/* compress.c
** Compressor logic
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include "compress.h"
#ifdef USE_X
#include <X11/Xlib.h>
#include <X11/Xutil.h>
static Display *display;
static Window window;
static Visual *visual;
static int screen;
static GC blackGC, whiteGC, blueGC, yellowGC, dkyellowGC, redGC;
#endif
static int *peaks = NULL;
static int gainCurrent, gainTarget;
static struct {
int show_mon;
int anticlip;
int target;
int gainmax;
int gainsmooth;
int buckets;
} prefs;
#ifdef USE_X
static int mon_init = 0;
#endif
void CompressCfg(int show_mon, int anticlip, int target, int gainmax,
int gainsmooth, int buckets)
{
static int lastsize = 0;
prefs.show_mon = show_mon;
prefs.anticlip = anticlip;
prefs.target = target;
prefs.gainmax = gainmax;
prefs.gainsmooth = gainsmooth;
prefs.buckets = buckets;
/* Allocate the peak structure */
peaks = realloc(peaks, sizeof(int)*prefs.buckets);
if (prefs.buckets > lastsize)
memset(peaks + lastsize, 0, sizeof(int)*(prefs.buckets
- lastsize));
lastsize = prefs.buckets;
#ifdef USE_X
/* Configure the monitor window if needed */
if (show_mon && !mon_init)
{
display = XOpenDisplay(getenv("DISPLAY"));
/* We really shouldn't try to init X if there's no X */
if (!display)
{
fprintf(stderr,
"X not detected; disabling monitor window\n");
show_mon = prefs.show_mon = 0;
}
}
if (show_mon && !mon_init)
{
XGCValues gcv;
XColor col;
gainCurrent = gainTarget = (1 << GAINSHIFT);
screen = DefaultScreen(display);
visual = DefaultVisual(display, screen);
window = XCreateSimpleWindow(display,
RootWindow(display, screen),
0, 0, prefs.buckets, 128 + 8, 0,
BlackPixel(display, screen),
WhitePixel(display, screen));
XStoreName(display, window, "AudioCompress monitor");
gcv.foreground = BlackPixel(display, screen);
blackGC = XCreateGC(display, window, GCForeground, &gcv);
gcv.foreground = WhitePixel(display, screen);
whiteGC = XCreateGC(display, window, GCForeground, &gcv);
col.red = 0;
col.green = 0;
col.blue = 65535;
XAllocColor(display, DefaultColormap(display, screen), &col);
gcv.foreground = col.pixel;
blueGC = XCreateGC(display, window, GCForeground, &gcv);
col.red = 65535;
col.green = 65535;
col.blue = 0;
XAllocColor(display, DefaultColormap(display, screen), &col);
gcv.foreground = col.pixel;
yellowGC = XCreateGC(display, window, GCForeground, &gcv);
col.red = 32767;
col.green = 32767;
col.blue = 0;
XAllocColor(display, DefaultColormap(display, screen), &col);
gcv.foreground = col.pixel;
dkyellowGC = XCreateGC(display, window, GCForeground, &gcv);
col.red = 65535;
col.green = 0;
col.blue = 0;
XAllocColor(display, DefaultColormap(display, screen), &col);
gcv.foreground = col.pixel;
redGC = XCreateGC(display, window, GCForeground, &gcv);
mon_init = 1;
}
if (mon_init)
{
if (show_mon)
XMapWindow(display, window);
else
XUnmapWindow(display, window);
XResizeWindow(display, window, prefs.buckets, 128 + 8);
XFlush(display);
}
#endif
}
void CompressFree(void)
{
#ifdef USE_X
if (mon_init)
{
XFreeGC(display, blackGC);
XFreeGC(display, whiteGC);
XFreeGC(display, blueGC);
XFreeGC(display, yellowGC);
XFreeGC(display, dkyellowGC);
XFreeGC(display, redGC);
XDestroyWindow(display, window);
XCloseDisplay(display);
}
#endif
if (peaks)
free(peaks);
}
void CompressDo(void *data, unsigned int length)
{
int16_t *audio = (int16_t *)data, *ap;
int peak, pos;
int i;
int gr, gf, gn;
static int pn = -1;
#ifdef STATS
static int clip = 0;
#endif
static int clipped = 0;
if (!peaks)
return;
if (pn == -1)
{
for (i = 0; i < prefs.buckets; i++)
peaks[i] = 0;
}
pn = (pn + 1)%prefs.buckets;
#ifdef DEBUG
fprintf(stderr, "modifyNative16(0x%08x, %d)\n",(unsigned int)data,
