# Psychtoolbox 2.55, errors reported by LoadClutTest and ClutTest (Mac OS X, Classic mode) **URL:** \ **Category:** Uncategorized\ **Created:** [March 21, 2005, 11:35pm UTC](https://psychtoolbox.discourse.group/t/psychtoolbox-2-55-errors-reported-by-loadcluttest-and-cluttest-mac-os-x-classic-mode/1063 "2005-03-21T23:35:43Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Allen\_Ingling](https://avatars.discourse-cdn.com/v4/letter/a/a183cd/32.png) [@Allen\_Ingling](https://psychtoolbox.discourse.group/u/Allen_Ingling)\ **Post date:** [March 21, 2005, 11:35pm UTC](https://psychtoolbox.discourse.group/t/psychtoolbox-2-55-errors-reported-by-loadcluttest-and-cluttest-mac-os-x-classic-mode/1063/1 "2005-03-21T23:35:43Z")
Hi, I have been testing the updated Psychtoolbox 2.55 and an error is reported by LoadClutTest and ClutTest. I am also a bit confused about references to the "gamma table" when testing "LoadClut", unless the "gamma table" and the "colour lookup table" are the same thing. I am not sure how many people will be running iPTB 2.55 in "Classic mode" on a G5, but I have attached details for Denis and Allen to look at, if interested. Perhaps 10-bit DACs are not properly supported in Classic mode. -- David Jones »loadcluttest LoadClutTest \*\*\* 's Classic Mac OS Compatibility, Mac OS 9.2.2 \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* PowerPC processor 0x13c, 332.169 Mflop/s Psychtoolbox 2.55, 12 March 2005, Matlab 5.2.1.1421 FileSharing is on. No serial port arbitration. \*\*\* Screen 0 \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* "" (.Display\_Video\_Apple\_BB200 version 1) 10 bit dacs. 2560x1600 60 Hz. Prefs: cscGetNextResolution, SetClutDriverWaitsForBlanking 0. - - - - - - - - - - - - - - - - - - - - - - - - - 8-bit gamma table. pixelSize 8. Success! GetClut==LoadClut at 8 bits. 8-bit gamma table. pixelSize 16. Success! GetClut==LoadClut at 8 bits. 8-bit gamma table. pixelSize 32. Success! GetClut==LoadClut at 8 bits. 10-bit gamma table. pixelSize 8. Failed! Values read differed (by up to 1023) from what was written: 0: LoadClut:[0 1023 230] vs. GetClut:[0 0 0] 1: LoadClut:[4 1019 492] vs. GetClut:[4 4 4] 2: LoadClut:[8 1015 853] vs. GetClut:[8 8 8] 3: LoadClut:[12 1011 451] vs. GetClut:[12 12 12] 4: LoadClut:[16 1007 132] vs. GetClut:[16 16 16] 10-bit gamma table. pixelSize 16. Failed! Values read differed (by up to 1023) from what was written: 0: LoadClut:[0 1023 152] vs. GetClut:[0 0 0] 1: LoadClut:[33 990 355] vs. GetClut:[4 4 4] 2: LoadClut:[66 957 543] vs. GetClut:[8 8 8] 3: LoadClut:[99 924 553] vs. GetClut:[12 12 12] 4: LoadClut:[132 891 546] vs. GetClut:[16 16 16] 10-bit gamma table. pixelSize 32. Failed! Values read differed (by up to 1023) from what was written: 0: LoadClut:[0 1023 534] vs. GetClut:[0 0 0] 1: LoadClut:[4 1019 737] vs. GetClut:[4 4 4] 2: LoadClut:[8 1015 789] vs. GetClut:[8 8 8] 3: LoadClut:[12 1011 181] vs. GetClut:[12 12 12] 4: LoadClut:[16 1007 586] vs. GetClut:[16 16 16] \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* \*\* »cluttest ClutTest \*\*\* 's Classic Mac OS Compatibility, Mac OS 9.2.2 \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* PowerPC processor 0x13c, 330.784 Mflop/s Psychtoolbox 2.55, 12 March 2005, Matlab 5.2.1.1421 FileSharing is on. No serial port arbitration. \*\*\* Screen 0 \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* "" (.Display\_Video\_Apple\_BB200 version 1) 10 bit dacs. 2560x1600 60 Hz. Prefs: cscGetNextResolution, SetClutDriverWaitsForBlanking 0. - - - - - - - - - - - - - - - - - - - - - - - - - pixelSize 8. randomize 0. SetGamma 8 bits. GetGamma 8 bits. GetClut == predicted. pixelSize 8. randomize 1. SetGamma 8 bits. GetGamma 8 bits. GetClut != predicted. Max error 244. Rms error 106.2. 0: GetClut:[91 106 142] vs. expected:[93 180 123] 1: GetClut:[237 3 34] vs. expected:[240 215 249] 2: GetClut:[88 219 223] vs. expected:[85 96 45] 3: GetClut:[196 122 49] vs. expected:[43 139 234] . . . 252: GetClut:[96 218 5] vs. expected:[70 188 106] 253: GetClut:[78 132 189] vs. expected:[236 112 178] 254: GetClut:[75 98 204] vs. expected:[238 69 94] 255: GetClut:[63 253 195] vs. expected:[68 202 165] pixelSize 16. randomize 0. SetGamma 8 bits. GetGamma 8 bits. GetClut == predicted. pixelSize 16. randomize 1. SetGamma 8 bits. GetGamma 8 bits. GetClut != predicted. Max error 241. Rms error 137.2. 0: GetClut:[7 31 10] vs. expected:[39 131 183] 1: GetClut:[7 4 1] vs. expected:[39 121 242] 2: GetClut:[2 17 9] vs. expected:[171 2 223] 3: GetClut:[10 24 19] vs. expected:[183 57 98] . . . 28: GetClut:[6 11 29] vs. expected:[125 70 90] 29: GetClut:[24 7 19] vs. expected:[57 39 98] 30: GetClut:[27 4 0] vs. expected:[146 121 209] 31: GetClut:[6 0 4] vs. expected:[125 209 121] pixelSize 32. randomize 0. SetGamma 8 bits. GetGamma 8 bits. GetClut == predicted. pixelSize 32. randomize 1. SetGamma 8 bits. GetGamma 8 bits. GetClut != predicted. Max error 240. Rms error 105.4. 0: GetClut:[132 52 214] vs. expected:[160 113 10] 1: GetClut:[19 111 160] vs. expected:[207 92 242] 2: GetClut:[65 247 163] vs. expected:[115 24 20] 3: GetClut:[220 30 10] vs. expected:[54 223 247] . . . 252: GetClut:[238 109 237] vs. expected:[251 126 215] 253: GetClut:[18 149 205] vs. expected:[35 134 58] 254: GetClut:[185 157 38] vs. expected:[53 242 42] 255: GetClut:[251 177 61] vs. expected:[213 255 25] pixelSize 8. randomize 0. SetGamma 10 bits. GetGamma 8 bits. Error in gamma table. 0 != 0 4 != 0 8 != 1 12 != 2 pixelSize 16. randomize 0. SetGamma 10 bits. GetGamma 8 bits. Error in gamma table. 0 != 0 4 != 0 8 != 1 12 != 2 pixelSize 32. randomize 0. SetGamma 10 bits. GetGamma 8 bits. Error in gamma table. 0 != 0 4 != 0 8 != 1 12 != 2 Errors encountered at all tested gamma table resolutions: 8 10 bits. \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* \*\*