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Tip of the day: git grep -w PI
735 lines
19 KiB
C++
735 lines
19 KiB
C++
/* ScummVM - Graphic Adventure Engine
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*
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* ScummVM is the legal property of its developers, whose names
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* are too numerous to list here. Please refer to the COPYRIGHT
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* file distributed with this source distribution.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*
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* $URL$
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* $Id$
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*
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*/
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#include "graphics/conversion.h"
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#include "graphics/jpeg.h"
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#include "graphics/pixelformat.h"
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#include "common/endian.h"
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#include "common/util.h"
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#include "common/stream.h"
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namespace Graphics {
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// Order used to traverse the quantization tables
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static const uint8 _zigZagOrder[64] = {
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0, 1, 8, 16, 9, 2, 3, 10,
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17, 24, 32, 25, 18, 11, 4, 5,
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12, 19, 26, 33, 40, 48, 41, 34,
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27, 20, 13, 6, 7, 14, 21, 28,
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35, 42, 49, 56, 57, 50, 43, 36,
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29, 22, 15, 23, 30, 37, 44, 51,
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58, 59, 52, 45, 38, 31, 39, 46,
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53, 60, 61, 54, 47, 55, 62, 63
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};
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// IDCT table built with :
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// _idct8x8[x][y] = cos(((2 * x + 1) * y) * (M_PI / 16.0)) * 0.5;
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// _idct8x8[x][y] /= sqrt(2.0) if y == 0
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static const double _idct8x8[8][8] = {
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{ 0.353553390593274, 0.490392640201615, 0.461939766255643, 0.415734806151273, 0.353553390593274, 0.277785116509801, 0.191341716182545, 0.097545161008064 },
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{ 0.353553390593274, 0.415734806151273, 0.191341716182545, -0.097545161008064, -0.353553390593274, -0.490392640201615, -0.461939766255643, -0.277785116509801 },
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{ 0.353553390593274, 0.277785116509801, -0.191341716182545, -0.490392640201615, -0.353553390593274, 0.097545161008064, 0.461939766255643, 0.415734806151273 },
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{ 0.353553390593274, 0.097545161008064, -0.461939766255643, -0.277785116509801, 0.353553390593274, 0.415734806151273, -0.191341716182545, -0.490392640201615 },
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{ 0.353553390593274, -0.097545161008064, -0.461939766255643, 0.277785116509801, 0.353553390593274, -0.415734806151273, -0.191341716182545, 0.490392640201615 },
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{ 0.353553390593274, -0.277785116509801, -0.191341716182545, 0.490392640201615, -0.353553390593273, -0.097545161008064, 0.461939766255643, -0.415734806151273 },
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{ 0.353553390593274, -0.415734806151273, 0.191341716182545, 0.097545161008064, -0.353553390593274, 0.490392640201615, -0.461939766255643, 0.277785116509801 },
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{ 0.353553390593274, -0.490392640201615, 0.461939766255643, -0.415734806151273, 0.353553390593273, -0.277785116509801, 0.191341716182545, -0.097545161008064 }
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};
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JPEG::JPEG() :
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_stream(NULL), _w(0), _h(0), _numComp(0), _components(NULL), _numScanComp(0),
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_scanComp(NULL), _currentComp(NULL) {
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// Initialize the quantization tables
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for (int i = 0; i < JPEG_MAX_QUANT_TABLES; i++)
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_quant[i] = NULL;
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// Initialize the Huffman tables
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for (int i = 0; i < 2 * JPEG_MAX_HUFF_TABLES; i++) {
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_huff[i].count = 0;
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_huff[i].values = NULL;
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_huff[i].sizes = NULL;
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_huff[i].codes = NULL;
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}
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}
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JPEG::~JPEG() {
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reset();
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}
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Surface *JPEG::getSurface(const PixelFormat &format) {
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// Make sure we have loaded data
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if (!isLoaded())
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return 0;
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// Only accept >8bpp surfaces
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if (format.bytesPerPixel == 1)
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return 0;
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// Get our component surfaces
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Graphics::Surface *yComponent = getComponent(1);
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Graphics::Surface *uComponent = getComponent(2);
