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| Name | Type | Caption | Length | Value range |
|---|---|---|---|---|
| FILE * | String | Input file name | 1 - 192 | |
| DBIC * | Integer | Input image channel to be classified | 1 - 1 | |
| DBTC * | Integer | Input theme channel | 1 - 1 | |
| OTYP | String | Output type | 0 - 4 | MEAN | MODE Default: MEAN |
| DBOC * | Integer | Output homogeneous channel | 1 - 1 | |
| HOMTHRES | Float | Percentage threshold | 0 - 1 | Default: 0.0 |
| NCVALUE | Integer | Value for unclassified area | 0 - 1 | Default: 0 |
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FILE
Specifies the name of PCIDSK image file containing homogeneous areas to be classified.
DBIC
Specifies the input raster channel to classify for defined homogeneous areas.
The input channel must NOT be the same as the input theme channel (DBTC) or the output channel (DBOC).
DBTC
Specifies the input theme channel that defines the homogeneous areas of interest.
The input theme channel must NOT be the same as the input image channel (DBIC) or the output channel (DBOC).
OTYP
Specifies the output type of imagery.
DBOC
Specifies the output raster channel to receive the output imagery.
The output channel must NOT be the same as the input image channel (DBIC) or the input theme channel (DBTC).
HOMTHRES
Specifies the real value threshold representing the minimum acceptable percentage of pixels.
If the OTYP parameter is "MEAN", this parameter is ignored.
NCVALUE
Specifies a gray-level value to be used for the unclassified area.
If the OTYP parameter is "MEAN", this parameter is ignored.
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HOM classifies all pixels in an input image channel (DBIC) using an input theme channel (DBTC) to define the homogeneous areas of interest; up to 2048 areas may be processed.
The output image channel (DBOC) results are determined by the OTYP (Output Type) parameter. If the output type is "MEAN", the mean (or average) gray-level of the input image pixels for a defined homogeneous area will be output to the corresponding pixels in the output channel.
If the output type is "MODE", the mode (or most common gray level) in a defined homogeneous area will be used as output, only if the percentage of pixels occupied by that value exceeds a user-specified percentage threshold (HOMTHRES). Otherwise, the area in the output channel is assigned a user-specified value (NCVALUE) indicating that the area is unclassified.
If the output type is "MEAN", the HOMTHRES and NCVALUE parameters are ignored.
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Create an empty file (HOMTEST.PIX) with 16 pixels per line, 16 lines, and 4 channels.
EASI>FILE = "HOMTEST.PIX" EASI>DBSZ = 16,16 EASI>DBNC = 4 EASI>RUN CIM
(15*1 + 14*2 + 14*255 + 13*254) / 56 = 123.48
EASI>FILE = "HOMTEST.PIX" EASI>DBIC = 1 EASI>DBTC = 2 EASI>OTYP = "MEAN" EASI>DBOC = 3 EASI>RUN HOM EASI>DBIC = 3 EASI>DBIW = EASI>RUN NUM
IM:[WILSON]HOMTEST.PIX;1 [S 4PIC 16P 16L] 6-SEP-92
3: HOM Homo. classifier, DBIC=1 DBTC=2 OTYP=MEAN 09:13 6-SEP-92
Offset: ( 0, 0) Size: ( 16, 16)
1 1 1 1 1 1 1
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6
+---------------------------------------------------------------
1| 0 123 123 122 123 122 122 121 119 119 117 113 113 104 89 11
2| 0 0 123 123 122 123 122 122 121 119 119 117 113 113 104 89
3|123 0 0 123 123 122 123 122 122 121 119 119 117 113 113 104
4|123 123 0 0 123 123 122 123 122 122 121 119 119 117 113 113
5|122 123 123 0 0 123 123 122 123 122 122 121 119 119 117 113
6|123 122 123 123 0 0 123 123 122 123 122 122 121 119 119 117
7|122 123 122 123 123 0 0 123 123 122 123 122 122 121 119 119
8|122 122 123 122 123 123 0 0 123 123 122 123 122 122 121 119
9|121 122 122 123 122 123 123 0 0 123 123 122 123 122 122 121
10|119 121 122 122 123 122 123 123 0 0 123 123 122 123 122 122
11|119 119 121 122 122 123 122 123 123 0 0 123 123 122 123 122
12|117 119 119 121 122 122 123 122 123 123 0 0 123 123 122 123
13|113 117 119 119 121 122 122 123 122 123 123 0 0 123 123 122
14|113 113 117 119 119 121 122 122 123 122 123 123 0 0 123 123
15|104 113 113 117 119 119 121 122 122 123 122 123 123 0 0 123
16| 89 104 113 113 117 119 119 121 122 122 123 122 123 123 0 0
Classify the homogeneous areas defined in channel 2, using image data in channel 1, based on the MODE value for each homogeneous area and print window. For example, for all pixels where the value is 1 in channel 2, a value of 1 is written to channel 4, because the most commonly occurring gray level in channel 1 for theme class 1 is 255. There are 15 occurrences of 1 in channel 1 for class 1.
EASI>FILE = "HOMTEST.PIX" EASI>DBIC = 1 EASI>DBTC = 2 EASI>OTYP = "MODE" EASI>DBOC = 4 EASI>HOMTHRES = 0.0 EASI>NCVALUE = 0 EASI>RUN HOM EASI>DBIC = 4 EASI>DBIW = EASI>RUN NUM
IM:[WILSON]HOMTEST.PIX;1 [S 4PIC 16P 16L] 6-SEP-92
4: HOM Homo. classifier, DBIC=1 DBTC=2 OTYP=MODE 09:16 6-SEP-92
Offset: ( 0, 0) Size: ( 16, 16)
1 1 1 1 1 1 1
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6
+---------------------------------------------------------------
1| 0 1 1 2 3 4 4 5 6 6 7 8 8 10 10 11
2| 0 0 1 1 2 3 4 4 5 6 6 7 8 8 10 10
3| 1 0 0 1 1 2 3 4 4 5 6 6 7 8 8 10
4| 1 1 0 0 1 1 2 3 4 4 5 6 6 7 8 8
5| 2 1 1 0 0 1 1 2 3 4 4 5 6 6 7 8
6| 3 2 1 1 0 0 1 1 2 3 4 4 5 6 6 7
7| 4 3 2 1 1 0 0 1 1 2 3 4 4 5 6 6
8| 4 4 3 2 1 1 0 0 1 1 2 3 4 4 5 6
9| 5 4 4 3 2 1 1 0 0 1 1 2 3 4 4 5
10| 6 5 4 4 3 2 1 1 0 0 1 1 2 3 4 4
11| 6 6 5 4 4 3 2 1 1 0 0 1 1 2 3 4
12| 7 6 6 5 4 4 3 2 1 1 0 0 1 1 2 3
13| 8 7 6 6 5 4 4 3 2 1 1 0 0 1 1 2
14| 8 8 7 6 6 5 4 4 3 2 1 1 0 0 1 1
15| 10 8 8 7 6 6 5 4 4 3 2 1 1 0 0 1
16| 10 10 8 8 7 6 6 5 4 4 3 2 1 1 0 0
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