[GRASS-dev] [GRASS GIS] #73: r.out.gdal tiff output does not work
GRASS GIS
trac at osgeo.org
Sun Aug 19 12:33:25 PDT 2012
#73: r.out.gdal tiff output does not work
---------------------+------------------------------------------------------
Reporter: helena | Owner: grass-dev@…
Type: defect | Status: closed
Priority: major | Milestone: 6.4.1
Component: Raster | Version: svn-trunk
Resolution: fixed | Keywords: r.out.gdal, tiff
Platform: All | Cpu: All
---------------------+------------------------------------------------------
Changes (by mmetz):
* status: new => closed
* resolution: => fixed
Comment:
Replying to [comment:58 neteler]:
> Replying to [comment:57 mmetz]:
> > Replying to [comment:56 hamish]:
> > > is this one now done?
> > >
> > Should be, in all branches.
>
> Can the ticket be closed then?
This dreadful ticket should have been closed a long time ago. The last
changes related to this ticket have been made some years ago. No one
complained. Closing ticket.
>
> > > aside: do grass tiff-metadata colors now appear in qgis
automagically?
>
> To my knowledge yes.
No. The last QGIS version that was reading GRASS metadata color rules was,
as far as I can tell, 0.9.1, the best QGIS version ever. QGIS 1.7 and QGIS
1.8 do not read GRASS color rules. They only read GeoTIFF color tables,
not GRASS color rules. Please open a new ticket if need be for r.in.gdal
and/or QGIS.
The GRASS module r.in.gdal as well as QGIS versions 1.7.4 and 1.8.0 read
color tables but not GRASS color rules.
An illustration for the difference between a color rule and a color table:
This is the GRASS color rule "grey255":
{{{
0 0:0:0
255 255:255:255
}}}
This is the equivalent standard GeoTIFF color table:
{{{
000:000:000
001:001:001
002:002:002
003:003:003
004:004:004
005:005:005
006:006:006
007:007:007
008:008:008
009:009:009
010:010:010
011:011:011
012:012:012
013:013:013
014:014:014
015:015:015
016:016:016
017:017:017
018:018:018
019:019:019
020:020:020
021:021:021
022:022:022
023:023:023
024:024:024
025:025:025
026:026:026
027:027:027
028:028:028
029:029:029
030:030:030
031:031:031
032:032:032
033:033:033
034:034:034
035:035:035
036:036:036
037:037:037
038:038:038
039:039:039
040:040:040
041:041:041
042:042:042
043:043:043
044:044:044
045:045:045
046:046:046
047:047:047
048:048:048
049:049:049
050:050:050
051:051:051
052:052:052
053:053:053
054:054:054
055:055:055
056:056:056
057:057:057
058:058:058
059:059:059
060:060:060
061:061:061
062:062:062
063:063:063
064:064:064
065:065:065
066:066:066
067:067:067
068:068:068
069:069:069
070:070:070
071:071:071
072:072:072
073:073:073
074:074:074
075:075:075
076:076:076
077:077:077
078:078:078
079:079:079
080:080:080
081:081:081
082:082:082
083:083:083
084:084:084
085:085:085
086:086:086
087:087:087
088:088:088
089:089:089
090:090:090
091:091:091
092:092:092
093:093:093
094:094:094
095:095:095
096:096:096
097:097:097
098:098:098
099:099:099
100:100:100
101:101:101
102:102:102
103:103:103
104:104:104
105:105:105
106:106:106
107:107:107
108:108:108
109:109:109
110:110:110
111:111:111
112:112:112
113:113:113
114:114:114
115:115:115
116:116:116
117:117:117
118:118:118
119:119:119
120:120:120
121:121:121
122:122:122
123:123:123
124:124:124
125:125:125
126:126:126
127:127:127
128:128:128
129:129:129
130:130:130
131:131:131
132:132:132
133:133:133
134:134:134
135:135:135
136:136:136
137:137:137
138:138:138
139:139:139
140:140:140
141:141:141
142:142:142
143:143:143
144:144:144
145:145:145
146:146:146
147:147:147
148:148:148
149:149:149
150:150:150
151:151:151
152:152:152
153:153:153
154:154:154
155:155:155
156:156:156
157:157:157
158:158:158
159:159:159
160:160:160
161:161:161
162:162:162
163:163:163
164:164:164
165:165:165
166:166:166
167:167:167
168:168:168
169:169:169
170:170:170
171:171:171
172:172:172
173:173:173
174:174:174
175:175:175
176:176:176
177:177:177
178:178:178
179:179:179
180:180:180
181:181:181
182:182:182
183:183:183
184:184:184
185:185:185
186:186:186
187:187:187
188:188:188
189:189:189
190:190:190
191:191:191
192:192:192
193:193:193
194:194:194
195:195:195
196:196:196
197:197:197
198:198:198
199:199:199
200:200:200
201:201:201
202:202:202
203:203:203
204:204:204
205:205:205
206:206:206
207:207:207
208:208:208
209:209:209
210:210:210
211:211:211
212:212:212
213:213:213
214:214:214
215:215:215
216:216:216
217:217:217
218:218:218
219:219:219
220:220:220
221:221:221
222:222:222
223:223:223
224:224:224
225:225:225
226:226:226
227:227:227
228:228:228
229:229:229
230:230:230
231:231:231
232:232:232
233:233:233
234:234:234
235:235:235
236:236:236
237:237:237
238:238:238
239:239:239
240:240:240
241:241:241
242:242:242
243:243:243
244:244:244
245:245:245
246:246:246
247:247:247
248:248:248
249:249:249
250:250:250
251:251:251
252:252:252
253:253:253
254:254:254
255:255:255
}}}
Guess what takes longer to interpret.
Now imagine a color table with 65,535 entries.
The problem is that both GRASS and QGIS ignore any GRASS color rules
present in the metadata and instead prefer the rather dumb color tables.
Loading a colortable with 255 or even 65,535 entries is IMHO a really bad
idea.
Any issues related to the output of r.out.gdal should be carefully
investigated. More often than not it is a limitation of the application
used to import the GRASS export, and that application might well be GRASS
itself. The output of r.out.gdal is completely in accordance with GDAL.
Markus M
--
Ticket URL: <http://trac.osgeo.org/grass/ticket/73#comment:59>
GRASS GIS <http://grass.osgeo.org>
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