Squashed 'third_party/cimg/' content from commit 4b66369
Change-Id: I7454d9107a08dba899fd4659731733049165ae0a
git-subtree-dir: third_party/cimg
git-subtree-split: 4b66369ab4e34a46119d6c43e9adce061bb40f4b
diff --git a/examples/use_jpeg_buffer.cpp b/examples/use_jpeg_buffer.cpp
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+/*
+ #
+ # File : use_jpeg_buffer.cpp
+ # ( C++ source file )
+ #
+ # Description : Example of use for the CImg plugin 'plugins/jpeg_buffer.h'.
+ # This file is a part of the CImg Library project.
+ # ( http://cimg.eu )
+ #
+ # Copyright : Paolo Prete
+ # ( p4olo_prete(at)yahoo.it )
+ #
+ # License : CeCILL v2.0
+ # ( http://www.cecill.info/licences/Licence_CeCILL_V2-en.html )
+ #
+ # This software is governed by the CeCILL license under French law and
+ # abiding by the rules of distribution of free software. You can use,
+ # modify and/ or redistribute the software under the terms of the CeCILL
+ # license as circulated by CEA, CNRS and INRIA at the following URL
+ # "http://www.cecill.info".
+ #
+ # As a counterpart to the access to the source code and rights to copy,
+ # modify and redistribute granted by the license, users are provided only
+ # with a limited warranty and the software's author, the holder of the
+ # economic rights, and the successive licensors have only limited
+ # liability.
+ #
+ # In this respect, the user's attention is drawn to the risks associated
+ # with loading, using, modifying and/or developing or reproducing the
+ # software by the user in light of its specific status of free software,
+ # that may mean that it is complicated to manipulate, and that also
+ # therefore means that it is reserved for developers and experienced
+ # professionals having in-depth computer knowledge. Users are therefore
+ # encouraged to load and test the software's suitability as regards their
+ # requirements in conditions enabling the security of their systems and/or
+ # data to be ensured and, more generally, to use and operate it in the
+ # same conditions as regards security.
+ #
+ # The fact that you are presently reading this means that you have had
+ # knowledge of the CeCILL license and that you accept its terms.
+ #
+*/
+
+// These includes are necessary to get the plug-in compile !
+#include <cstdio>
+#include <jpeglib.h>
+#include <jerror.h>
+
+// Define plugin and include the CImg Library.
+#define cimg_plugin "plugins/jpeg_buffer.h"
+#include "CImg.h"
+using namespace cimg_library;
+
+// Main procedure
+//----------------
+int main() {
+
+ // Create a jpeg memory buffer from the content of a jpeg file.
+ // (this is for testing purposes only)
+ const char *filename_input = "foo.jpg";
+ std::fprintf(stderr," - Reading file '%s'\n",filename_input);
+ std::FILE *file_input = std::fopen(filename_input,"rb");
+ if (!file_input) { std::fprintf(stderr,"Input JPEG file not found !"); std::exit(0); }
+
+ std::fprintf(stderr," - Construct input JPEG-coded buffer\n");
+ unsigned buf_size = 500000; // Put the file size here !
+ JOCTET *buffer_input = new JOCTET[buf_size];
+ if (std::fread(buffer_input,sizeof(JOCTET),buf_size,file_input)) std::fclose(file_input);
+ // -> 'buffer_input' is now a valid jpeg-coded memory buffer.
+
+ // Create a CImg instance from the jpeg-coded buffer using the plug-in function.
+ std::fprintf(stderr," - Create CImg instance from JPEG-coded buffer\n");
+ CImg<unsigned char> img;
+ img.load_jpeg_buffer(buffer_input, buf_size);
+ delete[] buffer_input;
+
+ // Do you image processing stuff here ....
+ // Here, we just mirror the image and write "hello".
+ std::fprintf(stderr," - Do simple processing\n");
+ const unsigned char purple[] = { 255, 0, 0 };
+ const unsigned char black[] = { 0, 0, 0 };
+ img.mirror('y').draw_text(0,0," Hello! ",purple,black,1,57);
+
+ // Display image to see if everything's fine.
+ img.display("Using 'jpeg_buffer.h' plugin");
+
+ // Define a new JOCTET array where the processed image has to be saved
+ // (we don't know its dimension before compressing it, therefore we have to allocate enough memory )
+ std::fprintf(stderr," - Construct output JPEG-coded buffer\n");
+ JOCTET *buffer_output = new JOCTET[2*buf_size];
+
+ // Save processed image into this JOCTET buffer, compressed as jpeg.
+ // This is done again by using the plug-in function.
+ img.save_jpeg_buffer(buffer_output,buf_size,60);
+ // Note that here, the variable 'buf_size' contains the length of the
+ // data which have been written in the given output buffer.
+
+ // Copy the content of the above array into a new file
+ // (it should give you a valid JPEG file then !)
+ const char *filename_output = "foo_output.jpg";
+ std::fprintf(stderr," - Save output file '%s'\n",filename_output);
+ std::FILE* file_output = std::fopen(filename_output,"wb");
+ std::fwrite(buffer_output, sizeof(JOCTET), buf_size, file_output);
+ std::fclose(file_output);
+ delete[] buffer_output;
+
+ std::fprintf(stderr," - All done !\n");
+ return 0;
+}