length);
#endif
/* Determine peak's value and position */
peak = 1;
pos = 0;
#ifdef DEBUG
fprintf(stderr, "finding peak(b=%d)\n", pn);
#endif
ap = audio;
for (i = 0; i < length/2; i++)
{
int val = *ap;
if (val > peak)
{
peak = val;
pos = i;
} else if (-val > peak)
{
peak = -val;
pos = i;
}
ap++;
}
peaks[pn] = peak;
/* Only draw if needed, of course */
#ifdef USE_X
if (prefs.show_mon)
{
/* current amplitude */
XDrawLine(display, window, whiteGC,
pn, 0,
pn,
127 -
(peaks[pn]*gainCurrent >> (GAINSHIFT + 8)));
/* amplification */
XDrawLine(display, window, yellowGC,
pn,
127 - (peaks[pn]*gainCurrent
>> (GAINSHIFT + 8)),
pn, 127);
/* peak */
XDrawLine(display, window, blackGC,
pn, 127 - (peaks[pn] >> 8), pn, 127);
/* clip indicator */
if (clipped)
XDrawLine(display, window, redGC,
(pn + prefs.buckets - 1)%prefs.buckets,
126 - clipped/(length*512),
(pn + prefs.buckets - 1)%prefs.buckets,
127);
clipped = 0;
// target line
//XDrawPoint(display, window, redGC,
// pn, 127 - TARGET/256);
// amplification edge
XDrawLine(display, window, dkyellowGC,
pn,
127 - (peaks[pn]*gainCurrent
>> (GAINSHIFT + 8)),
pn - 1,
127 -
(peaks[(pn + prefs.buckets
- 1)%prefs.buckets]*gainCurrent
>> (GAINSHIFT + 8)));
}
#endif
for (i = 0; i < prefs.buckets; i++)
{
if (peaks[i] > peak)
{
peak = peaks[i];
pos = 0;
}
}
/* Determine target gain */
gn = (1 << GAINSHIFT)*prefs.target/peak;
if (gn <(1 << GAINSHIFT))
gn = 1 << GAINSHIFT;
gainTarget = (gainTarget *((1 << prefs.gainsmooth) - 1) + gn)
>> prefs.gainsmooth;
/* Give it an extra insignifigant nudge to counteract possible
** rounding error
*/
if (gn < gainTarget)
gainTarget--;
else if (gn > gainTarget)
gainTarget++;
if (gainTarget > prefs.gainmax << GAINSHIFT)
gainTarget = prefs.gainmax << GAINSHIFT;
#ifdef USE_X
if (prefs.show_mon)
{
int x;
/* peak*gain */
XDrawPoint(display, window, redGC,
pn,
127 - (peak*gainCurrent
>> (GAINSHIFT + 8)));
// gain indicator
XFillRectangle(display, window, whiteGC, 0, 128,
prefs.buckets, 8);
x = (gainTarget - (1 << GAINSHIFT))*prefs.buckets
/ ((prefs.gainmax - 1) << GAINSHIFT);
XDrawLine(display, window, redGC, x,
128, x, 128 + 8);
x = (gn - (1 << GAINSHIFT))*prefs.buckets
/ ((prefs.gainmax - 1) << GAINSHIFT);
XDrawLine(display, window, blackGC,
x, 132 - 1,
x, 132 + 1);
// blue peak line
XDrawLine(display, window, blueGC,
0, 127 - (peak >> 8), prefs.buckets,
127 - (peak >> 8));
XFlush(display);
XDrawLine(display, window, whiteGC,
0, 127 - (peak >> 8), prefs.buckets,
127 - (peak >> 8));
}
#endif
/* See if a peak is going to clip */
gn = (1 << GAINSHIFT)*32768/peak;
if (gn < gainTarget)
{
gainTarget = gn;
if (prefs.anticlip)
pos = 0;
} else
{
/* We're ramping up, so draw it out over the whole frame */
pos = length;
}
/* Determine gain rate necessary to make target */
if (!pos)
pos = 1;
gr = ((gainTarget - gainCurrent) << 16)/pos;
/* Do the shiznit */
gf = gainCurrent << 16;
#ifdef STATS
fprintf(stderr, "\rgain = %2.2f%+.2e ",
gainCurrent*1.0/(1 << GAINSHIFT),
(gainTarget - gainCurrent)*1.0/(1 << GAINSHIFT));
#endif
ap = audio;
for (i = 0; i < length/2; i++)
{
int sample;
/* Interpolate the gain */
gainCurrent = gf >> 16;
if (i < pos)
gf += gr;
else if (i == pos)
gf = gainTarget << 16;
/* Amplify */
sample = (*ap)*gainCurrent >> GAINSHIFT;
if (sample < -32768)
{
#ifdef STATS
clip++;
#endif
clipped += -32768 - sample;
sample = -32768;
} else if (sample > 32767)
{
#ifdef STATS
clip++;
#endif
clipped += sample - 32767;
sample = 32767;
}
*ap++ = sample;
}
#ifdef STATS
fprintf(stderr, "clip %d b%-3d ", clip, pn);
#endif
#ifdef DEBUG
fprintf(stderr, "\ndone\n");
#endif
}
