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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 <stdio.h>
+#include <stdlib.h>
+
+/*
+3 ways to encode a PNG from RGBA pixel data to a file (and 2 in-memory ways).
+NOTE: this samples overwrite the file or test.png without warning!
+*/
+
+/*
+Example 1
+Encode from raw pixels to disk with a single function call
+The image argument has width * height RGBA pixels or width * height * 4 bytes
+*/
+void encodeOneStep(const char* filename, const unsigned char* image, unsigned width, unsigned height)
+{
+ /*Encode the image*/
+ unsigned error = lodepng_encode32_file(filename, image, width, height);
+
+ /*if there's an error, display it*/
+ if(error) printf("error %u: %s\n", error, lodepng_error_text(error));
+}
+
+/*
+Example 2
+Encode from raw pixels to an in-memory PNG file first, then write it to disk
+The image argument has width * height RGBA pixels or width * height * 4 bytes
+*/
+void encodeTwoSteps(const char* filename, const unsigned char* image, unsigned width, unsigned height)
+{
+ unsigned char* png;
+ size_t pngsize;
+
+ unsigned error = lodepng_encode32(&png, &pngsize, image, width, height);
+ if(!error) lodepng_save_file(png, pngsize, filename);
+
+ /*if there's an error, display it*/
+ if(error) printf("error %u: %s\n", error, lodepng_error_text(error));
+
+ free(png);
+}
+
+/*
+Example 3
+Save a PNG file to disk using a State, normally needed for more advanced usage.
+The image argument has width * height RGBA pixels or width * height * 4 bytes
+*/
+void encodeWithState(const char* filename, const unsigned char* image, unsigned width, unsigned height)
+{
+ unsigned error;
+ unsigned char* png;
+ size_t pngsize;
+ LodePNGState state;
+
+ lodepng_state_init(&state);
+ /*optionally customize the state*/
+
+ error = lodepng_encode(&png, &pngsize, image, width, height, &state);
+ if(!error) lodepng_save_file(png, pngsize, filename);
+
+ /*if there's an error, display it*/
+ if(error) printf("error %u: %s\n", error, lodepng_error_text(error));
+
+ lodepng_state_cleanup(&state);
+ free(png);
+}
+
+int main(int argc, char *argv[])
+{
+ const char* filename = argc > 1 ? argv[1] : "test.png";
+
+ /*generate some image*/
+ unsigned width = 512, height = 512;
+ unsigned char* image = malloc(width * height * 4);
+ unsigned x, y;
+ for(y = 0; y < height; y++)
+ for(x = 0; x < width; x++)
+ {
+ image[4 * width * y + 4 * x + 0] = 255 * !(x & y);
+ image[4 * width * y + 4 * x + 1] = x ^ y;
+ image[4 * width * y + 4 * x + 2] = x | y;
+ image[4 * width * y + 4 * x + 3] = 255;
+ }
+
+ /*run an example*/
+ encodeOneStep(filename, image, width, height);
+
+ free(image);
+ return 0;
+}