1 : /******************************************************************************
2 : * $Id: gdalnodatamaskband.cpp 22857 2011-08-02 18:17:45Z 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 22857 2011-08-02 18:17:45Z rouault $");
34 :
35 : /************************************************************************/
36 : /* GDALNoDataMaskBand() */
37 : /************************************************************************/
38 :
39 89 : GDALNoDataMaskBand::GDALNoDataMaskBand( GDALRasterBand *poParent )
40 :
41 : {
42 89 : poDS = NULL;
43 89 : nBand = 0;
44 :
45 89 : nRasterXSize = poParent->GetXSize();
46 89 : nRasterYSize = poParent->GetYSize();
47 :
48 89 : eDataType = GDT_Byte;
49 89 : poParent->GetBlockSize( &nBlockXSize, &nBlockYSize );
50 :
51 89 : this->poParent = poParent;
52 89 : dfNoDataValue = poParent->GetNoDataValue();
53 89 : }
54 :
55 : /************************************************************************/
56 : /* ~GDALNoDataMaskBand() */
57 : /************************************************************************/
58 :
59 89 : GDALNoDataMaskBand::~GDALNoDataMaskBand()
60 :
61 : {
62 89 : }
63 :
64 : /************************************************************************/
65 : /* IReadBlock() */
66 : /************************************************************************/
67 :
68 29 : CPLErr GDALNoDataMaskBand::IReadBlock( int nXBlockOff, int nYBlockOff,
69 : 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 : {
147 0 : CPLFree(pabySrc);
148 0 : return eErr;
149 : }
150 :
151 29 : int bIsNoDataNan = CPLIsNan(dfNoDataValue);
152 :
153 : /* -------------------------------------------------------------------- */
154 : /* Process different cases. */
155 : /* -------------------------------------------------------------------- */
156 : int i;
157 29 : switch( eWrkDT )
158 : {
159 : case GDT_Byte:
160 : {
161 7 : GByte byNoData = (GByte) dfNoDataValue;
162 :
163 2408 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
164 : {
165 2401 : if( pabySrc[i] == byNoData )
166 158 : ((GByte *) pImage)[i] = 0;
167 : else
168 2243 : ((GByte *) pImage)[i] = 255;
169 : }
170 : }
171 7 : break;
172 :
173 : case GDT_UInt32:
174 : {
175 2 : GUInt32 nNoData = (GUInt32) dfNoDataValue;
176 :
177 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
178 : {
179 2 : if( ((GUInt32 *)pabySrc)[i] == nNoData )
180 2 : ((GByte *) pImage)[i] = 0;
181 : else
182 0 : ((GByte *) pImage)[i] = 255;
183 : }
184 : }
185 2 : break;
186 :
187 : case GDT_Int32:
188 : {
189 16 : GInt32 nNoData = (GInt32) dfNoDataValue;
190 :
191 88 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
192 : {
193 72 : if( ((GInt32 *)pabySrc)[i] == nNoData )
194 18 : ((GByte *) pImage)[i] = 0;
195 : else
196 54 : ((GByte *) pImage)[i] = 255;
197 : }
198 : }
199 16 : break;
200 :
201 : case GDT_Float32:
202 : {
203 2 : float fNoData = (float) dfNoDataValue;
204 :
205 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
206 : {
207 2 : float fVal =((float *)pabySrc)[i];
208 2 : if( bIsNoDataNan && CPLIsNan(fVal))
209 0 : ((GByte *) pImage)[i] = 0;
210 4 : else if( ARE_REAL_EQUAL(fVal, fNoData) )
211 2 : ((GByte *) pImage)[i] = 0;
212 : else
213 0 : ((GByte *) pImage)[i] = 255;
214 : }
215 : }
216 2 : break;
217 :
218 : case GDT_Float64:
219 : {
220 4 : for( i = nBlockXSize * nBlockYSize - 1; i >= 0; i-- )
221 : {
222 2 : double dfVal =((double *)pabySrc)[i];
223 2 : if( bIsNoDataNan && CPLIsNan(dfVal))
224 0 : ((GByte *) pImage)[i] = 0;
225 4 : else if( ARE_REAL_EQUAL(dfVal, dfNoDataValue) )
226 2 : ((GByte *) pImage)[i] = 0;
227 : else
228 0 : ((GByte *) pImage)[i] = 255;
229 : }
230 : }
231 2 : break;
232 :
233 : default:
234 0 : CPLAssert( FALSE );
235 : break;
236 : }
237 :
238 29 : CPLFree( pabySrc );
239 :
240 29 : return CE_None;
241 : }
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