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Graphics::Surface *vComponent = getComponent(3);
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Graphics::Surface *output = new Graphics::Surface();
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output->create(yComponent->w, yComponent->h, format.bytesPerPixel);
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for (uint16 i = 0; i < output->h; i++) {
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for (uint16 j = 0; j < output->w; j++) {
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byte r = 0, g = 0, b = 0;
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YUV2RGB(*((byte *)yComponent->getBasePtr(j, i)), *((byte *)uComponent->getBasePtr(j, i)), *((byte *)vComponent->getBasePtr(j, i)), r, g, b);
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if (format.bytesPerPixel == 2)
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*((uint16 *)output->getBasePtr(j, i)) = format.RGBToColor(r, g, b);
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else
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*((uint32 *)output->getBasePtr(j, i)) = format.RGBToColor(r, g, b);
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}
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}
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return output;
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}
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void JPEG::reset() {
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// Reset member variables
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_stream = NULL;
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_w = _h = 0;
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// Free the components
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for (int c = 0; c < _numComp; c++)
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_components[c].surface.free();
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delete[] _components; _components = NULL;
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_numComp = 0;
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// Free the scan components
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delete[] _scanComp; _scanComp = NULL;
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_numScanComp = 0;
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_currentComp = NULL;
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// Free the quantization tables
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for (int i = 0; i < JPEG_MAX_QUANT_TABLES; i++) {
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delete[] _quant[i];
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_quant[i] = NULL;
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}
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// Free the Huffman tables
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for (int i = 0; i < 2 * JPEG_MAX_HUFF_TABLES; i++) {
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_huff[i].count = 0;
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delete[] _huff[i].values; _huff[i].values = NULL;
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delete[] _huff[i].sizes; _huff[i].sizes = NULL;
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delete[] _huff[i].codes; _huff[i].codes = NULL;
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}
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}
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bool JPEG::read(Common::SeekableReadStream *stream) {
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// Reset member variables and tables from previous reads
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reset();
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// Save the input stream
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_stream = stream;
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bool ok = true;
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bool done = false;
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while (!_stream->eos() && ok && !done) {
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// Read the marker
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// WORKAROUND: While each and every JPEG file should end with
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// an EOI (end of image) tag, in reality this may not be the
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// case. For instance, at least one image in the Masterpiece
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// edition of Myst doesn't, yet other programs are able to read
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// the image without complaining.
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//
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// Apparently, the customary workaround is to insert a fake
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// EOI tag.
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uint16 marker = _stream->readByte();
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bool fakeEOI = false;
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if (_stream->eos()) {
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fakeEOI = true;
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marker = 0xFF;
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}
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if (marker != 0xFF) {
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error("JPEG: Invalid marker[0]: 0x%02X", marker);
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ok = false;
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break;
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}
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while (marker == 0xFF && !_stream->eos())
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marker = _stream->readByte();
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if (_stream->eos()) {
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fakeEOI = true;
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marker = 0xD9;
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}
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if (fakeEOI)
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warning("JPEG: Inserted fake EOI");
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// Process the marker data
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switch (marker) {
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case 0xC0: // Start Of Frame
