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diff --git a/gr-vocoder/lib/g7xx/README b/gr-vocoder/lib/g7xx/README deleted file mode 100644 index 23b0e7dd5..000000000 --- a/gr-vocoder/lib/g7xx/README +++ /dev/null @@ -1,94 +0,0 @@ -The files in this directory comprise ANSI-C language reference implementations -of the CCITT (International Telegraph and Telephone Consultative Committee) -G.711, G.721 and G.723 voice compressions. They have been tested on Sun -SPARCstations and passed 82 out of 84 test vectors published by CCITT -(Dec. 20, 1988) for G.721 and G.723. [The two remaining test vectors, -which the G.721 decoder implementation for u-law samples did not pass, -may be in error because they are identical to two other vectors for G.723_40.] - -This source code is released by Sun Microsystems, Inc. to the public domain. -Please give your acknowledgement in product literature if this code is used -in your product implementation. - -Sun Microsystems supports some CCITT audio formats in Solaris 2.0 system -software. However, Sun's implementations have been optimized for higher -performance on SPARCstations. - - -The source files for CCITT conversion routines in this directory are: - - g72x.h header file for g721.c, g723_24.c and g723_40.c - g711.c CCITT G.711 u-law and A-law compression - g72x.c common denominator of G.721 and G.723 ADPCM codes - g721.c CCITT G.721 32Kbps ADPCM coder (with g72x.c) - g723_24.c CCITT G.723 24Kbps ADPCM coder (with g72x.c) - g723_40.c CCITT G.723 40Kbps ADPCM coder (with g72x.c) - - -Simple conversions between u-law, A-law, and 16-bit linear PCM are invoked -as follows: - - unsigned char ucode, acode; - short pcm_val; - - ucode = linear2ulaw(pcm_val); - ucode = alaw2ulaw(acode); - - acode = linear2alaw(pcm_val); - acode = ulaw2alaw(ucode); - - pcm_val = ulaw2linear(ucode); - pcm_val = alaw2linear(acode); - - -The other CCITT compression routines are invoked as follows: - - #include "g72x.h" - - struct g72x_state state; - int sample, code; - - g72x_init_state(&state); - code = {g721,g723_24,g723_40}_encoder(sample, coding, &state); - sample = {g721,g723_24,g723_40}_decoder(code, coding, &state); - -where - coding = AUDIO_ENCODING_ULAW for 8-bit u-law samples - AUDIO_ENCODING_ALAW for 8-bit A-law samples - AUDIO_ENCODING_LINEAR for 16-bit linear PCM samples - - - -This directory also includes the following sample programs: - - encode.c CCITT ADPCM encoder - decode.c CCITT ADPCM decoder - Makefile makefile for the sample programs - - -The sample programs contain examples of how to call the various compression -routines and pack/unpack the bits. The sample programs read byte streams from -stdin and write to stdout. The input/output data is raw data (no file header -or other identifying information is embedded). The sample programs are -invoked as follows: - - encode [-3|4|5] [-a|u|l] <infile >outfile - decode [-3|4|5] [-a|u|l] <infile >outfile -where: - -3 encode to (decode from) G.723 24kbps (3-bit) data - -4 encode to (decode from) G.721 32kbps (4-bit) data [the default] - -5 encode to (decode from) G.723 40kbps (5-bit) data - -a encode from (decode to) A-law data - -u encode from (decode to) u-law data [the default] - -l encode from (decode to) 16-bit linear data - -Examples: - # Read 16-bit linear and output G.721 - encode -4 -l <pcmfile >g721file - - # Read 40Kbps G.723 and output A-law - decode -5 -a <g723file >alawfile - - # Compress and then decompress u-law data using 24Kbps G.723 - encode -3 <ulawin | deoced -3 >ulawout - |