Add ktx

ktx/external/lodepng/examples/example_reencode.cpp

@@ -0,0 +1,72 @@
+/*
+LodePNG Examples
+
+Copyright (c) 2005-2010 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.
+*/
+
+/*
+LodePNG decode-encode: decodes the image, then encodes it again, with all the
+same information, chunks, color types, etc... as the original image had.
+This sample shows how LodePNG can be used for a conforming PNG editor.
+*/
+
+//g++ lodepng.cpp example_reencode.cpp -ansi -pedantic -Wall -Wextra -lSDL -O3 -o reencode
+
+#include "lodepng.h"
+
+#include <iostream>
+
+int main(int argc, char *argv[]) {
+  std::vector<unsigned char> image;
+  unsigned w, h;
+  std::vector<unsigned char> buffer;
+  lodepng::State state;
+  unsigned error;
+
+  //check if user gave a filename
+  if(argc < 3) {
+    std::cout << "please provide in and out filename" << std::endl;
+    return 0;
+  }
+
+  state.decoder.color_convert = 0;
+  state.decoder.remember_unknown_chunks = 1; //make it reproduce even unknown chunks in the saved image
+
+  lodepng::load_file(buffer, argv[1]);
+  error = lodepng::decode(image, w, h, state, buffer);
+  if(error) {
+    std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl;
+    return 0;
+  }
+
+  buffer.clear();
+
+  state.encoder.text_compression = 1;
+
+  error = lodepng::encode(buffer, image, w, h, state);
+  if(error) {
+    std::cout << "encoder error " << error << ": " << lodepng_error_text(error) << std::endl;
+    return 0;
+  }
+
+  lodepng::save_file(buffer, argv[2]);
+}