217ecd112b
Using recent versions of parecord produces the following:
Failed to open audio file.
According to the manual:
-r | --record
Capture audio data and write it to the specified file or to STDOUT if none is specified. If the
tool is called under the name parec this is the default.
so we suggest parec instead.
Change-Id: I8b821df67b10e9d6533c4cbe19c646c84d436c27
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@no-log.org>
Reviewed-on: https://review.coreboot.org/23863
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Kocialkowski <contact@paulk.fr>
112 lines
2.5 KiB
C
112 lines
2.5 KiB
C
/* spkmodem-recv.c - decode spkmodem signals */
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/*
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* Copyright (C) 2013 Vladimir 'phcoder' Serbinenko
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*
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* spkmodem-recv is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 2 of the License, or
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* (at your option) any later version.
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*
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* spkmodem-recv is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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/* Compilation: gcc -o spkmodem-recv spkmodem-recv */
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/* Usage: parec --channels=1 --rate=48000 --format=s16le | ./spkmodem-recv */
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#define SAMPLES_PER_TRAME 240
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#define FREQ_SEP_MIN 5
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#define FREQ_SEP_MAX 15
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#define FREQ_DATA_MIN 15
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#define FREQ_DATA_THRESHOLD 25
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#define FREQ_DATA_MAX 60
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#define THRESHOLD 500
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#define DEBUG 0
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#define FLUSH_TIMEOUT 1
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static signed short trame[2 * SAMPLES_PER_TRAME];
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static signed short pulse[2 * SAMPLES_PER_TRAME];
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static int ringpos = 0;
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static int pos, f1, f2;
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static int amplitude = 0;
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static int lp = 0;
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static void
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read_sample (void)
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{
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amplitude -= abs (trame[ringpos]);
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f1 -= pulse[ringpos];
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f1 += pulse[(ringpos + SAMPLES_PER_TRAME) % (2 * SAMPLES_PER_TRAME)];
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f2 -= pulse[(ringpos + SAMPLES_PER_TRAME) % (2 * SAMPLES_PER_TRAME)];
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fread (trame + ringpos, 1, sizeof (trame[0]), stdin);
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amplitude += abs (trame[ringpos]);
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if (pos ? (trame[ringpos] < -THRESHOLD)
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: (trame[ringpos] > +THRESHOLD))
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{
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pulse[ringpos] = 1;
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pos = !pos;
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f2++;
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}
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else
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pulse[ringpos] = 0;
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ringpos++;
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ringpos %= 2 * SAMPLES_PER_TRAME;
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lp++;
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}
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int
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main ()
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{
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int bitn = 7;
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char c = 0;
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int i;
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int llp = 0;
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while (!feof (stdin))
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{
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if (lp > 3 * SAMPLES_PER_TRAME)
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{
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bitn = 7;
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c = 0;
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lp = 0;
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llp++;
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}
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if (llp == FLUSH_TIMEOUT)
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fflush (stdout);
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if (f2 > FREQ_SEP_MIN && f2 < FREQ_SEP_MAX
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&& f1 > FREQ_DATA_MIN && f1 < FREQ_DATA_MAX)
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{
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#if DEBUG
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printf ("%d %d %d @%d\n", f1, f2, FREQ_DATA_THRESHOLD,
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ftell (stdin) - sizeof (trame));
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#endif
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if (f1 < FREQ_DATA_THRESHOLD)
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c |= (1 << bitn);
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bitn--;
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if (bitn < 0)
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{
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#if DEBUG
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printf ("<%c, %x>", c, c);
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#else
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printf ("%c", c);
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#endif
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bitn = 7;
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c = 0;
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}
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lp = 0;
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llp = 0;
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for (i = 0; i < SAMPLES_PER_TRAME; i++)
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read_sample ();
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continue;
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}
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read_sample ();
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}
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return 0;
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}
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