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ok = readSOF0();
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break;
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case 0xC4: // Define Huffman Tables
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ok = readDHT();
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break;
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case 0xD8: // Start Of Image
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break;
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case 0xD9: // End Of Image
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done = true;
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break;
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case 0xDA: // Start Of Scan
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ok = readSOS();
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break;
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case 0xDB: // Define Quantization Tables
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ok = readDQT();
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break;
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case 0xE0: // JFIF/JFXX segment
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ok = readJFIF();
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break;
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case 0xFE: // Comment
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_stream->seek(_stream->readUint16BE() - 2, SEEK_CUR);
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break;
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default: { // Unknown marker
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uint16 size = _stream->readUint16BE();
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warning("JPEG: Unknown marker %02X, skipping %d bytes", marker, size - 2);
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_stream->seek(size - 2, SEEK_CUR);
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}
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}
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}
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return ok;
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}
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bool JPEG::readJFIF() {
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uint16 length = _stream->readUint16BE();
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uint32 tag = _stream->readUint32BE();
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if (tag != MKID_BE('JFIF')) {
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warning("JPEG::readJFIF() tag mismatch");
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return false;
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}
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if (_stream->readByte() != 0) { // NULL
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warning("JPEG::readJFIF() NULL mismatch");
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return false;
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}
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byte majorVersion = _stream->readByte();
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byte minorVersion = _stream->readByte();
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if(majorVersion != 1 || minorVersion != 1)
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warning("JPEG::readJFIF() Non-v1.1 JPEGs may not be handled correctly");
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/* byte densityUnits = */ _stream->readByte();
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/* uint16 xDensity = */ _stream->readUint16BE();
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/* uint16 yDensity = */ _stream->readUint16BE();
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byte thumbW = _stream->readByte();
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byte thumbH = _stream->readByte();
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_stream->seek(thumbW * thumbH * 3, SEEK_CUR); // Ignore thumbnail
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if (length != (thumbW * thumbH * 3) + 16) {
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warning("JPEG::readJFIF() length mismatch");
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return false;
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}
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return true;
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}
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// Marker 0xC0 (Start Of Frame, Baseline DCT)
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bool JPEG::readSOF0() {
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debug(5, "JPEG: readSOF0");
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uint16 size = _stream->readUint16BE();
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// Read the sample precision
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uint8 precision = _stream->readByte();
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if (precision != 8) {
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warning("JPEG: Just 8 bit precision supported at the moment");
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return false;
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}
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// Image size
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_h = _stream->readUint16BE();
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_w = _stream->readUint16BE();
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// Number of components
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_numComp = _stream->readByte();
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if (size != 8 + 3 * _numComp) {
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warning("JPEG: Invalid number of components");
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return false;
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}
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// Allocate the new components
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delete[] _components;
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_components = new Component[_numComp];
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// Read the components details
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for (int c = 0; c < _numComp; c++) {
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_components[c].id = _stream->readByte();
