WSL/SLF GitLab Repository

PNGIO.cc 23.6 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
/***********************************************************************************/
/*  Copyright 2009 WSL Institute for Snow and Avalanche Research    SLF-DAVOS      */
/***********************************************************************************/
/* This file is part of MeteoIO.
    MeteoIO is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    MeteoIO is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with MeteoIO.  If not, see <http://www.gnu.org/licenses/>.
*/
#include "PNGIO.h"
#include <meteoio/ResamplingAlgorithms2D.h>
20
#include <meteoio/Graphics.h>
21
22

#include <algorithm>
23
#include <errno.h>
24
25
26
27
28

using namespace std;

namespace mio {
/**
29
 * @page pngio PNGIO
30
 * @section template_format Format
31
32
33
34
 * This plugin write data to the Portable Network Graphics format (see https://secure.wikimedia.org/wikipedia/en/wiki/Portable_Network_Graphics).
 * No data read has been implemented, because reading an existing file would require the exact knowlege of the color gradient that has been used
 * to create it. When writing grids, various color gradients will be used depending on the parameter that the data represents. Nodata values
 * are represented by transparent pixels (transparency is acheived through a transparent color instead of a true alpha channel for size and performance).
35
 * Finally, the naming scheme for meteo grids should be: YYYYMMDDHHmm_{MeteoGrids::Parameters}.png
36
37
 *
 * @section template_units Units
38
 * All units are MKSA except temperatures that are expressed in celcius.
39
40
41
 *
 * @section template_keywords Keywords
 * This plugin uses the following keywords:
42
43
 * - COORDSYS: input coordinate system (see Coords) specified in the [Output] section
 * - COORDPARAM: extra input coordinates parameters (see Coords) specified in the [Output] section
44
45
46
47
48
49
50
 * - GRID2DPATH: meteo grids directory where to read the grids; [Output] section
 * - PNG_LEGEND: plot legend on the side of the graph? (default: true)
 * - PNG_MIN_SIZE: guarantee that a 2D plot will have at least the given size
 * - PNG_MAX_SIZE: guarantee that a 2D plot will have at most the given size
 * - PNG_SCALING: scaling algorithm, either nearest or bilinear (default=bilinear)
 * - PNG_AUTOSCALE: autoscale for the color gradient? (default=true)
 * - PNG_WORLD_FILE: create world file with each file? (default=false)
51
52
 *
 * The size are specified as width followed by height, with the separator being either a space, 'x' or '*'. If a minimum and a maximum size are given, the average of the smallest and largest permissible sizes will be used.
53
54
55
56
57
58
59
60
61
62
63
 * The world file is used for geolocalization and goes alongside the graphics output. By convention,
 * the file has the same name as the image file, with the third letter of the extension jammed with a w: tif->tfw, jpg->jqw.
 * The format is the following:
 * @code
 *    5.000000000000 (size of pixel in x direction)
 *    0.000000000000 (rotation term for row)
 *    0.000000000000 (rotation term for column)
 *    -5.000000000000 (size of pixel in y direction)
 *    492169.690845528910 (x coordinate of centre of upper left pixel in map units)
 *    5426523.318065105000 (y coordinate of centre of upper left pixel in map units)
 * @endcode
64
 *
65
 * @section example Example use
66
67
68
69
70
71
 * @code
 * GRID2D = PNG
 * png_legend = false
 * png_min_size = 400x400
 * png_max_size = 1366*768
 * @endcode
72
73
74
 */

const double PNGIO::plugin_nodata = -999.; //plugin specific nodata value. It can also be read by the plugin (depending on what is appropriate)
75
76
77
const unsigned char PNGIO::channel_depth = 8;
const unsigned char PNGIO::channel_max_color = 255;
const unsigned char PNGIO::transparent_grey = channel_max_color;
78
79
80
const bool PNGIO::indexed_png = true;
const bool PNGIO::optimize_for_speed = true;
const unsigned int PNGIO::nr_levels = 30;
81
82
83

PNGIO::PNGIO(void (*delObj)(void*), const Config& i_cfg) : IOInterface(delObj), cfg(i_cfg)
{
84
	setOptions();
85
86
87
88
}

