--- /dev/null
+/*
+** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include "sfconfig.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include <sndfile.h>
+
+#include "utils.h"
+
+#define BUFFER_SIZE (65536)
+
+static unsigned char ulaw_encode (int sample) ;
+static int ulaw_decode (unsigned int ulawbyte) ;
+
+static short short_buffer [BUFFER_SIZE] ;
+static unsigned char ulaw_buffer [BUFFER_SIZE] ;
+
+int
+main (void)
+{ SNDFILE *file ;
+ SF_INFO sfinfo ;
+ const char *filename ;
+ int k ;
+
+ print_test_name ("ulaw_test", "encoder") ;
+
+ filename = "test.raw" ;
+
+ sf_info_setup (&sfinfo, SF_FORMAT_RAW | SF_FORMAT_ULAW, 44100, 1) ;
+
+ if ((file = sf_open (filename, SFM_WRITE, &sfinfo)) == NULL)
+ { printf ("sf_open_write failed with error : ") ;
+ fflush (stdout) ;
+ puts (sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ /* Generate a file containing all possible 16 bit sample values
+ ** and write it to disk as ulaw encoded.frames.
+ */
+
+ for (k = 0 ; k < 0x10000 ; k++)
+ short_buffer [k] = k & 0xFFFF ;
+
+ sf_write_short (file, short_buffer, BUFFER_SIZE) ;
+ sf_close (file) ;
+
+ /* Now open that file and compare the ulaw encoded sample values
+ ** with what they should be.
+ */
+
+ if ((file = sf_open (filename, SFM_READ, &sfinfo)) == NULL)
+ { printf ("sf_open_write failed with error : ") ;
+ puts (sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ check_log_buffer_or_die (file, __LINE__) ;
+
+ if (sf_read_raw (file, ulaw_buffer, BUFFER_SIZE) != BUFFER_SIZE)
+ { printf ("sf_read_raw : ") ;
+ puts (sf_strerror (file)) ;
+ exit (1) ;
+ } ;
+
+ for (k = 0 ; k < 0x10000 ; k++)
+ if (ulaw_encode (short_buffer [k]) != ulaw_buffer [k])
+ { printf ("Encoder error : sample #%d (0x%02X should be 0x%02X)\n", k, ulaw_buffer [k], ulaw_encode (short_buffer [k])) ;
+ exit (1) ;
+ } ;
+
+ sf_close (file) ;
+
+ puts ("ok") ;
+
+ print_test_name ("ulaw_test", "decoder") ;
+
+ /* Now generate a file containing all possible 8 bit encoded
+ ** sample values and write it to disk as ulaw encoded.frames.
+ */
+
+ if (! (file = sf_open (filename, SFM_WRITE, &sfinfo)))
+ { printf ("sf_open_write failed with error : ") ;
+ puts (sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ for (k = 0 ; k < 256 ; k++)
+ ulaw_buffer [k] = k & 0xFF ;
+
+ sf_write_raw (file, ulaw_buffer, 256) ;
+ sf_close (file) ;
+
+ /* Now open that file and compare the ulaw decoded sample values
+ ** with what they should be.
+ */
+
+ if (! (file = sf_open (filename, SFM_READ, &sfinfo)))
+ { printf ("sf_open_write failed with error : ") ;
+ puts (sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ check_log_buffer_or_die (file, __LINE__) ;
+
+ if (sf_read_short (file, short_buffer, 256) != 256)
+ { printf ("sf_read_short : ") ;
+ puts (sf_strerror (file)) ;
+ exit (1) ;
+ } ;
+
+
+ for (k = 0 ; k < 256 ; k++)
+ if (short_buffer [k] != ulaw_decode (ulaw_buffer [k]))
+ { printf ("Decoder error : sample #%d (0x%04X should be 0x%04X)\n", k, short_buffer [k], ulaw_decode (ulaw_buffer [k])) ;
+ exit (1) ;
+ } ;
+
+ sf_close (file) ;
+
+ puts ("ok") ;
+
+ unlink (filename) ;
+
+ return 0 ;
+} /* main */
+
+
+/*=================================================================================
+** The following routines came from the sox-12.15 (Sound eXcahcnge) distribution.
+**
+** This code is not compiled into libsndfile. It is only used to test the
+** libsndfile lookup tables for correctness.
+**
+** I have included the original authors comments.
+*/
+
+/*
+** This routine converts from linear to ulaw.
+**
+** Craig Reese: IDA/Supercomputing Research Center
+** Joe Campbell: Department of Defense
+** 29 September 1989
+**
+** References:
+** 1) CCITT Recommendation G.711 (very difficult to follow)
+** 2) "A New Digital Technique for Implementation of Any
+** Continuous PCM Companding Law," Villeret, Michel,
+** et al. 1973 IEEE Int. Conf. on Communications, Vol 1,
+** 1973, pg. 11.12-11.17
+** 3) MIL-STD-188-113,"Interoperability and Performance Standards
+** for Analog-to_Digital Conversion Techniques,"
+** 17 February 1987
+**
+** Input: Signed 16 bit linear sample
+** Output: 8 bit ulaw sample
+*/
+
+#define uBIAS 0x84 /* define the add-in bias for 16 bit.frames */
+#define uCLIP 32635
+
+static
+unsigned char ulaw_encode (int sample)
+{ static int exp_lut [256] =
+ { 0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
+ } ;
+
+ int sign, exponent, mantissa ;
+ unsigned char ulawbyte ;
+
+ /* Get the sample into sign-magnitude. */
+ sign = (sample >> 8) & 0x80 ; /* set aside the sign */
+ if ( sign != 0 )
+ sample = -sample ; /* get magnitude */
+ if ( sample > uCLIP )
+ sample = uCLIP ; /* clip the magnitude */
+
+ /* Convert from 16 bit linear to ulaw. */
+ sample = sample + uBIAS ;
+ exponent = exp_lut [( sample >> 7 ) & 0xFF] ;
+ mantissa = (sample >> ( exponent + 3 ) ) & 0x0F ;
+ ulawbyte = ~ (sign | ( exponent << 4 ) | mantissa) ;
+
+ return ulawbyte ;
+} /* ulaw_encode */
+
+
+/*
+** This routine converts from ulaw to 16 bit linear.
+**
+** Craig Reese: IDA/Supercomputing Research Center
+** 29 September 1989
+**
+** References:
+** 1) CCITT Recommendation G.711 (very difficult to follow)
+** 2) MIL-STD-188-113,"Interoperability and Performance Standards
+** for Analog-to_Digital Conversion Techniques,"
+** 17 February 1987
+**
+** Input: 8 bit ulaw sample
+** Output: signed 16 bit linear sample
+*/
+
+static
+int ulaw_decode (unsigned int ulawbyte)
+{ static int exp_lut [8] = { 0, 132, 396, 924, 1980, 4092, 8316, 16764 } ;
+ int sign, exponent, mantissa, sample ;
+
+ ulawbyte = ~ ulawbyte ;
+ sign = (ulawbyte & 0x80) ;
+ exponent = (ulawbyte >> 4) & 0x07 ;
+ mantissa = ulawbyte & 0x0F ;
+ sample = exp_lut [exponent] + (mantissa << (exponent + 3)) ;
+ if (sign != 0)
+ sample = -sample ;
+
+ return sample ;
+} /* ulaw_decode */
+
projects / Faustine.git / blobdiff