1 files changed, 166 insertions, 0 deletions
diff --git a/akode/plugins/mpc_decoder/mppdec/bitstream.cpp b/akode/plugins/mpc_decoder/mppdec/bitstream.cpp
new file mode 100644
index 0000000..6e1714c
--- /dev/null
+++ b/akode/plugins/mpc_decoder/mppdec/bitstream.cpp
@@ -0,0 +1,166 @@
+#include "stdafx.h"
+
+
+/* C O N S T A N T S */
+const unsigned int  mask [33] = {
+    0x00000000, 0x00000001, 0x00000003, 0x00000007,
+    0x0000000F, 0x0000001F, 0x0000003F, 0x0000007F,
+    0x000000FF, 0x000001FF, 0x000003FF, 0x000007FF,
+    0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF,
+    0x0000FFFF, 0x0001FFFF, 0x0003FFFF, 0x0007FFFF,
+    0x000FFFFF, 0x001FFFFF, 0x003FFFFF, 0x007FFFFF,
+    0x00FFFFFF, 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF,
+    0x0FFFFFFF, 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF,
+    0xFFFFFFFF
+};
+
+/* F U N C T I O N S */
+
+// resets bitstream decoding
+void
+MPC_decoder::Reset_BitstreamDecode ( void )
+{
+    dword     = 0;
+    pos       = 0;
+    Zaehler   = 0;
+    WordsRead = 0;
+}
+
+// reports the number of read bits
+unsigned int
+MPC_decoder::BitsRead ( void )
+{
+    return 32*WordsRead + pos;
+}
+
+// read desired number of bits out of the bitstream
+unsigned int
+MPC_decoder::Bitstream_read ( const unsigned int bits )
+{
+    unsigned int out = dword;
+
+    pos += bits;
+
+    if (pos<32)
+    {
+        out >>= (32-pos);
+    }
+    else
+    {
+        dword = Speicher[Zaehler=(Zaehler+1)&MEMMASK];
+        pos -= 32;
+        if (pos)
+        {
+            out <<= pos;
+            out |= dword >> (32-pos);
+        }
+        ++WordsRead;
+    }
+
+    return out & mask[bits];
+}
+
+// decode huffman
+int
+MPC_decoder::Huffman_Decode ( const HuffmanTyp* Table )
+{
+    // load preview and decode
+    unsigned int code  = dword << pos;
+    if (pos>18)  code |= Speicher[(Zaehler+1)&MEMMASK] >> (32-pos);
+    while (code < Table->Code) Table++;
+
+    // set the new position within bitstream without performing a dummy-read
+    if ((pos += Table->Length)>=32)
+    {
+        pos -= 32;
+        dword = Speicher[Zaehler=(Zaehler+1)&MEMMASK];
+        ++WordsRead;
+    }
+
+    return Table->Value;
+}
+
+// faster huffman through previewing less bits
+int
+MPC_decoder::Huffman_Decode_fast ( const HuffmanTyp* Table )
+{
+    // load preview and decode
+    unsigned int code  = dword << pos;
+    if (pos>22)  code |= Speicher[(Zaehler+1)&MEMMASK] >> (32-pos);
+    while (code < Table->Code) Table++;
+
+    // set the new position within bitstream without performing a dummy-read
+    if ((pos += Table->Length)>=32)
+    {
+        pos -= 32;
+        dword = Speicher[Zaehler=(Zaehler+1)&MEMMASK];
+        ++WordsRead;
+    }
+
+    return Table->Value;
+}
+
+// even faster huffman through previewing even less bits
+int
+MPC_decoder::Huffman_Decode_faster ( const HuffmanTyp* Table )
+{
+    // load preview and decode
+    unsigned int code  = dword << pos;
+    if (pos>27)  code |= Speicher[(Zaehler+1)&MEMMASK] >> (32-pos);
+    while (code < Table->Code) Table++;
+
+    // set the new position within bitstream without performing a dummy-read
+    if ((pos += Table->Length)>=32)
+    {
+        pos -= 32;
+        dword = Speicher[Zaehler=(Zaehler+1)&MEMMASK];
+        ++WordsRead;
+    }
+
+    return Table->Value;
+}
+
+// decode SCFI-bundle (sv4,5,6)
+void
+MPC_decoder::SCFI_Bundle_read ( const HuffmanTyp* Table, int* SCFI, int* DSCF )
+{
+    // load preview and decode
+    unsigned int code  = dword << pos;
+    if (pos>26)  code |= Speicher[(Zaehler+1)&MEMMASK] >> (32-pos);
+    while (code < Table->Code) Table++;
+
+    // set the new position within bitstream without performing a dummy-read
+    if ((pos += Table->Length)>=32)
+    {
+        pos -= 32;
+        dword = Speicher[Zaehler=(Zaehler+1)&MEMMASK];
+        ++WordsRead;
+    }
+
+    *SCFI = Table->Value >> 1;
+    *DSCF = Table->Value &  1;
+}
+
+int
+MPC_decoder::HuffmanTyp_cmpfn ( const void* p1, const void* p2 )
+{
+    if ( ((const MPC_decoder::HuffmanTyp*) p1)->Code < ((const MPC_decoder::HuffmanTyp*) p2)->Code ) return +1;
+    if ( ((const MPC_decoder::HuffmanTyp*) p1)->Code > ((const MPC_decoder::HuffmanTyp*) p2)->Code ) return -1;
+    return 0;
+}
+
+// sort huffman-tables by codeword
+// offset resulting value
+void
+MPC_decoder::Resort_HuffTables ( const unsigned int elements, HuffmanTyp* Table, const int offset )
+{
+    unsigned int  i;
+
+    for ( i = 0; i < elements; i++ ) {
+        Table[i].Code <<= 32 - Table[i].Length;
+        Table[i].Value  =  i - offset;
+    }
+    qsort ( Table, elements, sizeof(*Table), HuffmanTyp_cmpfn );
+}
+
+/* end of bitstream.c */