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authorMatthew Hoops2014-02-27 21:27:23 -0500
committerMatthew Hoops2014-02-28 00:27:28 -0500
commit740b6e8fbdece44ae2a5295cb0549a53b6dc6ae7 (patch)
treed1f414522b8effe91dc2e4c75443ca18a30fc0ef /image/png.cpp
parentcbf085287c74e0994fb18fb0830ccdb340b5b0ac (diff)
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IMAGE: Move all ImageDecoders to image/
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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+// Since we need to work with libpng here, we need to allow all symbols
+// to avoid compilation issues.
+#define FORBIDDEN_SYMBOL_ALLOW_ALL
+#include "common/scummsys.h"
+
+#ifdef USE_PNG
+#include <png.h>
+#endif
+
+#include "image/png.h"
+
+#include "graphics/pixelformat.h"
+#include "graphics/surface.h"
+
+#include "common/stream.h"
+
+namespace Image {
+
+PNGDecoder::PNGDecoder() : _outputSurface(0), _palette(0), _paletteColorCount(0), _stream(0) {
+}
+
+PNGDecoder::~PNGDecoder() {
+ destroy();
+}
+
+void PNGDecoder::destroy() {
+ if (_outputSurface) {
+ _outputSurface->free();
+ delete _outputSurface;
+ _outputSurface = 0;
+ }
+ delete[] _palette;
+ _palette = NULL;
+}
+
+#ifdef USE_PNG
+// libpng-error-handling:
+void pngError(png_structp pngptr, png_const_charp errorMsg) {
+ error("%s", errorMsg);
+}
+
+void pngWarning(png_structp pngptr, png_const_charp warningMsg) {
+ warning("%s", warningMsg);
+}
+
+// libpng-I/O-helper:
+void pngReadFromStream(png_structp pngPtr, png_bytep data, png_size_t length) {
+ void *readIOptr = png_get_io_ptr(pngPtr);
+ Common::SeekableReadStream *stream = (Common::SeekableReadStream *)readIOptr;
+ stream->read(data, length);
+}
+#endif
+
+/*
+ * This code is based on Broken Sword 2.5 engine
+ *
+ * Copyright (c) Malte Thiesen, Daniel Queteschiner and Michael Elsdoerfer
+ *
+ * Licensed under GNU GPL v2
+ *
+ */
+
+bool PNGDecoder::loadStream(Common::SeekableReadStream &stream) {
+#ifdef USE_PNG
+ destroy();
+
+ _stream = &stream;
+
+ // First, check the PNG signature
+ if (_stream->readUint32BE() != MKTAG(0x89, 'P', 'N', 'G')) {
+ delete _stream;
+ return false;
+ }
+ if (_stream->readUint32BE() != MKTAG(0x0d, 0x0a, 0x1a, 0x0a)) {
+ delete _stream;
+ return false;
+ }
+
+ // The following is based on the guide provided in:
+ //http://www.libpng.org/pub/png/libpng-1.2.5-manual.html#section-3
+ //http://www.libpng.org/pub/png/libpng-1.4.0-manual.pdf
+ // along with the png-loading code used in the sword25-engine.
+ png_structp pngPtr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+ if (!pngPtr) {
+ delete _stream;
+ return false;
+ }
+ png_infop infoPtr = png_create_info_struct(pngPtr);
+ if (!infoPtr) {
+ png_destroy_read_struct(&pngPtr, NULL, NULL);
+ delete _stream;
+ return false;
+ }
+ png_infop endInfo = png_create_info_struct(pngPtr);
+ if (!endInfo) {
+ png_destroy_read_struct(&pngPtr, &infoPtr, NULL);
+ delete _stream;
+ return false;
+ }
+
+ png_set_error_fn(pngPtr, NULL, pngError, pngWarning);
+ // TODO: The manual says errors should be handled via setjmp
+
+ png_set_read_fn(pngPtr, _stream, pngReadFromStream);
+ png_set_crc_action(pngPtr, PNG_CRC_DEFAULT, PNG_CRC_WARN_USE);
+ // We already verified the PNG-header
+ png_set_sig_bytes(pngPtr, 8);
+
+ // Read PNG header
+ png_read_info(pngPtr, infoPtr);
+
+ // No handling for unknown chunks yet.
+ int bitDepth, colorType, width, height, interlaceType;
+ png_uint_32 w, h;
+ png_get_IHDR(pngPtr, infoPtr, &w, &h, &bitDepth, &colorType, &interlaceType, NULL, NULL);
+ width = w;
+ height = h;
+
+ // Allocate memory for the final image data.
