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diff --git a/example_gzip.cpp b/example_gzip.cpp
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+/*
+LodePNG Examples
+
+Copyright (c) 2005-2012 Lode Vandevenne
+
+This software is provided 'as-is', without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+    1. The origin of this software must not be misrepresented; you must not
+    claim that you wrote the original software. If you use this software
+    in a product, an acknowledgment in the product documentation would be
+    appreciated but is not required.
+
+    2. Altered source versions must be plainly marked as such, and must not be
+    misrepresented as being the original software.
+
+    3. This notice may not be removed or altered from any source
+    distribution.
+*/
+
+#include "lodepng.h"
+#include <iostream>
+#include <stdlib.h>
+
+/*
+Encodes given file as a gzip file.
+
+See also the gzip specification, RFC 1952: http://www.gzip.org/zlib/rfc-gzip.html
+*/
+
+//g++ lodepng.cpp example_gzip.cpp -ansi -pedantic -Wall -Wextra -O3
+
+//saves image to filename given as argument. Warning, this overwrites the file without warning!
+int main(int argc, char *argv[])
+{
+  if(argc < 2)
+  {
+    std::cout << "Please provide input filename (output is input with .gz)" << std::endl;
+    return 0;
+  }
+  
+  //NOTE: this sample will overwrite the output file without warning!
+  std::string infilename = argv[1];
+  std::string outfilename = infilename + ".gz";
+  
+  std::vector<unsigned char> in;
+  lodepng::load_file(in, infilename);
+  
+  size_t outsize = 10;
+  unsigned char* out = (unsigned char*)malloc(outsize);
+  out[0] = 31;  //ID1
+  out[1] = 139; //ID2
+  out[2] = 8; //CM
+  out[3] = 0; //FLG
+  //MTIME
+  out[4] = 0;
+  out[5] = 0;
+  out[6] = 0;
+  out[7] = 0;
+
+  out[8] = 2; //2 = slow, 4 = fast compression
+  out[9] = 255; //OS unknown
+  
+  lodepng_deflate(&out, &outsize, &in[0], in.size(), &lodepng_default_compress_settings);
+  
+  unsigned crc = lodepng_crc32(&in[0], in.size());
+  
+  size_t footer = outsize;
+  
+  outsize += 8;
+  out = (unsigned char*)realloc(out, outsize);
+  
+  //CRC
+  out[footer + 0] = crc % 256;
+  out[footer + 1] = (crc >> 8) % 256;
+  out[footer + 2] = (crc >> 16) % 256;
+  out[footer + 3] = (crc >> 24) % 256;
+
+  //ISIZE
+  out[footer + 4] = in.size() % 256;
+  out[footer + 5] = (in.size() >> 8) % 256;
+  out[footer + 6] = (in.size() >> 16) % 256;
+  out[footer + 7] = (in.size() >> 24) % 256;
+  
+  lodepng_save_file(out, outsize, outfilename.c_str());
+  
+  free(out);
+}