Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  GeoTIFF Driver
       4             :  * Purpose:  GDAL GeoTIFF support.
       5             :  * Author:   Frank Warmerdam, warmerdam@pobox.com
       6             :  *
       7             :  ******************************************************************************
       8             :  * Copyright (c) 1998, 2002, Frank Warmerdam <warmerdam@pobox.com>
       9             :  * Copyright (c) 2007-2015, Even Rouault <even dot rouault at spatialys dot com>
      10             :  *
      11             :  * SPDX-License-Identifier: MIT
      12             :  ****************************************************************************/
      13             : 
      14             : #include "gtiffsplitband.h"
      15             : 
      16             : #include "gtiffdataset.h"
      17             : 
      18             : /************************************************************************/
      19             : /*                           GTiffSplitBand()                           */
      20             : /************************************************************************/
      21             : 
      22      131118 : GTiffSplitBand::GTiffSplitBand(GTiffDataset *poDSIn, int nBandIn)
      23      131118 :     : GTiffRasterBand(poDSIn, nBandIn)
      24             : {
      25      131118 :     nBlockXSize = poDS->GetRasterXSize();
      26      131118 :     nBlockYSize = 1;
      27      131118 : }
      28             : 
      29             : /************************************************************************/
      30             : /*                       IGetDataCoverageStatus()                       */
      31             : /************************************************************************/
      32             : 
      33           0 : int GTiffSplitBand::IGetDataCoverageStatus(int, int, int, int, int, double *)
      34             : {
      35             :     return GDAL_DATA_COVERAGE_STATUS_UNIMPLEMENTED |
      36           0 :            GDAL_DATA_COVERAGE_STATUS_DATA;
      37             : }
      38             : 
      39             : /************************************************************************/
      40             : /*                             IReadBlock()                             */
      41             : /************************************************************************/
      42             : 
      43       78291 : CPLErr GTiffSplitBand::IReadBlock(int /* nBlockXOff */, int nBlockYOff,
      44             :                                   void *pImage)
      45             : 
      46             : {
      47       78291 :     m_poGDS->Crystalize();
      48             : 
      49             :     // Optimization when reading the same line in a contig multi-band TIFF.
      50       78291 :     if (m_poGDS->m_nPlanarConfig == PLANARCONFIG_CONTIG &&
      51       48291 :         m_poGDS->nBands > 1 && m_poGDS->m_nLoadedBlock == nBlockYOff)
      52             :     {
      53        4011 :         goto extract_band_data;
      54             :     }
      55             : 
      56       74280 :     if (m_poGDS->m_nPlanarConfig == PLANARCONFIG_CONTIG && m_poGDS->nBands > 1)
      57             :     {
      58       40276 :         if (m_poGDS->m_pabyBlockBuf == nullptr)
      59             :         {
      60          14 :             m_poGDS->m_pabyBlockBuf = static_cast<GByte *>(
      61           7 :                 VSI_MALLOC_VERBOSE(TIFFScanlineSize(m_poGDS->m_hTIFF)));
      62           7 :             if (m_poGDS->m_pabyBlockBuf == nullptr)
      63             :             {
      64           1 :                 return CE_Failure;
      65             :             }
      66             :         }
      67             :     }
      68             :     else
      69             :     {
      70       34004 :         CPLAssert(TIFFScanlineSize(m_poGDS->m_hTIFF) == nBlockXSize);
      71             :     }
      72             : 
      73             :     /* -------------------------------------------------------------------- */
      74             :     /*      Read through to target scanline.                                */
      75             :     /* -------------------------------------------------------------------- */
      76       74279 :     if (m_poGDS->m_nLoadedBlock >= nBlockYOff)
      77          33 :         m_poGDS->m_nLoadedBlock = -1;
      78             : 
      79       74279 :     if (m_poGDS->m_nPlanarConfig == PLANARCONFIG_SEPARATE &&
      80       30000 :         m_poGDS->nBands > 1)
      81             :     {
      82             :         // If we change of band, we must start reading the
      83             :         // new strip from its beginning.
      84       30000 :         if (m_poGDS->m_nLastBandRead != nBand)
      85          20 :             m_poGDS->m_nLoadedBlock = -1;
      86       30000 :         m_poGDS->m_nLastBandRead = nBand;
      87             :     }
      88             : 
      89      203674 :     while (m_poGDS->m_nLoadedBlock < nBlockYOff)
      90             :     {
      91      129397 :         ++m_poGDS->m_nLoadedBlock;
      92      194550 :         if (TIFFReadScanline(m_poGDS->m_hTIFF,
      93       61149 :                              m_poGDS->m_pabyBlockBuf ? m_poGDS->m_pabyBlockBuf
      94             :                                                      : pImage,
      95      129397 :                              m_poGDS->m_nLoadedBlock,
      96      129397 :                              (m_poGDS->m_nPlanarConfig == PLANARCONFIG_SEPARATE)
      97       64244 :                                  ? static_cast<uint16_t>(nBand - 1)
      98      129399 :                                  : 0) == -1 &&
      99           2 :             !m_poGDS->m_bIgnoreReadErrors)
     100             :         {
     101           2 :             ReportError(CE_Failure, CPLE_AppDefined,
     102             :                         "TIFFReadScanline() failed.");
     103           2 :             m_poGDS->m_nLoadedBlock = -1;
     104           2 :             return CE_Failure;
     105             :         }
     106             :     }
     107             : 
     108       74277 : extract_band_data:
     109             :     /* -------------------------------------------------------------------- */
     110             :     /*      Extract band data from contig buffer.                           */
     111             :     /* -------------------------------------------------------------------- */
     112       78288 :     if (m_poGDS->m_pabyBlockBuf != nullptr)
     113             :     {
     114       44286 :         for (int iPixel = 0, iSrcOffset = nBand - 1, iDstOffset = 0;
     115      180732 :              iPixel < nBlockXSize;
     116      136446 :              ++iPixel, iSrcOffset += m_poGDS->nBands, ++iDstOffset)
     117             :         {
     118      136446 :             static_cast<GByte *>(pImage)[iDstOffset] =
     119      136446 :                 m_poGDS->m_pabyBlockBuf[iSrcOffset];
     120             :         }
     121             :     }
     122             : 
     123       78288 :     return CE_None;
     124             : }
     125             : 
     126             : /************************************************************************/
     127             : /*                            IWriteBlock()                             */
     128             : /************************************************************************/
     129             : 
     130           0 : CPLErr GTiffSplitBand::IWriteBlock(int /* nBlockXOff */, int /* nBlockYOff */,
     131             :                                    void * /* pImage */)
     132             : 
     133             : {
     134           0 :     ReportError(CE_Failure, CPLE_AppDefined, "Split bands are read-only.");
     135           0 :     return CE_Failure;
     136             : }