ref: b6faa22c951f34b6b1c3d983b475c183069cf2ed
parent: abed578324ce19ac81024f2aeb1b5dea8dc74e17
author: cbagwell <cbagwell>
date: Mon Sep 13 19:32:49 EDT 2004
Fix MIN overflow in volume change.
--- a/Changelog
+++ b/Changelog
@@ -36,6 +36,12 @@
audio files and do a crossfade between them.
o Fixed bug in fade effect were it was impossible to do a
fadeout starting from the beginning of the audio file.
+ o Removed rounding error when changing volume of audio with
+ "-v" option. This error caused doing a "-v -1.0" twice
+ to not result in the original file.
+ o Fixed bug in volume changes (both -v and "vol" effect)
+ were an overflow could occur on the negative side
+ because it wasn't accounting for MIN being (-MAX)-1.
sox-12.17.5
-----------
--- a/src/vol.c
+++ b/src/vol.c
@@ -21,10 +21,10 @@
/* constants
*/
-#define ZERO ((VOL_FLOAT)(0.0e0))
+#define ZERO ((VOL_FLOAT)(0.0e0))
#define LOG_10_20 ((VOL_FLOAT)(0.1151292546497022842009e0))
-#define ONE ((VOL_FLOAT)(1.0e0))
-#define TWENTY ((VOL_FLOAT)(20.0e0))
+#define ONE ((VOL_FLOAT)(1.0e0))
+#define TWENTY ((VOL_FLOAT)(20.0e0))
#define VOL_USAGE \
"Usage: vol gain [ type [ limitergain ] ]" \
@@ -56,50 +56,50 @@
if (n && (!sscanf(argv[0], VOL_FLOAT_SCAN, &vol->gain)))
{- st_fail(VOL_USAGE);
- return ST_EOF;
+ st_fail(VOL_USAGE);
+ return ST_EOF;
}
/* adjust gain depending on type (what a great parser;-) */
if (n>1)
{- switch (argv[1][0])
- {- case 'd': /* decibels to amplitude */
- case 'D':
- vol->gain = exp(vol->gain*LOG_10_20);
- break;
- case 'p':
- case 'P': /* power to amplitude, keep phase change */
- if (vol->gain > ZERO)
- vol->gain = sqrt(vol->gain);
- else
- vol->gain = -sqrt(-vol->gain);
- break;
- case 'a': /* amplitude */
- case 'A':
- default:
- break;
- }
+ switch (argv[1][0])
+ {+ case 'd': /* decibels to amplitude */
+ case 'D':
+ vol->gain = exp(vol->gain*LOG_10_20);
+ break;
+ case 'p':
+ case 'P': /* power to amplitude, keep phase change */
+ if (vol->gain > ZERO)
+ vol->gain = sqrt(vol->gain);
+ else
+ vol->gain = -sqrt(-vol->gain);
+ break;
+ case 'a': /* amplitude */
+ case 'A':
+ default:
+ break;
+ }
}
if (n>2)
{- if ((fabs(vol->gain) < ONE) || !sscanf(argv[2], VOL_FLOAT_SCAN, &vol->limitergain) || !((vol->limitergain > ZERO) && (vol->limitergain < ONE)))
- {- st_fail(VOL_USAGE);
- return ST_EOF;
- }
-
- vol->uselimiter = 1; /* ok, we'll use it */
- /* The following equation is derived so that there is no
- * discontinuity in output amplitudes */
- /* and a ST_SAMPLE_MAX input always maps to a ST_SAMPLE_MAX output
- * when the limiter is activated. */
- /* (NOTE: There **WILL** be a discontinuity in the slope
- * of the output amplitudes when using the limiter.) */
- vol->limiterthreshhold = ST_SAMPLE_MAX * (ONE - vol->limitergain) / (fabs(vol->gain) - vol->limitergain);
+ if ((fabs(vol->gain) < ONE) || !sscanf(argv[2], VOL_FLOAT_SCAN, &vol->limitergain) || !((vol->limitergain > ZERO) && (vol->limitergain < ONE)))
+ {+ st_fail(VOL_USAGE);
+ return ST_EOF;
+ }
+
+ vol->uselimiter = 1; /* ok, we'll use it */
+ /* The following equation is derived so that there is no
+ * discontinuity in output amplitudes */
+ /* and a ST_SAMPLE_MAX input always maps to a ST_SAMPLE_MAX output
