Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  PNG Driver
       4             :  * Purpose:  Implement GDAL PNG Support
       5             :  * Author:   Frank Warmerdam, warmerda@home.com
       6             :  *
       7             :  ******************************************************************************
       8             :  * Copyright (c) 2000, Frank Warmerdam
       9             :  * Copyright (c) 2007-2014, Even Rouault <even dot rouault at spatialys.com>
      10             :  *
      11             :  * SPDX-License-Identifier: MIT
      12             :  ******************************************************************************/
      13             : 
      14             : #include "pngdrivercore.h"
      15             : 
      16             : /************************************************************************/
      17             : /*                     PNGDriverIdentify()                              */
      18             : /************************************************************************/
      19             : 
      20       70803 : int PNGDriverIdentify(GDALOpenInfo *poOpenInfo)
      21             : 
      22             : {
      23       70803 :     constexpr GByte png_signature[] = {137, 80, 78, 71, 13, 10, 26, 10};
      24       70803 :     if (poOpenInfo->fpL == nullptr ||
      25       17636 :         poOpenInfo->nHeaderBytes < static_cast<int>(sizeof(png_signature)))
      26       53441 :         return FALSE;
      27             : 
      28       17362 :     if (memcmp(poOpenInfo->pabyHeader, png_signature, sizeof(png_signature)) !=
      29             :         0)
      30        7060 :         return FALSE;
      31             : 
      32       10302 :     return TRUE;
      33             : }
      34             : 
      35             : /************************************************************************/
      36             : /*                      PNGDriverSetCommonMetadata()                    */
      37             : /************************************************************************/
      38             : 
      39        1339 : void PNGDriverSetCommonMetadata(GDALDriver *poDriver)
      40             : {
      41        1339 :     poDriver->SetDescription(DRIVER_NAME);
      42        1339 :     poDriver->SetMetadataItem(GDAL_DCAP_RASTER, "YES");
      43        1339 :     poDriver->SetMetadataItem(GDAL_DMD_LONGNAME, "Portable Network Graphics");
      44        1339 :     poDriver->SetMetadataItem(GDAL_DMD_HELPTOPIC, "drivers/raster/png.html");
      45        1339 :     poDriver->SetMetadataItem(GDAL_DMD_EXTENSION, "png");
      46        1339 :     poDriver->SetMetadataItem(GDAL_DMD_MIMETYPE, "image/png");
      47             : 
      48        1339 :     poDriver->SetMetadataItem(GDAL_DMD_CREATIONDATATYPES, "Byte UInt16");
      49        1339 :     poDriver->SetMetadataItem(
      50             :         GDAL_DMD_CREATIONOPTIONLIST,
      51             :         "<CreationOptionList>\n"
      52             :         "   <Option name='WORLDFILE' type='boolean' description='Create world "
      53             :         "file' default='FALSE'/>\n"
      54             :         "   <Option name='ZLEVEL' type='int' description='DEFLATE compression "
      55             :         "level 1-9' default='6'/>\n"
      56             :         "   <Option name='SOURCE_ICC_PROFILE' type='string' description='ICC "
      57             :         "Profile'/>\n"
      58             :         "   <Option name='SOURCE_ICC_PROFILE_NAME' type='string' "
      59             :         "description='ICC Profile name'/>\n"
      60             :         "   <Option name='SOURCE_PRIMARIES_RED' type='string' "
      61             :         "description='x,y,1.0 (xyY) red chromaticity'/>\n"
      62             :         "   <Option name='SOURCE_PRIMARIES_GREEN' type='string' "
      63             :         "description='x,y,1.0 (xyY) green chromaticity'/>\n"
      64             :         "   <Option name='SOURCE_PRIMARIES_BLUE' type='string' "
      65             :         "description='x,y,1.0 (xyY) blue chromaticity'/>\n"
      66             :         "   <Option name='SOURCE_WHITEPOINT' type='string' "
      67             :         "description='x,y,1.0 (xyY) whitepoint'/>\n"
      68             :         "   <Option name='PNG_GAMMA' type='string' description='Gamma'/>\n"
      69             :         "   <Option name='TITLE' type='string' description='Title'/>\n"
      70             :         "   <Option name='DESCRIPTION' type='string' "
      71             :         "description='Description'/>\n"
      72             :         "   <Option name='COPYRIGHT' type='string' description='Copyright'/>\n"
      73             :         "   <Option name='COMMENT' type='string' description='Comment'/>\n"
      74             :         "   <Option name='WRITE_METADATA_AS_TEXT' type='boolean' "
      75             :         "description='Whether to write source dataset metadata in TEXT chunks' "
      76             :         "default='FALSE'/>\n"
      77             :         "   <Option name='NBITS' type='int' description='Force output bit "
      78             :         "depth: 1, 2 or 4'/>\n"
      79        1339 :         "</CreationOptionList>\n");
      80             : 
      81        1339 :     poDriver->SetMetadataItem(GDAL_DCAP_VIRTUALIO, "YES");
      82             : 
      83        1339 :     poDriver->pfnIdentify = PNGDriverIdentify;
      84        1339 :     poDriver->SetMetadataItem(GDAL_DCAP_OPEN, "YES");
      85        1339 :     poDriver->SetMetadataItem(GDAL_DCAP_CREATECOPY, "YES");
      86        1339 : }
      87             : 
      88             : /************************************************************************/
      89             : /*                     DeclareDeferredPNGPlugin()                       */
      90             : /************************************************************************/
      91             : 
      92             : #ifdef PLUGIN_FILENAME
      93        1595 : void DeclareDeferredPNGPlugin()
      94             : {
      95        1595 :     if (GDALGetDriverByName(DRIVER_NAME) != nullptr)
      96             :     {
      97         302 :         return;
      98             :     }
      99        1293 :     auto poDriver = new GDALPluginDriverProxy(PLUGIN_FILENAME);
     100             : #ifdef PLUGIN_INSTALLATION_MESSAGE
     101             :     poDriver->SetMetadataItem(GDAL_DMD_PLUGIN_INSTALLATION_MESSAGE,
     102             :                               PLUGIN_INSTALLATION_MESSAGE);
     103             : #endif
     104        1293 :     PNGDriverSetCommonMetadata(poDriver);
     105        1293 :     GetGDALDriverManager()->DeclareDeferredPluginDriver(poDriver);
     106             : }
     107             : #endif