+ // To keep memory framentation low this happens before allocating memory for temporary image data.
+ _outputSurface = new Graphics::Surface();
+
+ // Images of all color formats except PNG_COLOR_TYPE_PALETTE
+ // will be transformed into ARGB images
+ if (colorType == PNG_COLOR_TYPE_PALETTE && !png_get_valid(pngPtr, infoPtr, PNG_INFO_tRNS)) {
+ int numPalette = 0;
+ png_colorp palette = NULL;
+ uint32 success = png_get_PLTE(pngPtr, infoPtr, &palette, &numPalette);
+ if (success != PNG_INFO_PLTE) {
+ png_destroy_read_struct(&pngPtr, &infoPtr, NULL);
+ return false;
+ }
+ _paletteColorCount = numPalette;
+ _palette = new byte[_paletteColorCount * 3];
+ for (int i = 0; i < _paletteColorCount; i++) {
+ _palette[(i * 3)] = palette[i].red;
+ _palette[(i * 3) + 1] = palette[i].green;
+ _palette[(i * 3) + 2] = palette[i].blue;
+
+ }
+ _outputSurface->create(width, height, Graphics::PixelFormat::createFormatCLUT8());
+ png_set_packing(pngPtr);
+ } else {
+ bool isAlpha = (colorType & PNG_COLOR_MASK_ALPHA);
+ if (png_get_valid(pngPtr, infoPtr, PNG_INFO_tRNS)) {
+ isAlpha = true;
+ png_set_expand(pngPtr);
+ }
+ _outputSurface->create(width, height, Graphics::PixelFormat(4,
+ 8, 8, 8, isAlpha ? 8 : 0, 24, 16, 8, 0));
+ if (!_outputSurface->getPixels()) {
+ error("Could not allocate memory for output image.");
+ }
+ if (bitDepth == 16)
+ png_set_strip_16(pngPtr);
+ if (bitDepth < 8)
+ png_set_expand(pngPtr);
+ if (colorType == PNG_COLOR_TYPE_GRAY ||
+ colorType == PNG_COLOR_TYPE_GRAY_ALPHA)
+ png_set_gray_to_rgb(pngPtr);
+
+ // PNGs are Big-Endian:
+#ifdef SCUMM_LITTLE_ENDIAN
+ png_set_bgr(pngPtr);
+ png_set_swap_alpha(pngPtr);
+ if (colorType != PNG_COLOR_TYPE_RGB_ALPHA)
+ png_set_filler(pngPtr, 0xff, PNG_FILLER_BEFORE);
+#else
+ if (colorType != PNG_COLOR_TYPE_RGB_ALPHA)
+ png_set_filler(pngPtr, 0xff, PNG_FILLER_AFTER);
+#endif
+
+ }
+
+ // After the transformations have been registered, the image data is read again.
+ png_set_interlace_handling(pngPtr);
+ png_read_update_info(pngPtr, infoPtr);
+ png_get_IHDR(pngPtr, infoPtr, &w, &h, &bitDepth, &colorType, NULL, NULL, NULL);
+ width = w;
+ height = h;
+
+ if (interlaceType == PNG_INTERLACE_NONE) {
+ // PNGs without interlacing can simply be read row by row.
+ for (int i = 0; i < height; i++) {
+ png_read_row(pngPtr, (png_bytep)_outputSurface->getBasePtr(0, i), NULL);
+ }
+ } else {
+ // PNGs with interlacing require us to allocate an auxillary
+ // buffer with pointers to all row starts.
+
+ // Allocate row pointer buffer
+ png_bytep *rowPtr = new png_bytep[height];
+ if (!rowPtr) {
+ error("Could not allocate memory for row pointers.");
+ }
+
+ // Initialize row pointers
+ for (int i = 0; i < height; i++)
+ rowPtr[i] = (png_bytep)_outputSurface->getBasePtr(0, i);
+
+ // Read image data
+ png_read_image(pngPtr, rowPtr);
+
+ // Free row pointer buffer
+ delete[] rowPtr;
+ }
+
+ // Read additional data at the end.
+ png_read_end(pngPtr, NULL);
+
+ // Destroy libpng structures
+ png_destroy_read_struct(&pngPtr, &infoPtr, &endInfo);
+
+ // We no longer need the file stream, thus close it here
+ _stream = 0;
+
+ return true;
+#else
+ return false;
+#endif
+}
+
+} // End of namespace Image