Copy irrlichtmt to <root>/irr/

irr/src/CImageLoaderJPG.cpp

@@ -0,0 +1,263 @@
+// Copyright (C) 2002-2012 Nikolaus Gebhardt
+// This file is part of the "Irrlicht Engine".
+// For conditions of distribution and use, see copyright notice in irrlicht.h
+
+#include "CImageLoaderJPG.h"
+
+#include "IReadFile.h"
+#include "CImage.h"
+#include "os.h"
+#include "irrString.h"
+
+namespace irr
+{
+namespace video
+{
+
+//! constructor
+CImageLoaderJPG::CImageLoaderJPG()
+{
+#ifdef _DEBUG
+	setDebugName("CImageLoaderJPG");
+#endif
+}
+
+//! destructor
+CImageLoaderJPG::~CImageLoaderJPG()
+{
+}
+
+//! returns true if the file maybe is able to be loaded by this class
+//! based on the file extension (e.g. ".tga")
+bool CImageLoaderJPG::isALoadableFileExtension(const io::path &filename) const
+{
+	return core::hasFileExtension(filename, "jpg", "jpeg");
+}
+
+// struct for handling jpeg errors
+struct irr_jpeg_error_mgr
+{
+	// public jpeg error fields
+	struct jpeg_error_mgr pub;
+
+	// for longjmp, to return to caller on a fatal error
+	jmp_buf setjmp_buffer;
+
+	// for having access to the filename when printing the error messages
+	core::stringc *filename;
+};
+
+void CImageLoaderJPG::init_source(j_decompress_ptr cinfo)
+{
+	// DO NOTHING
+}
+
+boolean CImageLoaderJPG::fill_input_buffer(j_decompress_ptr cinfo)
+{
+	// DO NOTHING
+	return TRUE;
+}
+
+void CImageLoaderJPG::skip_input_data(j_decompress_ptr cinfo, long count)
+{
+	jpeg_source_mgr *src = cinfo->src;
+	if (count > 0) {
+		src->bytes_in_buffer -= count;
+		src->next_input_byte += count;
+	}
+}
+
+void CImageLoaderJPG::term_source(j_decompress_ptr cinfo)
+{
+	// DO NOTHING
+}
+
+void CImageLoaderJPG::error_exit(j_common_ptr cinfo)
+{
+	// unfortunately we need to use a goto rather than throwing an exception
+	// as gcc crashes under linux crashes when using throw from within
+	// extern c code
+
+	// Always display the message
+	(*cinfo->err->output_message)(cinfo);
+
+	// cinfo->err really points to a irr_error_mgr struct
+	irr_jpeg_error_mgr *myerr = (irr_jpeg_error_mgr *)cinfo->err;
+
+	longjmp(myerr->setjmp_buffer, 1);
+}
+
+void CImageLoaderJPG::output_message(j_common_ptr cinfo)
+{
+	// display the error message.
+	c8 temp1[JMSG_LENGTH_MAX];
+	(*cinfo->err->format_message)(cinfo, temp1);
+	core::stringc errMsg("JPEG FATAL ERROR in ");
+
+	irr_jpeg_error_mgr *myerr = (irr_jpeg_error_mgr *)cinfo->err;
+	errMsg += *myerr->filename;
+	os::Printer::log(errMsg.c_str(), temp1, ELL_ERROR);
+}
+
+//! returns true if the file maybe is able to be loaded by this class
+bool CImageLoaderJPG::isALoadableFileFormat(io::IReadFile *file) const
+{
+	if (!(file && file->seek(0)))
+		return false;
+	unsigned char header[3];
+	size_t headerLen = file->read(header, sizeof(header));
+	return headerLen >= 3 && !memcmp(header, "\xFF\xD8\xFF", 3);
+}
+
+//! creates a surface from the file
+IImage *CImageLoaderJPG::loadImage(io::IReadFile *file) const
+{
+	if (!file)
+		return 0;
+
+	core::stringc filename = file->getFileName();
+
+	u8 **rowPtr = 0;
+	u8 *input = new u8[file->getSize()];
+	file->read(input, file->getSize());
+
+	// allocate and initialize JPEG decompression object
+	struct jpeg_decompress_struct cinfo;
+	struct irr_jpeg_error_mgr jerr;
+
+	// We have to set up the error handler first, in case the initialization
+	// step fails.  (Unlikely, but it could happen if you are out of memory.)
+	// This routine fills in the contents of struct jerr, and returns jerr's
+	// address which we place into the link field in cinfo.