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_components[c].factorH = _stream->readByte();
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_components[c].factorV = _components[c].factorH & 0xF;
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_components[c].factorH >>= 4;
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_components[c].quantTableSelector = _stream->readByte();
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}
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return true;
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}
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// Marker 0xC4 (Define Huffman Tables)
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bool JPEG::readDHT() {
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debug(5, "JPEG: readDHT");
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uint16 size = _stream->readUint16BE() - 2;
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uint32 pos = _stream->pos();
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while ((uint32)_stream->pos() < (size + pos)) {
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// Read the table type and id
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uint8 tableId = _stream->readByte();
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uint8 tableType = tableId >> 4; // type 0: DC, 1: AC
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tableId &= 0xF;
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uint8 tableNum = (tableId << 1) + tableType;
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// Free the Huffman table
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delete[] _huff[tableNum].values; _huff[tableNum].values = NULL;
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delete[] _huff[tableNum].sizes; _huff[tableNum].sizes = NULL;
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delete[] _huff[tableNum].codes; _huff[tableNum].codes = NULL;
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// Read the number of values for each length
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uint8 numValues[16];
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_huff[tableNum].count = 0;
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for (int len = 0; len < 16; len++) {
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numValues[len] = _stream->readByte();
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_huff[tableNum].count += numValues[len];
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}
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// Allocate memory for the current table
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_huff[tableNum].values = new uint8[_huff[tableNum].count];
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_huff[tableNum].sizes = new uint8[_huff[tableNum].count];
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_huff[tableNum].codes = new uint16[_huff[tableNum].count];
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// Read the table contents
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int cur = 0;
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for (int len = 0; len < 16; len++) {
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for (int i = 0; i < numValues[len]; i++) {
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_huff[tableNum].values[cur] = _stream->readByte();
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_huff[tableNum].sizes[cur] = len + 1;
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cur++;
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}
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}
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// Fill the table of Huffman codes
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cur = 0;
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uint16 curCode = 0;
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uint8 curCodeSize = _huff[tableNum].sizes[0];
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while (cur < _huff[tableNum].count) {
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// Increase the code size to fit the request
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while (_huff[tableNum].sizes[cur] != curCodeSize) {
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curCode <<= 1;
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curCodeSize++;
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}
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// Assign the current code
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_huff[tableNum].codes[cur] = curCode;
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curCode++;
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cur++;
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}
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}
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return true;
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}
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// Marker 0xDA (Start Of Scan)
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bool JPEG::readSOS() {
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debug(5, "JPEG: readSOS");
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uint16 size = _stream->readUint16BE();
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// Number of scan components
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_numScanComp = _stream->readByte();
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if (size != 6 + 2 * _numScanComp) {
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warning("JPEG: Invalid number of components");
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return false;
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}
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// Allocate the new scan components
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delete[] _scanComp;
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_scanComp = new Component *[_numScanComp];
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// Reset the maximum sampling factors
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_maxFactorV = 0;
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_maxFactorH = 0;
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// Component-specification parameters
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for (int c = 0; c < _numScanComp; c++) {
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// Read the desired component id
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uint8 id = _stream->readByte();
