Merge pull request NOAA-EMC#252 from NOAA-EMC/png_wne

png with large grids, add tests

CMakeLists.txt

@@ -15,7 +15,7 @@ option(USE_NETCDF "Use NetCDF" on)
 option(USE_REGEX "Use Regex?" on)
 option(USE_TIGGE "Use tigge?" on)
 option(USE_MYSQL "Use MySQL?" off)
-option(USE_IPOLATES "Use Ipolates" on)
+option(USE_IPOLATES "Use Ipolates" off)
 option(USE_UDF "Use UDF?" off)
 option(USE_OPENMP "Use OpenMP?" on)
 option(USE_PROJ4 "Use Proj4?" off)

tests/CMakeLists.txt

@@ -107,11 +107,18 @@ copy_test_data(ref_sec_len.gdaswave.t00z.wcoast.0p16.f000.grib2.txt)
 copy_test_data(ref_sec_len.simple_packing.grib2.txt)
 copy_test_data(ref_simple_packing.grib2.spread.txt)
 copy_test_data(ref_new_grid_gdt_32769.grib2)
+copy_test_data(png_4bits.png)
+copy_test_data(large_png.grb2)
+
 
 # Run these shell tests.
 shell_test(run_wgrib2_tests)
 shell_test(run_wgrib2_rpn_tests)
 
+if (USE_PNG)
+  shell_test(run_wgrib2_png_tests)
+endif()
+
 if (USE_NETCDF)
   shell_test(run_wgrib2_netcdf4_tests)
   shell_test(run_wgrib2_netcdf3_tests)

tests/run_wgrib2_png_tests.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+# This script runs a series of tests using the RPN calculator
+#
+# Alyson Stahl 5/7/2024
+
+set -e
+echo ""
+echo "*** Running wgrib2 png tests"
+
+
+
+r1="1:0:(2000,1000),lon=304.937500,lat=-27.584172,val=1"
+r2=`../wgrib2/wgrib2 data/png_4bits.png -ijlat 2000 1000`
+if [ "$r1" != "$r2" ] ; then
+  echo "failed png test1 $r2"
+  echo "expected         $r1"
+  exit 1
+fi
+
+r1="1:0:(2000,2000),lon=249.995002,lat=39.995000,val=0"
+r2=`../wgrib2/wgrib2 data/large_png.grb2 -ijlat 2000 2000`
+if [ "$r1" != "$r2" ] ; then
+  echo "failed png test2 $r2"
+  echo "expected         $r1"
+  exit 1
+fi
+
+echo "*** SUCCESS!"
+exit 0

wgrib2/dec_png_clone.c

@@ -113,8 +113,10 @@ int dec_png_clone(unsigned char *pngbuf,int *width,int *height, unsigned char *c
     png_set_read_fn(png_ptr,(png_voidp)&read_io_ptr,(png_rw_ptr)user_read_data_clone);
 /*     png_init_io(png_ptr, fptr);   */
 
-/*     Read and decode PNG stream   */
+/*     support for larger grids   */
+    png_set_user_limits(png_ptr, PNG_WIDTH_MAX, PNG_HEIGHT_MAX);
 
+/*     Read and decode PNG stream   */
     png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
 
 /*     Get pointer to each row of image data   */

wgrib2/wgrib2.h

@@ -37,6 +37,10 @@
 #endif
 #endif
 
+/* parameters to PNG encode routine */
+#define PNG_WIDTH_MAX  100000000
+#define PNG_HEIGHT_MAX 100000
+
 
 /*  1/2007 M. Schwarb unsigned int ndata */