get rid of the stream parsing that occurs in the Layer III decoder. BitStream.readFra...

[IRC.git] / Robust / src / Tests / ssJava / mp3decoder / SideInfoBuffer.java

diff --git a/Robust/src/Tests/ssJava/mp3decoder/SideInfoBuffer.java b/Robust/src/Tests/ssJava/mp3decoder/SideInfoBuffer.java
new file mode 100644 (file)
index 0000000..d3a3e1d
--- /dev/null
+++ b/Robust/src/Tests/ssJava/mp3decoder/SideInfoBuffer.java
@@ -0,0 +1,85 @@
+public class SideInfoBuffer {
+
+       /**
+        * The frame buffer that holds the data for the current frame.
+        */
+       private final int[] framebuffer = new int[BUFFER_INT_SIZE];
+
+       /**
+        * Maximum size of the frame buffer.
+        */
+       private static final int BUFFER_INT_SIZE = 433;
+
+       /**
+        * Index into <code>framebuffer</code> where the next bits are retrieved.
+        */
+       private int wordpointer;
+
+       /**
+        * Number (0-31, from MSB to LSB) of next bit for get_bits()
+        */
+       private int bitindex;
+
+       private int main_data_begin;
+
+       public int getMain_data_begin() {
+               return main_data_begin;
+       }
+
+       public void setMain_data_begin(int main_data_begin) {
+               this.main_data_begin = main_data_begin;
+       }
+
+       private final int bitmask[] = {
+                       0, // dummy
+                       0x00000001, 0x00000003, 0x00000007, 0x0000000F, 0x0000001F,
+                       0x0000003F, 0x0000007F, 0x000000FF, 0x000001FF, 0x000003FF,
+                       0x000007FF, 0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF,
+                       0x0000FFFF, 0x0001FFFF };
+
+       public int get_bits(int number_of_bits) {
+               int returnvalue = 0;
+               int sum = bitindex + number_of_bits;
+               // System.out.println("bitindex=" + bitindex + " wordpointer="
+               // + wordpointer);
+               // E.B
+               // There is a problem here, wordpointer could be -1 ?!
+               if (wordpointer < 0)
+                       wordpointer = 0;
+               // E.B : End.
+
+               if (sum <= 32) {
+                       // all bits contained in *wordpointer
+                       returnvalue = (framebuffer[wordpointer] >>> (32 - sum))
+                                       & bitmask[number_of_bits];
+                       // returnvalue = (wordpointer[0] >> (32 - sum)) &
+                       // bitmask[number_of_bits];
+                       if ((bitindex += number_of_bits) == 32) {
+                               bitindex = 0;
+                               wordpointer++; // added by me!
+                       }
+                       return returnvalue;
+               }
+
+               // E.B : Check that ?
+               // ((short[])&returnvalue)[0] = ((short[])wordpointer + 1)[0];
+               // wordpointer++; // Added by me!
+               // ((short[])&returnvalue + 1)[0] = ((short[])wordpointer)[0];
+               int Right = (framebuffer[wordpointer] & 0x0000FFFF);
+               wordpointer++;
+               int Left = (framebuffer[wordpointer] & 0xFFFF0000);
+               returnvalue = ((Right << 16) & 0xFFFF0000)
+                               | ((Left >>> 16) & 0x0000FFFF);
+
+               returnvalue >>>= 48 - sum; // returnvalue >>= 16 - (number_of_bits - (32
+                                                                       // - bitindex))
+               returnvalue &= bitmask[number_of_bits];
+               bitindex = sum - 32;
+               return returnvalue;
+       }
+
+       public void setBuffer(int idx, int value) {
+               framebuffer[idx] = value;
+       }
+
+}