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// Search the component with the specified id
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bool found = false;
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for (int i = 0; !found && i < _numComp; i++) {
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if (_components[i].id == id) {
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// We found the desired component
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found = true;
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// Assign the found component to the c'th scan component
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_scanComp[c] = &_components[i];
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}
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}
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if (!found) {
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warning("JPEG: Invalid component");
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return false;
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}
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// Read the entropy table selectors
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_scanComp[c]->DCentropyTableSelector = _stream->readByte();
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_scanComp[c]->ACentropyTableSelector = _scanComp[c]->DCentropyTableSelector & 0xF;
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_scanComp[c]->DCentropyTableSelector >>= 4;
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// Calculate the maximum sampling factors
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if (_scanComp[c]->factorV > _maxFactorV)
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_maxFactorV = _scanComp[c]->factorV;
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if (_scanComp[c]->factorH > _maxFactorH)
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_maxFactorH = _scanComp[c]->factorH;
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// Initialize the DC predictor
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_scanComp[c]->DCpredictor = 0;
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}
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// Start of spectral selection
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if (_stream->readByte() != 0) {
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warning("JPEG: Progressive scanning not supported");
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return false;
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}
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// End of spectral selection
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if (_stream->readByte() != 63) {
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warning("JPEG: Progressive scanning not supported");
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return false;
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}
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// Successive approximation parameters
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if (_stream->readByte() != 0) {
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warning("JPEG: Progressive scanning not supported");
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return false;
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}
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// Entropy coded sequence starts, initialize Huffman decoder
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_bitsNumber = 0;
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// Read all the scan MCUs
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uint16 xMCU = _w / (_maxFactorH * 8);
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uint16 yMCU = _h / (_maxFactorV * 8);
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// Check for non- multiple-of-8 dimensions
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if (_w % (_maxFactorH * 8) != 0)
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xMCU++;
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if (_h % (_maxFactorV * 8) != 0)
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yMCU++;
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// Initialize the scan surfaces
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for (uint16 c = 0; c < _numScanComp; c++) {
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_scanComp[c]->surface.create(xMCU * _maxFactorH * 8, yMCU * _maxFactorV * 8, 1);
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}
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bool ok = true;
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for (int y = 0; ok && (y < yMCU); y++)
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for (int x = 0; ok && (x < xMCU); x++)
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ok = readMCU(x, y);
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// Trim Component surfaces back to image height and width
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// Note: Code using jpeg must use surface.pitch correctly...
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for (uint16 c = 0; c < _numScanComp; c++) {
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_scanComp[c]->surface.w = _w;
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_scanComp[c]->surface.h = _h;
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}
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return ok;
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}
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// Marker 0xDB (Define Quantization Tables)
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bool JPEG::readDQT() {
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debug(5, "JPEG: readDQT");
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uint16 size = _stream->readUint16BE() - 2;
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uint32 pos = _stream->pos();
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while ((uint32)_stream->pos() < (pos + size)) {
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// Read the table precision and id
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uint8 tableId = _stream->readByte();
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bool highPrecision = (tableId & 0xF0) != 0;
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// Validate the table id
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tableId &= 0xF;
