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authorclone27272011-07-18 16:04:39 -0700
committerclone27272011-07-18 16:04:39 -0700
commit6370984b2238f90aa3e03ac70725b3cfc671d581 (patch)
tree031784ab3bfc44bff048e3b4d9b9e1e969a22af8 /common/bitstream.cpp
parent85a056f3824151e4f1838de2ca3aeb7e824c32b8 (diff)
parent26d15ce675447070ed5ba99a3b21253b1a4459f7 (diff)
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Merge pull request #50 from clone2727/bink
Add support for Bink video to SCUMM HE
Diffstat (limited to 'common/bitstream.cpp')
-rw-r--r--common/bitstream.cpp217
1 files changed, 217 insertions, 0 deletions
diff --git a/common/bitstream.cpp b/common/bitstream.cpp
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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.
+ *
+ */
+
+// Based on eos' BitStream implementation
+
+#include "common/bitstream.h"
+#include "common/memstream.h"
+#include "common/stream.h"
+#include "common/textconsole.h"
+#include "common/util.h"
+
+namespace Common {
+
+BitStream::BitStream() {
+}
+
+BitStream::~BitStream() {
+}
+
+void BitStream::skip(uint32 n) {
+ while (n-- > 0)
+ getBit();
+}
+
+
+BitStreamBE::BitStreamBE(SeekableReadStream &stream, uint32 bitCount) : _value(0), _inValue(0) {
+ if ((bitCount % 8) != 0)
+ error("Big-endian bit stream size has to be divisible by 8");
+
+ // Read the number of bytes of the stream
+
+ uint32 byteSize = bitCount / 8;
+ byte *data = (byte *)malloc(byteSize);
+
+ if (stream.read(data, byteSize) != byteSize) {
+ free(data);
+ error("Bad BitStreamBE size");
+ }
+
+ _stream = new MemoryReadStream(data, byteSize, DisposeAfterUse::YES);
+}
+
+BitStreamBE::BitStreamBE(const byte *data, uint32 bitCount) : _value(0), _inValue(0) {
+ if ((bitCount % 8) != 0)
+ error("Big-endian bit stream size has to be divisible by 8");
+
+ // Copy the number of bytes from the data array
+
+ uint32 byteSize = bitCount / 8;
+ byte *dataN = (byte *)malloc(byteSize);
+
+ memcpy(dataN, data, byteSize);
+
+ _stream = new MemoryReadStream(dataN, byteSize, DisposeAfterUse::YES);
+}
+
+BitStreamBE::~BitStreamBE() {
+ delete _stream;
+}
+
+uint32 BitStreamBE::getBit() {
+ if (_inValue == 0) {
+ // Need to get new byte
+
+ if (_stream->eos())
+ error("End of bit stream reached");
+
+ _value = _stream->readByte();
+ }
+
+ // Get the current bit
+ int b = ((_value & 0x80) == 0) ? 0 : 1;
+
+ // Shift to the next bit
+ _value <<= 1;
+
+ // Increase the position within the current byte
+ _inValue = (_inValue + 1) % 8;
+
+ return b;
+}
+
+uint32 BitStreamBE::getBits(uint32 n) {
+ if (n > 32)
+ error("Too many bits requested to be read");
+
+ // Read the number of bits
+ uint32 v = 0;
+ while (n-- > 0)
+ v = (v << 1) | getBit();
+
+ return v;
+}
+
+void BitStreamBE::addBit(uint32 &x, uint32 n) {
+ x = (x << 1) | getBit();
+}
+
+uint32 BitStreamBE::pos() const {
+ if (_stream->pos() == 0)
+ return 0;
+
+ uint32 p = (_inValue == 0) ? _stream->pos() : (_stream->pos() - 1);
+ return p * 8 + _inValue;
+}
+
+uint32 BitStreamBE::size() const {
+ return _stream->size() * 8;
+}
+
+
+BitStream32LE::BitStream32LE(SeekableReadStream &stream, uint32 bitCount) : _value(0), _inValue(0) {
+ if ((bitCount % 32) != 0)
+ error("32bit little-endian bit stream size has to be divisible by 32");
+
+ // Read the number of bytes of the stream
+
+ uint32 byteSize = bitCount / 8;
+ byte *data = (byte *)malloc(byteSize);
+
+ if (stream.read(data, byteSize) != byteSize) {
+ free(data);
+ error("Bad BitStream32LE size");
+ }
+
+ _stream = new MemoryReadStream(data, byteSize, DisposeAfterUse::YES);
+}
+
+BitStream32LE::BitStream32LE(const byte *data, uint32 bitCount) : _value(0), _inValue(0) {
+ if ((bitCount % 32) != 0)
+ error("32bit little-endian bit stream size has to be divisible by 32");
+
+ // Copy the number of bytes from the data array
+
+ uint32 byteSize = bitCount / 8;
+ byte *dataN = (byte *)malloc(byteSize);
+
+ memcpy(dataN, data, byteSize);
+
+ _stream = new MemoryReadStream(dataN, byteSize, DisposeAfterUse::YES);
+}
+
+BitStream32LE::~BitStream32LE() {
+ delete _stream;
+}
+
+uint32 BitStream32LE::getBit() {
+ if (_inValue == 0) {
+ // Need to get new 32bit value
+
+ if (_stream->eos())
+ error("End of bit stream reached");
+
+ _value = _stream->readUint32LE();
+ }
+
+ // Get the current bit
+ int b = ((_value & 1) == 0) ? 0 : 1;
+
+ // Shift to the next bit
+ _value >>= 1;
+
+ // Increase the position within the current byte
+ _inValue = (_inValue + 1) % 32;
+
+ return b;
+}
+
+uint32 BitStream32LE::getBits(uint32 n) {
+ if (n > 32)
+ error("Too many bits requested to be read");
+
+ // Read the number of bits
+ uint32 v = 0;
+ for (uint32 i = 0; i < n; i++)
+ v = (v >> 1) | (((uint32) getBit()) << 31);
+
+ v >>= (32 - n);
+ return v;
+}
+
+void BitStream32LE::addBit(uint32 &x, uint32 n) {
+ x = (x & ~(1 << n)) | (getBit() << n);
+}
+
+uint32 BitStream32LE::pos() const {
+ if (_stream->pos() == 0)
+ return 0;
+
+ uint32 p = ((_inValue == 0) ? _stream->pos() : (_stream->pos() - 1)) & 0xFFFFFFFC;
+ return p * 8 + _inValue;
+}
+
+uint32 BitStream32LE::size() const {
+ return _stream->size() * 8;
+}
+
+} // End of namespace Common