PNGIO::PNGIO(const std::string& configfile) : IOInterface(NULL), cfg(configfile)
{
89
	setOptions();
90
91
92
93
}

PNGIO::PNGIO(const Config& cfgreader) : IOInterface(NULL), cfg(cfgreader)
{
94
95
96
97
98
	setOptions();
}

void PNGIO::setOptions()
{
99
100
	cfg.getValue("COORDSYS", "Output", coordout);
	cfg.getValue("COORDPARAM", "Output", coordoutparam, Config::nothrow);
101
	cfg.getValue("GRID2DPATH", "Output", grid2dpath);
102
103
	//cfg.getValue("TIME_ZONE", "Output", tz_out, Config::nothrow);

104
105
106
	//get size specifications
	std::string min_size, max_size;
	min_w = min_h = max_w = max_h = IOUtils::unodata;
107
	cfg.getValue("PNG_MIN_SIZE", "Output", min_size, Config::nothrow);
108
	if(min_size!="") parse_size(min_size, min_w, min_h);
109
	cfg.getValue("PNG_MAX_SIZE", "Output", max_size, Config::nothrow);
110
	if(max_size!="") parse_size(max_size, max_w, max_h);
111

112
	autoscale = true;
113
	cfg.getValue("PNG_AUTOSCALE", "Output", autoscale, Config::nothrow);
114
	has_legend = true;
115
	cfg.getValue("PNG_LEGEND", "Output", has_legend, Config::nothrow);
116
	scaling = "bilinear";
117
	cfg.getValue("PNG_SCALING", "Output", scaling, Config::nothrow);
118
	has_world_file=false;
119
	cfg.getValue("PNG_WORLD_FILE", "Output", has_world_file, Config::nothrow);
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157

	if(has_legend) { //we need to save room for the legend
		if(min_w!=IOUtils::unodata) min_w -= legend::getLegendWidth();
		if(max_w!=IOUtils::unodata) max_w -= legend::getLegendWidth();
	}
}

void PNGIO::parse_size(const std::string& size_spec, unsigned int& width, unsigned int& height)
{
	char rest[32] = "";
	if(sscanf(size_spec.c_str(), "%u %u%31s", &width, &height, rest) < 2)
	if(sscanf(size_spec.c_str(), "%u*%u%31s", &width, &height, rest) < 2)
	if(sscanf(size_spec.c_str(), "%ux%u%31s", &width, &height, rest) < 2) {
		std::stringstream ss;
		ss << "Can not parse PNGIO size specification \"" << size_spec << "\"";
		throw InvalidFormatException(ss.str(), AT);
	}
	std::string tmp(rest);
	IOUtils::trim(tmp);
	if ((tmp.length() > 0) && tmp[0] != '#' && tmp[0] != ';') {//if line holds more than one value it's invalid
		std::stringstream ss;
		ss << "Invalid PNGIO size specification \"" << size_spec << "\"";
		throw InvalidFormatException(ss.str(), AT);
	}
}

double PNGIO::getScaleFactor(const double& grid_w, const double& grid_h)
{
	if(grid_w==0 || grid_h==0) {
		return 1.;
	}

	double min_factor = IOUtils::nodata;
	if(min_w!=IOUtils::unodata) { //min_w & min_w are read together
		const double min_w_factor = (double)min_w / (double)grid_w;
		const double min_h_factor = (double)min_h / (double)grid_h;
		min_factor = std::max(min_w_factor, min_h_factor);
	}
158

159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
	double max_factor = IOUtils::nodata;
	if(max_w!=IOUtils::unodata) { //max_w & max_h are read together
		const double max_w_factor = (double)max_w / (double)grid_w;
		const double max_h_factor = (double)max_h / (double)grid_h;
		max_factor = std::min(max_w_factor, max_h_factor);
	}

	if(min_factor==IOUtils::nodata && max_factor==IOUtils::nodata)
		return 1.; //no user given specification
	if(min_factor!=IOUtils::nodata && max_factor!=IOUtils::nodata)
		return (min_factor+max_factor)/2.; //both min & max -> average

	//only one size specification provided -> return its matching factor
	if(min_factor!=IOUtils::nodata)
		return min_factor;
	else
		return max_factor;
176
177
}

