C/C++的PNG图片编码和解码库：LodePNG
jopen
9年前
LodePNG是一个 PNG 格式图片的编码和解码库，尽在其中，没有任何依赖和联动zlib或libpng的要求。
它专为C（ISO C90）开发，并且具有一个C++封装，提供更方便的接口。
/* 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> /* 3 ways to decode a PNG from a file to RGBA pixel data (and 2 in-memory ways). */ //g++ lodepng.cpp example_decode.cpp -ansi -pedantic -Wall -Wextra -O3 //Example 1 //Decode from disk to raw pixels with a single function call void decodeOneStep(const char* filename) { std::vector<unsigned char> image; //the raw pixels unsigned width, height; //decode unsigned error = lodepng::decode(image, width, height, filename); //if there's an error, display it if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... } //Example 2 //Load PNG file from disk to memory first, then decode to raw pixels in memory. void decodeTwoSteps(const char* filename) { std::vector<unsigned char> png; std::vector<unsigned char> image; //the raw pixels unsigned width, height; //load and decode lodepng::load_file(png, filename); unsigned error = lodepng::decode(image, width, height, png); //if there's an error, display it if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... } //Example 3 //Load PNG file from disk using a State, normally needed for more advanced usage. void decodeWithState(const char* filename) { std::vector<unsigned char> png; std::vector<unsigned char> image; //the raw pixels unsigned width, height; lodepng::State state; //optionally customize this one lodepng::load_file(png, filename); //load the image file with given filename unsigned error = lodepng::decode(image, width, height, state, png); //if there's an error, display it if(error) std::cout << "decoder error " << error << ": "<< lodepng_error_text(error) << std::endl; //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... //State state contains extra information about the PNG such as text chunks, ... } int main(int argc, char *argv[]) { const char* filename = argc > 1 ? argv[1] : "test.png"; decodeOneStep(filename); }