Changeset 161 for libmpc/branches/r2d/mppenc/mppenc.c

Timestamp:

12/18/06 20:52:54 (18 years ago)

Author:

r2d

Message:

• changed entropy coding (all huffman tables are canonical)
• scalefactor range now -6..121, no more clipping
• compression gain is 2.36% on the test file

File:

• libmpc/branches/r2d/mppenc/mppenc.c (modified) (3 diffs)

libmpc/branches/r2d/mppenc/mppenc.c

@@ -546 +546 @@
         if (tmp_R [2] > 0.) scfR [2] = IFLOORF (-12.6f * LOG10 (tmp_R [2]) + 57.8945021823f );
 
-        // restriction to SCF_Index = 0...63, make note of the internal overflow
+        // restriction to SCF_Index = -6...121, make note of the internal overflow
         warnL = warnR = 0;
-        if (scfL[0] & ~63) { if (scfL[0] < 0) { if (XLevel==0) scfL[0] = 0, warnL = 1; } else scfL[0] = 63; }
-        if (scfL[1] & ~63) { if (scfL[1] < 0) { if (XLevel==0) scfL[1] = 0, warnL = 1; } else scfL[1] = 63; }
-        if (scfL[2] & ~63) { if (scfL[2] < 0) { if (XLevel==0) scfL[2] = 0, warnL = 1; } else scfL[2] = 63; }
-        if (scfR[0] & ~63) { if (scfR[0] < 0) { if (XLevel==0) scfR[0] = 0, warnR = 1; } else scfR[0] = 63; }
-        if (scfR[1] & ~63) { if (scfR[1] < 0) { if (XLevel==0) scfR[1] = 0, warnR = 1; } else scfR[1] = 63; }
-        if (scfR[2] & ~63) { if (scfR[2] < 0) { if (XLevel==0) scfR[2] = 0, warnR = 1; } else scfR[2] = 63; }
+                for( n = 0; n < 3; n++){
+                        if (scfL[n] < -6) scfL[n] = -6, warnL = 1;
+                        if (scfL[n] > 121) scfL[n] = 121, warnL = 1;
+                        if (scfR[n] < -6) scfR[n] = -6, warnR = 1;
+                        if (scfR[n] > 121) scfR[n] = 121, warnR = 1;
+                }
 
         // save old values for compensation calculation
@@ -1462 +1462 @@
     cw  &=  ~0x300;
         _asm { fldcw cw };
-#else
-    ;
 #endif
 }
@@ -1718 +1716 @@
 
         OldSilence      = Silence;
-        WriteBitstream_SV7 ( &e, m.Max_Band, Q );                                                // write SV7-Bitstream
+        writeBitstream_SV8 ( &e, m.Max_Band, Q );                                                // write SV7-Bitstream
 
         if ( (Int)(time (NULL) - T) >= 0 ) {                            // output