178
PNGIO::~PNGIO() throw() {
179
180
181

}

182
183
184
185
186
187
188
void PNGIO::read2DGrid(Grid2DObject&, const std::string&)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::read2DGrid(Grid2DObject&, const MeteoGrids::Parameters& , const Date&)
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readDEM(DEMObject& /*dem_out*/)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readLanduse(Grid2DObject& /*landuse_out*/)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readAssimilationData(const Date& /*date_in*/, Grid2DObject& /*da_out*/)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readStationData(const Date&, std::vector<StationData>& /*vecStation*/)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readMeteoData(const Date& /*dateStart*/, const Date& /*dateEnd*/,
                             std::vector< std::vector<MeteoData> >& /*vecMeteo*/,
                             const size_t&)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::writeMeteoData(const std::vector< std::vector<MeteoData> >& /*vecMeteo*/,
                              const std::string&)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

void PNGIO::readSpecialPoints(std::vector<Coords>&)
{
	//Nothing so far
	throw IOException("Nothing implemented here", AT);
}

239
240
Grid2DObject PNGIO::scaleGrid(const Grid2DObject& grid_in)
{ //scale input image
241
	const double factor = getScaleFactor(grid_in.ncols, grid_in.nrows);
242
	if(scaling=="nearest")
243
		return ResamplingAlgorithms2D::NearestNeighbour(grid_in, factor);
244
	else if(scaling=="bilinear")
245
		return ResamplingAlgorithms2D::BilinearResampling(grid_in, factor);
246
247
248
249
250
	else {
		stringstream ss;
		ss << "Grid scaling algorithm \"" << scaling << "\" unknown";
		throw UnknownValueException(ss.str(), AT);
	}
251
}
252

253
void PNGIO::setFile(const std::string& filename, png_structp& png_ptr, png_infop& info_ptr, const unsigned int &width, const unsigned int &height)
254
{
255
256
257
258
	// Open file for writing (binary mode)
	if (!IOUtils::validFileName(filename)) {
		throw InvalidFileNameException(filename, AT);
	}
259
	errno=0;
260
261
	fp = fopen(filename.c_str(), "wb");
	if (fp == NULL) {
262
263
264
		stringstream ss;
		ss << "Error openning file \"" << filename << "\", possible reason: " << strerror(errno);
		throw FileAccessException(ss.str(), AT);
265
266
267
268
269
270
271
272
273
274
275
276
277
278
	}

	// Initialize write structure
	png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
	if (png_ptr == NULL) {
		fclose(fp);
		throw IOException("Could not allocate write structure", AT);
	}

	// Initialize info structure
	info_ptr = png_create_info_struct(png_ptr);
	if (info_ptr == NULL) {
		fclose(fp);
		png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
279
		free(png_ptr);
280
281
282
283
284
		throw IOException("Could not allocate info structure", AT);
	}

	// Setup Exception handling
	if (setjmp(png_jmpbuf(png_ptr))) {
285
286
		closePNG(png_ptr, info_ptr);
		throw IOException("Error during png creation. Can not set jump pointer (I have no clue what it means too!)", AT);
287
288
289
290
	}

	png_init_io(png_ptr, fp);

291
292
	//png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
	if(optimize_for_speed) png_set_compression_level(png_ptr, Z_BEST_SPEED);
293
294
	png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, PNG_FILTER_SUB|PNG_FILTER_UP); //any other filter is costly and brings close to nothing...
	if(indexed_png) png_set_compression_strategy(png_ptr, Z_RLE); //Z_DEFAULT_STRATEGY, Z_FILTERED, Z_HUFFMAN_ONLY, Z_RLE
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312

	// Write header (8 bit colour depth). Full alpha channel with PNG_COLOR_TYPE_RGB_ALPHA
	if(indexed_png) {
		png_set_IHDR(png_ptr, info_ptr, width, height,
			channel_depth, PNG_COLOR_TYPE_PALETTE, PNG_INTERLACE_NONE,
			PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
		//set transparent color (ie: cheap transparency: leads to smaller files and shorter run times)
		png_byte trans = 0; //by convention, the gradient define it as color 0
		png_set_tRNS(png_ptr, info_ptr, &trans, 1, 0);
	} else {
		png_set_IHDR(png_ptr, info_ptr, width, height,
			channel_depth, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
			PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
		//set transparent color (ie: cheap transparency: leads to smaller files and shorter run times)
		png_color_16 trans_rgb_value = {transparent_grey, transparent_grey, transparent_grey, transparent_grey, transparent_grey};
		png_set_tRNS(png_ptr, info_ptr, 0, 0, &trans_rgb_value);
	}

