3 grey89
228: (228,228,228) #E4E4E4 srgb(228,228,228)
229: (229,229,229) #E5E5E5 grey90
230: (230,230,230) #E6E6E6 srgb(230,230,230)
231: (231,231,231) #E7E7E7 srgb(231,231,231)
232: (232,232,232) #E8E8E8 grey91
233: (233,233,233) #E9E9E9 srgb(233,233,233)
234: (234,234,234) #EAEAEA srgb(234,234,234)
235: (235,235,235) #EBEBEB grey92
236: (236,236,236) #ECECEC srgb(236,236,236)
237: (237,237,237) #EDEDED grey93
238: (238,238,238) #EEEEEE srgb(238,238,238)
239: (239,239,239) #EFEFEF srgb(239,239,239)
240: (240,240,240) #F0F0F0 grey94
241: (241,241,241) #F1F1F1 srgb(241,241,241)
242: (242,242,242) #F2F2F2 grey95
243: (243,243,243) #F3F3F3 srgb(243,243,243)
244: (244,244,244) #F4F4F4 srgb(244,244,244)
245: (245,245,245) #F5F5F5 grey96
246: (246,246,246) #F6F6F6 srgb(246,246,246)
247: (247,247,247) #F7F7F7 grey97
248: (248,248,248) #F8F8F8 srgb(248,248,248)
249: (249,249,249) #F9F9F9 srgb(249,249,249)
250: (250,250,250) #FAFAFA grey98
251: (251,251,251) #FBFBFB srgb(251,251,251)
252: (252,252,252) #FCFCFC grey99
253: (253,253,253) #FDFDFD srgb(253,253,253)
254: (254,254,254) #FEFEFE srgb(254,254,254)
255: (255,255,255) #FFFFFF white
Rendering intent: Perceptual
Gamma: 0.454545
Chromaticity:
red primary: (0.64,0.33)
green primary: (0.3,0.6)
blue primary: (0.15,0.06)
white point: (0.3127,0.329)
Interlace: None
Background color: white
Border color: srgb(223,223,223)
Matte color: grey74
Transparent color: black
Compose: Over
Page geometry: 128x128+0+0
Dispose: Undefined
Iterations: 0
Compression: None
Orientation: Undefined
Properties:
date:create:
date:modify:
label: images/image.rgba
signature:
Artifacts:
filename: image.rgba
verbose: true
Tainted: False
Filesize: 33.3KB
Number pixels: 16.4K
Pixels per second: 16.384EB
User time: 0.010u
Elapsed time: 0:01.000
Version: ImageMagick 6.8.0-7 2012-11-30 Q16 http://www.imagemagick.org
convert -brightness-contrast 15x5 sgi:image.rgba sgi:generated/image.rgba
