1 : /******************************************************************************
2 : * $Id: gdalnodatamaskband.cpp 19692 2010-05-13 17:16:55Z rouault $
3 : *
4 : * Project: GDAL Core
5 : * Purpose: Implementation of GDALNoDataMaskBand, a class implementing all
6 : * a default band mask based on nodata values.
7 : * Author: Frank Warmerdam, warmerdam@pobox.com
8 : *
9 : ******************************************************************************
10 : * Copyright (c) 2007, Frank Warmerdam
11 : *
12 : * Permission is hereby granted, free of charge, to any person obtaining a
13 : * copy of this software and associated documentation files (the "Software"),
14 : * to deal in the Software without restriction, including without limitation
15 : * the rights to use, copy, modify, merge, publish, distribute, sublicense,
16 : * and/or sell copies of the Software, and to permit persons to whom the
17 : * Software is furnished to do so, subject to the following conditions:
18 : *
19 : * The above copyright notice and this permission notice shall be included
20 : * in all copies or substantial portions of the Software.
21 : *
22 : * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
23 : * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 : * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25 : * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26 : * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27 : * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
28 : * DEALINGS IN THE SOFTWARE.
29 : ****************************************************************************/
30 :
31 : #include "gdal_priv.h"
32 :
33 : CPL_CVSID("$Id: gdalnodatamaskband.cpp 19692 2010-05-13 17:16:55Z rouault $");
34 :
35 : /************************************************************************/
36 : /* GDALNoDataMaskBand() */
37 : /************************************************************************/
38 :
39 76 : GDALNoDataMaskBand::GDALNoDataMaskBand( GDALRasterBand *poParent )
40 :
41 : {
42 76 : poDS = NULL;
43 76 : nBand = 0;
44 :
45 76 : nRasterXSize = poParent->GetXSize();
46 76 : nRasterYSize = poParent->GetYSize();
47 :
48 76 : eDataType = GDT_Byte;
49 76 : poParent->GetBlockSize( &nBlockXSize, &nBlockYSize );
50 :
51 76 : this->poParent = poParent;
52 76 : dfNoDataValue = poParent->GetNoDataValue();
53 76 : }
54 :
55 : /************************************************************************/
56 : /* ~GDALNoDataMaskBand() */
57 : /************************************************************************/
58 :
59 76 : GDALNoDataMaskBand::~GDALNoDataMaskBand()
60 :
61 : {
62 76 : }
63 :
64 : /************************************************************************/
65 : /* IReadBlock() */
66 : /************************************************************************/
67 :
68 : CPLErr GDALNoDataMaskBand::IReadBlock( int nXBlockOff, int nYBlockOff,
69 29 : void * pImage )
70 :
71 : {
72 : GDALDataType eWrkDT;
73 :
74 : /* -------------------------------------------------------------------- */
75 : /* Decide on a working type. */
76 : /* -------------------------------------------------------------------- */
77 29 : switch( poParent->GetRasterDataType() )
78 : {
79 : case GDT_Byte:
80 7 : eWrkDT = GDT_Byte;
81 7 : break;
82 :
83 : case GDT_UInt16:
84 : case GDT_UInt32:
85 2 : eWrkDT = GDT_UInt32;
86 2 : break;
87 :
88 : case GDT_Int16:
89 : case GDT_Int32:
90 : case GDT_CInt16:
91 : case GDT_CInt32:
92 16 : eWrkDT = GDT_Int32;
93 16 : break;
94 :
95 : case GDT_Float32:
96 : case GDT_CFloat32:
97 2 : eWrkDT = GDT_Float32;
98 2 : break;
99 :
100 : case GDT_Float64:
101 : case GDT_CFloat64:
102 2 : eWrkDT = GDT_Float64;
103 2 : break;
104 :
105 : default:
106 0 : CPLAssert( FALSE );
107 0 : eWrkDT = GDT_Float64;
108 : break;
109 : }
110 :