313
314
315
	//set background color to help applications show the picture when no background is present
	png_color_16 background = {channel_max_color, channel_max_color, channel_max_color, channel_max_color, channel_max_color};
	png_set_background(png_ptr, &background, PNG_BACKGROUND_GAMMA_SCREEN, true, 1.0);
316
317
318
319
}

unsigned int PNGIO::setLegend(const unsigned int &ncols, const unsigned int &nrows, const double &min, const double &max, Array2D<double> &legend_array)
{
320
321
322
323
324
	if(has_legend) {
		legend leg(nrows, min, max);
		legend_array = leg.getLegend();
		unsigned int nx, ny;
		legend_array.size(nx,ny);
325
326
327
		return (ncols+nx);
	} else {
		return ncols;
328
	}
329
330
}

331
void PNGIO::writeDataSection(const Grid2DObject &grid, const Array2D<double> &legend_array, const Gradient &gradient, const unsigned int &full_width, const png_structp &png_ptr)
332
{
333
334
	const double ncols = grid.ncols;
	const double nrows = grid.nrows;
335

336
	// Allocate memory for one row (3 bytes per pixel - RGB)
337
338
339
340
341
342
	unsigned char channels;
	if(indexed_png)
		channels = 1;
	else
		channels = 3;

343
344
345
346
	png_bytep row = (png_bytep)calloc(channels*sizeof(png_byte), full_width);
	if(row==NULL) {
		throw IOException("Can not allocate row memory in PNGIO!", AT);
	}
347
348

	// Write image data
349
350
351
352
353
354
355
356
357
358
359
360
361
362
	if(indexed_png) {
		for(int y=nrows-1 ; y>=0 ; y--) {
			unsigned int x=0;
			for(; x<ncols ; x++) {
				const unsigned int i=x*channels;
				unsigned int index;
				gradient.getColor(grid(x,y), index);
				row[i]=index;
			}
			for(; x<full_width; x++) {
				const unsigned int i=x*channels;
				unsigned int index;
				gradient.getColor(legend_array(x-ncols,y), index);
				row[i]=index;
363
			}
364
			png_write_row(png_ptr, row);
365
		}
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
	} else {
		for(int y=nrows-1 ; y>=0 ; y--) {
			unsigned int x=0;
			for(; x<ncols ; x++) {
				const unsigned int i=x*channels;
				unsigned char r,g,b;
				bool a;
				gradient.getColor(grid(x,y), r,g,b,a);
				if(a==true) {
					row[i]=transparent_grey; row[i+1]=transparent_grey; row[i+2]=transparent_grey;
				} else {
					row[i]=r; row[i+1]=g; row[i+2]=b;
				}
			}
			for(; x<full_width; x++) {
				const unsigned int i=x*channels;
				unsigned char r,g,b;
				bool a;
				gradient.getColor(legend_array(x-ncols,y), r,g,b,a);
				if(a==true) {
					row[i]=transparent_grey; row[i+1]=transparent_grey; row[i+2]=transparent_grey;
				} else {
					row[i]=r; row[i+1]=g; row[i+2]=b;
				}
390
			}
391
			png_write_row(png_ptr, row);
392
393
		}
	}
394

395
396
	png_write_flush(png_ptr);
	png_free(png_ptr, row);
397
398
}

399
400
401
402
403
404
405
406
407
408
409
410
411
412
void PNGIO::setPalette(const Gradient &gradient, png_structp& png_ptr, png_infop& info_ptr)
{
	std::vector<unsigned char> r, g, b;
	gradient.getPalette(r,g,b);
	const size_t nr_colors = r.size();
	png_color *palette = (png_color*)calloc(sizeof (png_color), nr_colors);
	for(size_t ii=0; ii<nr_colors; ii++) {
		palette[ii].red = r[ii];
		palette[ii].green = g[ii];
		palette[ii].blue = b[ii];
	}
	png_set_PLTE(png_ptr, info_ptr, palette, nr_colors);
}

