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TOAST(1)		    General Commands Manual		      TOAST(1)

       toast --	GSM 06.10 lossy	sound compression

       toast [ -cdfpvhualsFC ] [ filename... ]

       untoast [ -cfpvhuaslF ] [ filename... ]

       tcat [ -vhuaslF ] [ filename... ]

       Toast  compresses the sound files given on its command line.  Each file
       is replaced by a	file with the extension	.gsm .	If no files are	speci-
       fied,  the compression is applied to the	standard input,	and its	result
       is written to standard output.

       Toasted files can be restored to	something not quite unlike their orig-
       inal form by running toast -d , or untoast , on the .gsm-files or stan-
       dard input.

       The program tcat	(the same as running untoast -c	 )   uncompresses  its
       input on	standard output, but leaves the	compressed .gsm-files alone.

       When  files are compressed or uncompressed into other files, the	owner-
       ship (if	run by root), modes, accessed and  modified  times  are	 main-
       tained between both versions.

       -c     (cat) Write to the standard output; no files are changed.

       -d     (decode) Decode, rather than encode, the files.

       -f     (force)  Force replacement of output files if they exist.	 If -f
	      is omitted and toast (or untoast)	is run	interactively  from  a
	      terminal,	 the user is prompted as to whether the	file should be

       -p     (precious) Do not	delete the source files.  Source files are im-
	      plicitly left alone whenever -c is specified or tcat is run.

       -C     (LTP cut-off) Ignore most	sample values when calculating the GSM
	      long-term	correlation lag	during encoding.  (The multiplications
	      that  do this are	a bottleneck of	the algorithm.)	 The resulting
	      encoding process will not	produce	exactly	the  same  results  as
	      GSM 06.10	would, but remains close enough	to be compatible.
	      The  -C  option  applies only to the encoder and is silently ig-
	      nored by the decoder.

       -F     (fast) On	systems	with a floating	point processor, but without a
	      multiplication  instruction,  -F sacrifices standard conformance
	      to performance and nearly	doubles	the speed of the algorithm.
	      The resulting encoding and decoding process will not produce ex-
	      actly  the  same	results	 as GSM	06.10 would, but remains close
	      enough to	be compatible.
	      The default is standard-conforming operation.

       -v     (version)	 outputs the version of	toast (or untoast or tcat)  to
	      stdout and exits.

       -h     (help)  prints a short overview of the options.

       Toast,  untoast and tcat	try to guess the appropriate audio data	format
       from the	file suffix.  Command line options can also specify  a	format
       to be used for all files.
       The following formats are supported:

       -u     (<mu>U-law) 8 kHz, 8 bit <mu>U-law encoding (file	suffix .u)

       -a     (A-law) 8	kHz, 8 bit A-law encoding (file	suffix .A)

       -s     (Sun  audio)  8  kHz, 8 bit <mu>U-law encoding with audio	header
	      (file suffix .au)

       -l     (linear) 8 kHz, 16 bit signed linear encoding in host byte order
	      with 13 significant bits (file suffix .l)

       In absence of options or	suffixes to specify a format, <mu>U-law	encod-
       ing as forced by	-u is assumed.

       A four bit magic	number is prefixed to  each  32	 1/2-byte  GSM	frame,
       mainly because 32 1/2-bytes are rather clumsy to	handle.

       The compression algorithm used is a lossy compression algorithm devised
       especially for speech; on no account should it be used for  text,  pic-
       tures or	any other non-speech-data you consider valuable.

       Please direct bug reports to


				     local			      TOAST(1)


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