+ * when the limiter is activated. */
+ /* (NOTE: There **WILL** be a discontinuity in the slope
+ * of the output amplitudes when using the limiter.) */
+ vol->limiterthreshhold = ST_SAMPLE_MAX * (ONE - vol->limitergain) / (fabs(vol->gain) - vol->limitergain);
}
@@ -115,15 +115,15 @@
if (effp->outinfo.channels != effp->ininfo.channels)
{- st_warn("VOL cannot handle different channels (in=%d, out=%d)"- " use avg or pan", effp->ininfo.channels, effp->outinfo.channels);
+ st_warn("VOL cannot handle different channels (in=%d, out=%d)"+ " use avg or pan", effp->ininfo.channels, effp->outinfo.channels);
}
if (effp->outinfo.rate != effp->ininfo.rate)
{- st_fail("VOL cannot handle different rates (in=%ld, out=%ld)"- " use resample or rate", effp->ininfo.rate, effp->outinfo.rate);
- return ST_EOF;
+ st_fail("VOL cannot handle different rates (in=%ld, out=%ld)"+ " use resample or rate", effp->ininfo.rate, effp->outinfo.rate);
+ return ST_EOF;
}
vol->clipped = 0;
@@ -141,13 +141,13 @@
{if (v > ST_SAMPLE_MAX)
{- vol->clipped++;
- return ST_SAMPLE_MAX;
+ vol->clipped++;
+ return ST_SAMPLE_MAX;
}
- else if (v < -ST_SAMPLE_MAX)
+ else if (v < ST_SAMPLE_MIN)
{- vol->clipped++;
- return -ST_SAMPLE_MAX;
+ vol->clipped++;
+ return ST_SAMPLE_MIN;
}
/* else */
return (st_sample_t) v;
@@ -176,35 +176,41 @@
if (vol->uselimiter)
{- vol->totalprocessed += len;
-
- for (;len>0; len--)
- {- sample = *ibuf++;
-
- if (sample > limiterthreshhold)
- {- sample = (ST_SAMPLE_MAX - vol->limitergain * (ST_SAMPLE_MAX - sample));
- vol->limited++;
- }
- else if (sample < -limiterthreshhold)
- {- sample = -(ST_SAMPLE_MAX - vol->limitergain * (ST_SAMPLE_MAX + sample));
- vol->limited++;
- }
- else
- {- sample = gain * sample;
- }
-
- *obuf++ = clip(vol, sample);
- }
+ vol->totalprocessed += len;
+
+ for (;len>0; len--)
+ {+ sample = *ibuf++;
+
+ if (sample > limiterthreshhold)
+ {+ sample = (ST_SAMPLE_MAX - vol->limitergain * (ST_SAMPLE_MAX - sample));
+ vol->limited++;
+ }
+ else if (sample < -limiterthreshhold)
+ {+ sample = -(ST_SAMPLE_MAX - vol->limitergain * (ST_SAMPLE_MAX + sample));
+ /* FIXME: MIN is (-MAX)-1 so need to make sure we
+ * don't go over that. Probably could do this
+ * check inside the above equation but I didn't
+ * think it thru.
+ */
+ if (sample < ST_SAMPLE_MIN)
+ sample = ST_SAMPLE_MIN;
+ vol->limited++;
+ } else
+ {+ sample = gain * sample;
+ }
+
+ *obuf++ = clip(vol, sample);
+ }
}
else
{- /* quite basic, with clipping */
- for (;len>0; len--)
- *obuf++ = clip(vol, gain * *ibuf++);
+ /* quite basic, with clipping */
+ for (;len>0; len--)
+ *obuf++ = clip(vol, gain * *ibuf++);
}
return ST_SUCCESS;
}
@@ -218,13 +224,13 @@
vol_t vol = (vol_t) effp->priv;
if (vol->limited)
{- st_warn("VOL limited %d values (%d percent).", - vol->limited, (int) (vol->limited * 100.0 / vol->totalprocessed));
+ st_warn("VOL limited %d values (%d percent).", + vol->limited, (int) (vol->limited * 100.0 / vol->totalprocessed));
}
if (vol->clipped)
{- st_warn("VOL clipped %d values, amplitude gain=%f too high...", - vol->clipped, vol->gain);
+ st_warn("VOL clipped %d values, amplitude gain=%f too high...", + vol->clipped, vol->gain);
}
return ST_SUCCESS;
}