diff src/libsndfile-1.0.25/tests/alaw_test.c @ 0:c7265573341e

Import initial set of sources

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/libsndfile-1.0.25/tests/alaw_test.c	Mon Mar 18 14:12:14 2013 +0000
@@ -0,0 +1,236 @@
+/*
+** Copyright (C) 1999-2011 Erik de Castro Lopo <[e-mail]>
+**
+** 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	alaw_encode (int sample) ;
+static int				alaw_decode (unsigned int alawbyte) ;
+
+static	short			short_buffer [BUFFER_SIZE] ;
+static	unsigned char	alaw_buffer [BUFFER_SIZE] ;
+
+int
+main (void)
+{	SNDFILE		*file ;
+	SF_INFO		sfinfo ;
+	const char	*filename ;
+	int			k ;
+
+	print_test_name ("alaw_test", "encoder") ;
+
+	filename = "test.raw" ;
+
+	sf_info_setup (&sfinfo, SF_FORMAT_RAW | SF_FORMAT_ALAW, 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 alaw 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 alaw 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, alaw_buffer, BUFFER_SIZE) != BUFFER_SIZE)
+	{	printf ("sf_read_raw : ") ;
+		puts (sf_strerror (file)) ;
+		exit (1) ;
+		} ;
+
+	for (k = 0 ; k < 0x10000 ; k++)
+		if (alaw_encode (short_buffer [k]) != alaw_buffer [k])
+		{	printf ("Encoder error : sample #%d (0x%02X should be 0x%02X)\n", k, alaw_buffer [k], alaw_encode (short_buffer [k])) ;
+			exit (1) ;
+			} ;
+
+	sf_close (file) ;
+
+	puts ("ok") ;
+
+	print_test_name ("alaw_test", "decoder") ;
+	/* Now generate a file containing all possible 8 bit encoded
+	** sample values and write it to disk as alaw 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++)
+		alaw_buffer [k] = k & 0xFF ;
+
+	sf_write_raw (file, alaw_buffer, 256) ;
+	sf_close (file) ;
+
+	/* Now open that file and compare the alaw 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] != alaw_decode (alaw_buffer [k]))
+		{	printf ("Decoder error : sample #%d (0x%02X should be 0x%02X)\n", k, short_buffer [k], alaw_decode (alaw_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.
+*/
+
+/*
+** A-law routines by Graeme W. Gill.
+** Date: 93/5/7
+**
+** References:
+** 1) CCITT Recommendation G.711
+**
+*/
+
+#define ACLIP 31744
+
+static
+unsigned char alaw_encode (int sample)
+{	static int exp_lut [128] =
+	{	1, 1, 2, 2, 3, 3, 3, 3,
+		4, 4, 4, 4, 4, 4, 4, 4,
+		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,
+		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 Alawbyte ;
+
+    /* Get the sample into sign-magnitude. */
+    sign = ((~sample) >> 8) & 0x80 ;			/* set aside the sign */
+    if (sign == 0)
+		sample = -sample ;		/* get magnitude */
+    if (sample > ACLIP)
+		sample = ACLIP ;						/* clip the magnitude */
+
+    /* Convert from 16 bit linear to ulaw. */
+    if (sample >= 256)
+	{	exponent = exp_lut [(sample >> 8) & 0x7F] ;
+		mantissa = ( sample >> ( exponent + 3 ) ) & 0x0F ;
+		Alawbyte = ((exponent << 4) | mantissa) ;
+		}
+    else
+		Alawbyte = (sample >> 4) ;
+
+	Alawbyte ^= (sign ^ 0x55) ;
+
+    return Alawbyte ;
+} /* alaw_encode */
+
+static
+int alaw_decode (unsigned int Alawbyte)
+{	static int exp_lut [8] = { 0, 264, 528, 1056, 2112, 4224, 8448, 16896 } ;
+    int sign, exponent, mantissa, sample ;
+
+    Alawbyte ^= 0x55 ;
+    sign = (Alawbyte & 0x80) ;
+    Alawbyte &= 0x7f ;			/* get magnitude */
+    if (Alawbyte >= 16)
+	{	exponent = (Alawbyte >> 4 ) & 0x07 ;
+		mantissa = Alawbyte & 0x0F ;
+		sample = exp_lut [exponent] + (mantissa << ( exponent + 3 )) ;
+		}
+    else
+		sample = (Alawbyte << 4) + 8 ;
+    if (sign == 0)
+		sample = -sample ;
+
+    return sample ;
+} /* alaw_decode */
+