413
void PNGIO::closePNG(png_structp& png_ptr, png_infop& info_ptr)
414
{
415
416
	fclose(fp);
	png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
417
	if(info_ptr->palette!=NULL) free(info_ptr->palette);
418
419
420
	png_destroy_write_struct(&png_ptr, &info_ptr);
	free(info_ptr);
	free(png_ptr);
421
422
}

423
void PNGIO::write2DGrid(const Grid2DObject& grid_in, const std::string& filename)
424
{
425
	string full_name = grid2dpath+"/"+filename;
426
	fp=NULL;
427
428
429
430
431
432
433
434
435
436
	png_structp png_ptr=NULL;
	png_infop info_ptr=NULL;

	//scale input image
	const Grid2DObject grid = scaleGrid(grid_in);
	const double ncols = grid.ncols, nrows = grid.nrows;
	const double min = grid.grid2D.getMin();
	const double max = grid.grid2D.getMax();

	Gradient gradient(Gradient::heat, min, max, autoscale);
437
	gradient.setNrOfLevels(nr_levels);
438
439
440
441

	Array2D<double> legend_array; //it will remain empty if there is no legend
	const unsigned int full_width = setLegend(ncols, nrows, min, max, legend_array);

442
	setFile(full_name, png_ptr, info_ptr, full_width, nrows);
443
	if(indexed_png) setPalette(gradient, png_ptr, info_ptr);
444
	if(has_world_file) writeWorldFile(grid, full_name);
445
446
447
448
449
450
451
452

	createMetadata(grid);
	metadata_key.push_back("Title"); //adding generic title
	metadata_text.push_back("Unknown Gridded data");
	writeMetadata(png_ptr, info_ptr);

	writeDataSection(grid, legend_array, gradient, full_width, png_ptr);
	png_write_end(png_ptr, NULL);
453
454

	closePNG(png_ptr, info_ptr);
455
456
}

457
void PNGIO::write2DGrid(const Grid2DObject& grid_in, const MeteoGrids::Parameters& parameter, const Date& date)
458
{
459
460
	std::string filename;
	if(parameter==MeteoGrids::DEM || parameter==MeteoGrids::SLOPE || parameter==MeteoGrids::AZI)
461
		filename = grid2dpath + "/" + MeteoGrids::getParameterName(parameter) + ".png";
462
	else
463
		filename = grid2dpath + "/" + date.toString(Date::NUM) + "_" + MeteoGrids::getParameterName(parameter) + ".png";
464

465
	fp=NULL;
466
467
468
469
470
471
472
473
474
475
476
	png_structp png_ptr=NULL;
	png_infop info_ptr=NULL;

	//scale input image
	Grid2DObject grid = scaleGrid(grid_in);
	const double ncols = grid.ncols, nrows = grid.nrows;
	double min = grid.grid2D.getMin();
	double max = grid.grid2D.getMax();

