Changeset 7178

Timestamp:

02/27/08 04:57:51 (5 years ago)

Author:

kazuho

Message:

elementsof(freq) should be 257 including total freq. at the end
use a safer method for rounding the frequency table

Files:

• lang/cplusplus/range_coder/build_table.pl (modified) (1 diff)

lang/cplusplus/range_coder/build_table.pl

@@ -32 +32 @@
 
 my @freq;
-my $acc = 0;
 my $cc = sum @cnt;
-my ($mult, $mult_diff) = (0x8000, 0);
+my $mult = 0x8000;
 while (1) {
-    $acc = 0;
+    print STDERR "$mult\n";
+    my $acc = 0;
     for (my $i = 0; $i < 256; $i++) {
         push @freq, $acc;
         $acc += $cnt[$i] != 0 ? max(int($cnt[$i] / $cc * $mult + 0.5), 1) : 0;
     }
-    last if $acc == 0x8000;
+    last if $acc <= 0x8000;
     @freq = ();
-    $mult_diff = $mult_diff != 0 ? $mult_diff / 2 : abs($acc - 0x8000);
-    if ($acc < 0x8000) {
-        $mult += $mult_diff;
-    } else {
-        $mult -= $mult_diff;
-    }
+    $mult--;
 }
+push @freq, 0x8000;
 
 print "#define MAX_FREQ 0x8000\n";