--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/intercom/g711/shiftbit.c	Fri Jun 25 09:57:52 2010 +0200
@@ -0,0 +1,120 @@
+/*
+   =======================================================================
+
+   SHIFTBIT.C
+   ~~~~~~~~~~
+
+   Description
+   ~~~~~~~~~~~
+
+   Shift samples from input file (in Qx format) such that the output file
+   will be in the Qy format, with sign extension. In fact, what this does
+   is multiply by the factor 2**(y-x) (if left-shift) or divide by the
+   factor 2**(x-y) (if right-shift) the input samples.
+
+   Includes:
+   ~~~~~~~~~
+      specific: ugstdemo.h
+      system:   stdio.h,stat.h
+
+   Author:
+   ~~~~~~~
+
+   Simao Ferraz de Campos Neto
+   DDS/Pr11                      Tel: +55-192-39-1396                
+   CPqD/Telebras                 Fax: +55-192-53-4754                
+   13085 Campinas SP Brazil      E-mail: <tdsimao@venus.cpqd.ansp.br>
+                                       
+   History:
+   ~~~~~~~~
+   08.Feb.91 v1.0 Created!
+
+   =======================================================================
+*/
+
+#include "ugstdemo.h"
+#include <stdio.h>
+
+/* 
+ * Includes dependent of the Operating System 
+ */
+#if defined(VMS)
+# include <stat.h>
+#elif defined (MSDOS)
+# include <sys\stat.h>
+#else
+# include <sys/stat.h>
+#endif
+
+#define RIGHT 1
+#define LEFT -1
+
+main(argc, argv)
+int argc;
+char *argv[];
+{
+  char inp[50], out[50];
+  short *buf;
+  int qinp, qout, shift, dir;
+  FILE *Fi, *Fo;
+  int fi, fo;
+#ifdef VMS
+  char mrs[15] = "mrs=512";
+#endif
+  struct stat info;
+  long l, k;
+
+  GET_PAR_S(1, "Input file: ......... ", inp);
+  GET_PAR_I(2, "Input file is Q.", qinp);
+  GET_PAR_S(3, "Output file: ........ ", out);
+  GET_PAR_I(4, "Input file is Q.", qout);
+
+  if (qout == qinp)
+    HARAKIRI("Makes no sense a shift of 0 ... \n", 7)
+      else
+  if (qout > qinp)
+    dir = RIGHT;
+  else
+    dir = LEFT;
+
+  l = qout - qinp;
+  if (l < 0)
+    l = -l;
+
+  for (shift = 1, k = 0; k < l; k++)
+    shift *= 2;
+
+  if ((Fi = fopen(inp, RB)) == NULL)
+    KILL(inp, 2);
+  fi = fileno(Fi);
+  if ((Fo = fopen(out, WB)) == NULL)
+    KILL(inp, 3);
+  fo = fileno(Fo);
+
+  stat(inp, &info);
+  if ((buf = (short *) malloc(info.st_size)) == NULL)
+    HARAKIRI("Can't alloc inp\n", 4);
+  l = info.st_size / 2;
+
+  fprintf(stderr, "%s: Reading, ", inp);
+  for (k = 0; k < l; k += 256)
+    if (read(fi, &buf[k], 512) < 0)
+      KILL(inp, 5);
+
+  fprintf(stderr, "shifting, ");
+  if (dir == RIGHT)
+    for (k = 0; k < l; k++)
+      buf[k] = (buf[k] * shift);
+  else
+    for (k = 0; k < l; k++)
+      buf[k] = (buf[k] / shift);
+
+  fprintf(stderr, "and writing ... ");
+  for (k = 0; k < l; k += 256)
+    if (write(fo, &buf[k], 512) <= 0)
+      KILL(inp, 6);
+
+  fprintf(stderr, "Done!\n");
+  fclose(Fi);
+  fclose(Fo);
+}