	Gradient gradient;
	if(parameter==MeteoGrids::DEM) {
477
478
		if(!autoscale) {
			min = 0.; //we want a 3000 snow line with a full scale legend
479
480
			max = 3500.;
			gradient.set(Gradient::terrain, min, max, autoscale); //max used as snow line reference
481
482
		} else
			gradient.set(Gradient::terrain, min, max, autoscale);
483
484
485
	} else if(parameter==MeteoGrids::SLOPE) {
		gradient.set(Gradient::slope, min, max, autoscale);
	} else if(parameter==MeteoGrids::AZI) {
486
487
488
489
		if(!autoscale) {
			min = 0.;
			max = 360.;
		}
490
491
		gradient.set(Gradient::azi, min, max, autoscale);
	} else if(parameter==MeteoGrids::HS) {
492
493
494
495
		if(!autoscale) {
			min = 0.; max = 3.5;
		}
		gradient.set(Gradient::blue, min, max, autoscale);
496
497
	} else if(parameter==MeteoGrids::TA) {
		grid.grid2D -= Cst::t_water_freezing_pt; //convert to celsius
498
499
500
501
502
503
		if(!autoscale) {
			min = -10.; max = 10.;
		} else {
			min -= Cst::t_water_freezing_pt;
			max -= Cst::t_water_freezing_pt;
		}
504
		gradient.set(Gradient::heat, min, max, autoscale);
505
506
507
508
509
510
511
512
513
	} else if(parameter==MeteoGrids::TSS) {
		grid.grid2D -= Cst::t_water_freezing_pt; //convert to celsius
		if(!autoscale) {
			min = -10.; max = 10.;
		} else {
			min -= Cst::t_water_freezing_pt;
			max -= Cst::t_water_freezing_pt;
		}
		gradient.set(Gradient::freeze, min, max, autoscale);
514
	} else if(parameter==MeteoGrids::RH) {
515
516
517
		if(!autoscale) {
			min = 0.; max = 1.;
		}
518
519
520
521
522
523
		gradient.set(Gradient::bg_isomorphic, min, max, autoscale);
	} else if(parameter==MeteoGrids::ALB) {
		if(!autoscale) {
			min = 0.; max = 1.;
		}
		gradient.set(Gradient::bg_isomorphic, min, max, autoscale);
524
	} else if(parameter==MeteoGrids::SWE) {
525
526
527
528
		if(!autoscale) {
			min = 0.; max = 2000.;
		}
		gradient.set(Gradient::blue, min, max, autoscale);
529
530
531
	} else {
		gradient.set(Gradient::heat, min, max, autoscale);
	}
532
	gradient.setNrOfLevels(nr_levels);
533
534

	Array2D<double> legend_array; //it will remain empty if there is no legend
535
	const unsigned int full_width = setLegend(ncols, nrows, min, max, legend_array);
536

537
	setFile(filename, png_ptr, info_ptr, full_width, nrows);
538
	if(indexed_png) setPalette(gradient, png_ptr, info_ptr);
539
	if(has_world_file) writeWorldFile(grid, filename);
540
541
542
543

	createMetadata(grid);
	metadata_key.push_back("Title"); //adding title
	metadata_text.push_back( MeteoGrids::getParameterName(parameter)+" on "+date.toString(Date::ISO) );
544
545
	metadata_key.push_back("Simulation Date");
	metadata_text.push_back( date.toString(Date::ISO) );
546
547
	metadata_key.push_back("Simulation Parameter");
	metadata_text.push_back( MeteoGrids::getParameterName(parameter) );
548
549
550
551
	writeMetadata(png_ptr, info_ptr);

	writeDataSection(grid, legend_array, gradient, full_width, png_ptr);
	png_write_end(png_ptr, NULL);
552
553
554
555
556
557
558
559
560
561

	closePNG(png_ptr, info_ptr);
}

void PNGIO::writeWorldFile(const Grid2DObject& grid_in, const std::string& filename)
{
	const string world_file = IOUtils::removeExtension(filename)+".pnw";
	const double cellsize = grid_in.cellsize;
	Coords world_ref=grid_in.llcorner;
	world_ref.setProj(coordout, coordoutparam);
562
	world_ref.moveByXY(.5*cellsize, (grid_in.nrows+.5)*cellsize); //moving to center of upper left cell
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582

	std::ofstream fout;
	fout.open(world_file.c_str());
	if (fout.fail()) {
		throw FileAccessException(world_file, AT);
	}

	try {
		fout << std::setprecision(12) << cellsize << "\n";
		fout << "0.000000000000\n";
		fout << "0.000000000000\n";
		fout << std::setprecision(12) << -cellsize << "\n";
		fout << std::setprecision(12) << world_ref.getEasting() << "\n";
		fout << std::setprecision(12) << world_ref.getNorthing() << "\n";
	} catch(...) {
		fout.close();
		throw FileAccessException("Failed when writing to PNG world file \""+world_file+"\"", AT);
	}

	fout.close();
583
584
}

585
void PNGIO::createMetadata(const Grid2DObject& grid)
586
{
587
588
589
590
	const double lat = grid.llcorner.getLat();
	const double lon = grid.llcorner.getLon();
	stringstream ss;