111 : /* -------------------------------------------------------------------- */
112 : /* Read the image data. */
113 : /* -------------------------------------------------------------------- */
114 : GByte *pabySrc;
115 : CPLErr eErr;
116 :
117 29 : pabySrc = (GByte *) VSIMalloc3( GDALGetDataTypeSize(eWrkDT)/8, nBlockXSize, nBlockYSize );
118 29 : if (pabySrc == NULL)
119 : {
120 : CPLError( CE_Failure, CPLE_OutOfMemory,
121 0 : "GDALNoDataMaskBand::IReadBlock: Out of memory for buffer." );
122 0 : return CE_Failure;
123 : }
124 :
125 :
126 29 : int nXSizeRequest = nBlockXSize;
127 29 : if (nXBlockOff * nBlockXSize + nBlockXSize > nRasterXSize)
128 0 : nXSizeRequest = nRasterXSize - nXBlockOff * nBlockXSize;
129 29 : int nYSizeRequest = nBlockYSize;
130 29 : if (nYBlockOff * nBlockYSize + nBlockYSize > nRasterYSize)
131 0 : nYSizeRequest = nRasterYSize - nYBlockOff * nBlockYSize;
132 :
133 29 : if (nXSizeRequest != nBlockXSize || nYSizeRequest != nBlockYSize)
134 : {
135 : /* memset the whole buffer to avoid Valgrind warnings in case we can't */
136 : /* fetch a full block */
137 0 : memset(pabySrc, 0, GDALGetDataTypeSize(eWrkDT)/8 * nBlockXSize * nBlockYSize );
138 : }
139 :
140 : eErr = poParent->RasterIO( GF_Read,
141 : nXBlockOff * nBlockXSize, nYBlockOff * nBlockYSize,
142 : nXSizeRequest, nYSizeRequest,
143 : pabySrc, nXSizeRequest, nYSizeRequest,
144 29 : eWrkDT, 0, nBlockXSize * (GDALGetDataTypeSize(eWrkDT)/8) );
145 29 : if( eErr != CE_None )
146 0 : return eErr;
147 :
148 29 : int bIsNoDataNan = CPLIsNan(dfNoDataValue);
149 :
150 : /* -------------------------------------------------------------------- */
151 : /* Process different cases. */
152 : /* -------------------------------------------------------------------- */
153 : int i;
154 29 : switch( eWrkDT )
155 : {
156 : case GDT_Byte:
157 : {
158 7 : GByte byNoData = (GByte) dfNoDataValue;
159 :
160 2408 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
161 : {
162 2401 : if( pabySrc[i] == byNoData )
163 158 : ((GByte *) pImage)[i] = 0;
164 : else
165 2243 : ((GByte *) pImage)[i] = 255;
166 : }
167 : }
168 7 : break;
169 :
170 : case GDT_UInt32:
171 : {
172 2 : GUInt32 nNoData = (GUInt32) dfNoDataValue;
173 :
174 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
175 : {
176 2 : if( ((GUInt32 *)pabySrc)[i] == nNoData )
177 2 : ((GByte *) pImage)[i] = 0;
178 : else
179 0 : ((GByte *) pImage)[i] = 255;
180 : }
181 : }
182 2 : break;
183 :
184 : case GDT_Int32:
185 : {
186 16 : GInt32 nNoData = (GInt32) dfNoDataValue;
187 :
188 88 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
189 : {
190 72 : if( ((GInt32 *)pabySrc)[i] == nNoData )
191 18 : ((GByte *) pImage)[i] = 0;
192 : else
193 54 : ((GByte *) pImage)[i] = 255;
194 : }
195 : }
196 16 : break;
197 :
198 : case GDT_Float32:
199 : {
200 2 : float fNoData = (float) dfNoDataValue;
201 :
202 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
203 : {
204 2 : float fVal =((float *)pabySrc)[i];
205 2 : if( bIsNoDataNan && CPLIsNan(fVal))
206 0 : ((GByte *) pImage)[i] = 0;
207 4 : else if( EQUAL_TO_NODATA(fVal, fNoData) )
208 2 : ((GByte *) pImage)[i] = 0;
209 : else
210 0 : ((GByte *) pImage)[i] = 255;
211 : }
212 : }
213 2 : break;
214 :
215 : case GDT_Float64:
216 : {
217 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
218 : {
219 2 : double dfVal =((double *)pabySrc)[i];
220 2 : if( bIsNoDataNan && CPLIsNan(dfVal))
221 0 : ((GByte *) pImage)[i] = 0;
222 4 : else if( EQUAL_TO_NODATA(dfVal, dfNoDataValue) )
223 2 : ((GByte *) pImage)[i] = 0;
224 : else
225 0 : ((GByte *) pImage)[i] = 255;
226 : }
227 : }
228 2 : break;
229 :
230 : default:
231 0 : CPLAssert( FALSE );
232 : break;
233 : }
234 :
235 29 : CPLFree( pabySrc );
236 :
237 29 : return CE_None;
238 : }
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