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if (tableId > JPEG_MAX_QUANT_TABLES) {
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warning("JPEG: Invalid number of components");
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return false;
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}
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// Create the new table if necessary
|
|
if (!_quant[tableId])
|
|
_quant[tableId] = new uint16[64];
|
|
|
|
// Read the table (stored in Zig-Zag order)
|
|
for (int i = 0; i < 64; i++)
|
|
_quant[tableId][i] = highPrecision ? _stream->readUint16BE() : _stream->readByte();
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool JPEG::readMCU(uint16 xMCU, uint16 yMCU) {
|
|
bool ok = true;
|
|
for (int c = 0; ok && (c < _numComp); c++) {
|
|
// Set the current component
|
|
_currentComp = _scanComp[c];
|
|
|
|
// Read the data units of the current component
|
|
for (int y = 0; ok && (y < _scanComp[c]->factorV); y++)
|
|
for (int x = 0; ok && (x < _scanComp[c]->factorH); x++)
|
|
ok = readDataUnit(xMCU * _scanComp[c]->factorH + x, yMCU * _scanComp[c]->factorV + y);
|
|
}
|
|
|
|
return ok;
|
|
}
|
|
|
|
void JPEG::idct8x8(float result[64], const int16 dct[64]) {
|
|
float tmp[64];
|
|
|
|
// Apply 1D IDCT to rows
|
|
for (int y = 0; y < 8; y++) {
|
|
for (int x = 0; x < 8; x++) {
|
|
tmp[y + x * 8] = dct[0] * _idct8x8[x][0]
|
|
+ dct[1] * _idct8x8[x][1]
|
|
+ dct[2] * _idct8x8[x][2]
|
|
+ dct[3] * _idct8x8[x][3]
|
|
+ dct[4] * _idct8x8[x][4]
|
|
+ dct[5] * _idct8x8[x][5]
|
|
+ dct[6] * _idct8x8[x][6]
|
|
+ dct[7] * _idct8x8[x][7];
|
|
}
|
|
|
|
dct += 8;
|
|
}
|
|
|
|
// Apply 1D IDCT to columns
|
|
for (int x = 0; x < 8; x++) {
|
|
const float *u = tmp + x * 8;
|
|
for (int y = 0; y < 8; y++) {
|
|
result[y * 8 + x] = u[0] * _idct8x8[y][0]
|
|
+ u[1] * _idct8x8[y][1]
|
|
+ u[2] * _idct8x8[y][2]
|
|
+ u[3] * _idct8x8[y][3]
|
|
+ u[4] * _idct8x8[y][4]
|
|
+ u[5] * _idct8x8[y][5]
|
|
+ u[6] * _idct8x8[y][6]
|
|
+ u[7] * _idct8x8[y][7];
|
|
}
|
|
}
|
|
}
|
|
|
|
bool JPEG::readDataUnit(uint16 x, uint16 y) {
|
|
// Prepare an empty data array
|
|
int16 readData[64];
|
|
for (int i = 1; i < 64; i++)
|
|
readData[i] = 0;
|
|
|
|
// Read the DC component
|
|
readData[0] = _currentComp->DCpredictor + readDC();
|
|
_currentComp->DCpredictor = readData[0];
|
|
|
|
// Read the AC components (stored in Zig-Zag)
|
|
readAC(readData);
|
|
|
|
// Calculate the DCT coefficients from the input sequence
|
|
int16 DCT[64];
|
|
for (uint8 i = 0; i < 64; i++) {
|
|
// Dequantize
|
|
int16 val = readData[i];
|
|
int16 quant = _quant[_currentComp->quantTableSelector][i];
|
|
val *= quant;
|
|
|
|
// Store the normalized coefficients, undoing the Zig-Zag
|
|
DCT[_zigZagOrder[i]] = val;
|
|
}
|
|
|
|
// Apply the IDCT
|
|
float result[64];
|
|
idct8x8(result, DCT);
|
|
|
|
// Level shift to make the values unsigned
|
|
for (int i = 0; i < 64; i++) {
|
|
result[i] = result[i] + 128;
|
|
|
|
if (result[i] < 0)
|
|
result[i] = 0;
|
|
|
|
if (result[i] > 255)
|
|
result[i] = 255;
|
|
}
|
|
|
|
// Paint the component surface
|
|
uint8 scalingV = _maxFactorV / _currentComp->factorV;
|
|
uint8 scalingH = _maxFactorH / _currentComp->factorH;
|
|
|
|
// Convert coordinates from MCU blocks to pixels
|
|
x <<= 3;
|
|
y <<= 3;
|
|
|
|
for (uint8 j = 0; j < 8; j++) {
|
|
for (uint16 sV = 0; sV < scalingV; sV++) {
|
|
// Get the beginning of the block line
|
|
byte *ptr = (byte *)_currentComp->surface.getBasePtr(x * scalingH, (y + j) * scalingV + sV);
|
|
|
|
for (uint8 i = 0; i < 8; i++) {
|
|
for (uint16 sH = 0; sH < scalingH; sH++) {
|
|
*ptr = (byte)(result[j * 8 + i]);
|
|
ptr++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
int16 JPEG::readDC() {
|
|
// DC is type 0
|
|
uint8 tableNum = _currentComp->DCentropyTableSelector << 1;
|
|
|
|
// Get the number of bits to read
|
|
uint8 numBits = readHuff(tableNum);
|
|
|
|
// Read the requested bits
|
|
return readSignedBits(numBits);
|
|
}
|
|
|
|
void JPEG::readAC(int16 *out) {
|
|
// AC is type 1
|
|
uint8 tableNum = (_currentComp->ACentropyTableSelector << 1) + 1;
|
|
|
|
// Start reading AC element 1
|
|
uint8 cur = 1;
|
|
while (cur < 64) {
|
|
uint8 s = readHuff(tableNum);
|
|
uint8 r = s >> 4;
|
|
s &= 0xF;
|
|
|
|
if (s == 0) {
|
|
if (r == 15) {
|
|
// Skip 16 values
|
|
cur += 16;
|
|
} else {
|
|
// EOB: end of block
|
|
cur = 64;
|
|
}
|
|
} else {
|
|
// Skip r values
|
|
cur += r;
|
|
|
|
// Read the next value
|
|
out[cur] = readSignedBits(s);
|
|
cur++;
|
|
}
|
|
}
|
|
}
|
|
|
|
int16 JPEG::readSignedBits(uint8 numBits) {
|
|
uint16 ret = 0;
|
|
if (numBits > 16) error("requested %d bits", numBits); //XXX
|
|
|
|
// MSB=0 for negatives, 1 for positives
|
|
for (int i = 0; i < numBits; i++)
|
|
ret = (ret << 1) + readBit();
|
|
|
|
// Extend sign bits (PAG109)
|
|
if (!(ret >> (numBits - 1)))
|
|
{
|
|
uint16 tmp = ((uint16)-1 << numBits) + 1;
|
|
ret = ret + tmp;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
// TODO: optimize?
|
|
uint8 JPEG::readHuff(uint8 table) {
|
|
bool foundCode = false;
|
|
uint8 val = 0;
|
|
|
|
uint8 cur = 0;
|
|
uint8 codeSize = 1;
|
|
uint16 code = readBit();
|
|
while (!foundCode) {
|
|
// Prepare a code of the current size
|
|
while (codeSize < _huff[table].sizes[cur]) {
|
|
code = (code << 1) + readBit();
|
|
codeSize++;
|
|
}
|
|
|
|
// Compare the codes of the current size
|
|
while (!foundCode && (codeSize == _huff[table].sizes[cur])) {
|
|
if (code == _huff[table].codes[cur]) {
|
|
// Found the code
|
|
val = _huff[table].values[cur];
|
|
foundCode = true;
|
|
} else {
|
|
// Continue reading
|
|
cur++;
|
|
}
|
|
}
|
|
}
|
|
|
|
return val;
|
|
}
|
|
|
|
uint8 JPEG::readBit() {
|
|
// Read a whole byte if necessary
|
|
if (_bitsNumber == 0) {
|
|
_bitsData = _stream->readByte();
|
|
_bitsNumber = 8;
|
|
|
|
// Detect markers
|
|
if (_bitsData == 0xFF) {
|
|
uint8 byte2 = _stream->readByte();
|
|
|
|
// A stuffed 0 validates the previous byte
|
|
if (byte2 != 0) {
|
|
if (byte2 == 0xDC) {
|
|
// DNL marker: Define Number of Lines
|
|
// TODO: terminate scan
|
|
printf("DNL marker detected: terminate scan\n");
|
|
} else {
|
|
printf("Error: marker 0x%02X read in entropy data\n", byte2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
_bitsNumber--;
|
|
|
|
return (_bitsData & (1 << _bitsNumber)) ? 1 : 0;
|
|
}
|
|
|
|
Surface *JPEG::getComponent(uint c) {
|
|
for (int i = 0; i < _numComp; i++)
|
|
if (_components[i].id == c) // We found the desired component
|
|
return &_components[i].surface;
|
|
|
|
error("JPEG::getComponent: No component %d present", c);
|
|
return NULL;
|
|
}
|
|
|
|
} // End of Graphics namespace
|