591
592
593
	metadata_key.clear();
	metadata_text.clear();

594
595
596
597
	metadata_key.push_back("Creation Time");
	Date cr_date;
	cr_date.setFromSys();
	metadata_text.push_back( cr_date.toString(Date::ISO) );
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
	metadata_key.push_back("Author");
	metadata_text.push_back(IOUtils::getLogName());
	metadata_key.push_back("Software");
	metadata_text.push_back("MeteoIO "+getLibVersion());
	metadata_key.push_back("Position");
	metadata_text.push_back("llcorner");
	metadata_key.push_back("Cellsize");
	ss.str(""); ss << fixed << setprecision(2) << grid.cellsize;
	metadata_text.push_back(ss.str());
	metadata_key.push_back("Latitude");
	ss.str(""); ss << fixed << setprecision(6) << lat;
	metadata_text.push_back(ss.str());
	metadata_key.push_back("Longitude");
	ss.str(""); ss << fixed << setprecision(6) << lon;
	metadata_text.push_back(ss.str());
613

614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
	if(lat<0.) {
		metadata_key.push_back("LatitudeRef");
		metadata_text.push_back("S");
		metadata_key.push_back("GPSLatitude");
		metadata_text.push_back(decimal_to_dms(-lat));
	} else {
		metadata_key.push_back("LatitudeRef");
		metadata_text.push_back("N");
		metadata_key.push_back("GPSLatitude");
		metadata_text.push_back(decimal_to_dms(lat));
	}
	if(lon<0.) {
		metadata_key.push_back("LongitudeRef");
		metadata_text.push_back("W");
		metadata_key.push_back("GPSLongitude");
		metadata_text.push_back(decimal_to_dms(-lon));
	} else {
		metadata_key.push_back("LongitudeRef");
		metadata_text.push_back("E");
		metadata_key.push_back("GPSLongitude");
		metadata_text.push_back(decimal_to_dms(lon));
	}
}

void PNGIO::writeMetadata(png_structp &png_ptr, png_infop &info_ptr)
{
	const size_t nr = metadata_key.size();
	png_text *info_text;
	info_text = (png_text *)calloc(sizeof(png_text), nr);
	char **key, **text;
	key = (char**)calloc(sizeof(char)*80, nr);
	text = (char**)calloc(sizeof(char)*80, nr);

	for(size_t ii=0; ii<nr; ii++) {
		key[ii] = (char *)calloc(sizeof(char), 80);
		text[ii] = (char *)calloc(sizeof(char), 80);
		strncpy(key[ii], metadata_key[ii].c_str(), 80);
		strncpy(text[ii], metadata_text[ii].c_str(), 80);
		info_text[ii].key = key[ii];
		info_text[ii].text = text[ii];
		info_text[ii].compression = PNG_TEXT_COMPRESSION_NONE;
	}
656

657
	png_set_text(png_ptr, info_ptr, info_text, nr);
658
659
	png_write_info(png_ptr, info_ptr);

660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
	free(info_text);
	for(size_t ii=0; ii<nr; ii++) {
		free(key[ii]);
		free(text[ii]);
	}
	free(key);
	free(text);
}

std::string PNGIO::decimal_to_dms(const double& decimal) {
	std::stringstream dms;
	const int d = static_cast<int>( floor(decimal) );
	const double m = floor( ((decimal - (double)d)*60.)*100. ) / 100.;
	const double s = 3600.*(decimal - (double)d) - 60.*m;

	dms << d << "/1 " << static_cast<int>(m*100) << "/100 " << fixed << setprecision(6) << s << "/1";
	return dms.str();
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
}

#ifndef _METEOIO_JNI
extern "C"
{
#define COMPILE_PLUGIN
#include "exports.h"

	METEOIO_EXPORT void deleteObject(void* obj) {
		delete reinterpret_cast<PluginObject*>(obj);
	}

	METEOIO_EXPORT void* loadObject(const string& classname, const Config& cfg) {
		if(classname == "PNGIO") {
			//cerr << "Creating dynamic handle for " << classname << endl;
			return new PNGIO(deleteObject, cfg);
		}
		//cerr << "Could not load " << classname << endl;
		return NULL;
	}
}
#endif

} //namespace