+
+	cinfo.err = jpeg_std_error(&jerr.pub);
+	cinfo.err->error_exit = error_exit;
+	cinfo.err->output_message = output_message;
+	jerr.filename = &filename;
+
+	// compatibility fudge:
+	// we need to use setjmp/longjmp for error handling as gcc-linux
+	// crashes when throwing within external c code
+	if (setjmp(jerr.setjmp_buffer)) {
+		// If we get here, the JPEG code has signaled an error.
+		// We need to clean up the JPEG object and return.
+
+		jpeg_destroy_decompress(&cinfo);
+
+		delete[] input;
+		delete[] rowPtr;
+
+		// return null pointer
+		return 0;
+	}
+
+	// Now we can initialize the JPEG decompression object.
+	jpeg_create_decompress(&cinfo);
+
+	// specify data source
+	jpeg_source_mgr jsrc;
+
+	// Set up data pointer
+	jsrc.bytes_in_buffer = file->getSize();
+	jsrc.next_input_byte = (JOCTET *)input;
+	cinfo.src = &jsrc;
+
+	jsrc.init_source = init_source;
+	jsrc.fill_input_buffer = fill_input_buffer;
+	jsrc.skip_input_data = skip_input_data;
+	jsrc.resync_to_restart = jpeg_resync_to_restart;
+	jsrc.term_source = term_source;
+
+	// Decodes JPG input from whatever source
+	// Does everything AFTER jpeg_create_decompress
+	// and BEFORE jpeg_destroy_decompress
+	// Caller is responsible for arranging these + setting up cinfo
+
+	// read file parameters with jpeg_read_header()
+	jpeg_read_header(&cinfo, TRUE);
+
+	bool useCMYK = false;
+	if (cinfo.jpeg_color_space == JCS_CMYK) {
+		cinfo.out_color_space = JCS_CMYK;
+		cinfo.out_color_components = 4;
+		useCMYK = true;
+	} else {
+		cinfo.out_color_space = JCS_RGB;
+		cinfo.out_color_components = 3;
+	}
+	cinfo.output_gamma = 2.2;
+	cinfo.do_fancy_upsampling = FALSE;
+
+	// reject unreasonable sizes
+	if (!checkImageDimensions(cinfo.image_width, cinfo.image_height))
+		longjmp(jerr.setjmp_buffer, 1);
+
+	// Start decompressor
+	jpeg_start_decompress(&cinfo);
+
+	// Get image data
+	u32 rowspan = cinfo.image_width * cinfo.out_color_components;
+	u32 width = cinfo.image_width;
+	u32 height = cinfo.image_height;
+
+	// Allocate memory for buffer
+	u8 *output = new u8[rowspan * height];
+
+	// Here we use the library's state variable cinfo.output_scanline as the
+	// loop counter, so that we don't have to keep track ourselves.
+	// Create array of row pointers for lib
+	rowPtr = new u8 *[height];
+
+	for (u32 i = 0; i < height; i++)
+		rowPtr[i] = &output[i * rowspan];
+
+	u32 rowsRead = 0;
+
+	while (cinfo.output_scanline < cinfo.output_height)
+		rowsRead += jpeg_read_scanlines(&cinfo, &rowPtr[rowsRead], cinfo.output_height - rowsRead);
+
+	delete[] rowPtr;
+	// Finish decompression
+
+	jpeg_finish_decompress(&cinfo);
+
+	// Release JPEG decompression object
+	// This is an important step since it will release a good deal of memory.
+	jpeg_destroy_decompress(&cinfo);
+
+	// convert image
+	IImage *image = 0;
+	if (useCMYK) {
+		image = new CImage(ECF_R8G8B8,
+				core::dimension2d<u32>(width, height));
+		const u32 size = 3 * width * height;
+		u8 *data = (u8 *)image->getData();
+		if (data) {
+			for (u32 i = 0, j = 0; i < size; i += 3, j += 4) {
+				// Also works without K, but has more contrast with K multiplied in
+				//				data[i+0] = output[j+2];
+				//				data[i+1] = output[j+1];
+				//				data[i+2] = output[j+0];
+				data[i + 0] = (char)(output[j + 2] * (output[j + 3] / 255.f));
+				data[i + 1] = (char)(output[j + 1] * (output[j + 3] / 255.f));
+				data[i + 2] = (char)(output[j + 0] * (output[j + 3] / 255.f));
+			}
+		}
+		delete[] output;
+	} else
+		image = new CImage(ECF_R8G8B8,
+				core::dimension2d<u32>(width, height), output);
+
+	delete[] input;
+
+	return image;
+}
+
+//! creates a loader which is able to load jpeg images
+IImageLoader *createImageLoaderJPG()
+{
+	return new CImageLoaderJPG();
+}
+
+} // end namespace video
+} // end namespace irr