gstreamer/gst/monoscope/monoscope.c
Richard Boulton b62e08de6e Fix monoscope: caps already asked for mono input: make it actually expect such input.
Original commit message from CVS:
Fix monoscope: caps already asked for mono input: make it actually expect
such input.
2002-03-03 17:29:59 +00:00

137 lines
3.4 KiB
C

/* monoscope.cpp
* Copyright (C) 2002 Richard Boulton <richard@tartarus.org>
* Copyright (C) 1998-2001 Andy Lo A Foe <andy@alsaplayer.org>
* Original code by Tinic Uro
*
* This code is copied from Alsaplayer.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "monoscope.h"
#include "convolve.h"
#define scope_width 256
#define scope_height 128
static gint16 copyEq[CONVOLVE_BIG];
static int avgEq[CONVOLVE_SMALL]; // a running average of the last few.
static int avgMax; // running average of max sample.
static guint32 display[(scope_width + 1) * (scope_height + 1)];
static convolve_state *state = NULL;
static guint32 colors[64];
static void colors_init(guint32 * colors)
{
int i;
for (i = 0; i < 32; i++) {
colors[i] = (i*8 << 16) + (255 << 8);
colors[i+31] = (255 << 16) + (((31 - i) * 8) << 8);
}
colors[63] = (40 << 16) + (75 << 8);
}
void monoscope_init (guint32 resx, guint32 resy)
{
state = convolve_init();
colors_init(colors);
}
guint32 * monoscope_update (gint16 data [512])
{
/* Note that CONVOLVE_BIG must == data size here, ie 512. */
/* Really, we want samples evenly spread over the available data.
* Just taking a continuous chunk will do for now, though. */
int i;
int foo;
int bar;
int h;
guint32 *loc;
int factor;
int val;
int max = 1;
short * thisEq;
memcpy (copyEq, data, sizeof (short) * CONVOLVE_BIG);
thisEq = copyEq;
#if 1
val = convolve_match (avgEq, copyEq, state);
thisEq += val;
#endif
memset(display, 0, 256 * 128 * sizeof(guint32));
for (i=0; i < 256; i++) {
foo = thisEq[i] + (avgEq[i] >> 1);
avgEq[i] = foo;
if (foo < 0)
foo = -foo;
if (foo > max)
max = foo;
}
avgMax += max - (avgMax >> 8);
if (avgMax < max)
avgMax = max; /* Avoid overflow */
factor = 0x7fffffff / avgMax;
/* Keep the scaling sensible. */
if (factor > (1 << 18))
factor = 1 << 18;
if (factor < (1 << 8))
factor = 1 << 8;
for (i=0; i < 256; i++) {
foo = avgEq[i] * factor;
foo >>= 18;
if (foo > 63)
foo = 63;
if (foo < -64)
foo = -64;
val = (i + ((foo+64) << 8));
bar = val;
if ((bar > 0) && (bar < (256 * 128))) {
loc = display + bar;
if (foo < 0) {
for (h = 0; h <= (-foo); h++) {
*loc = colors[h];
loc+=256;
}
} else {
for (h = 0; h <= foo; h++) {
*loc = colors[h];
loc-=256;
}
}
}
}
/* Draw grid. */
for (i=16;i < 128; i+=16) {
for (h = 0; h < 256; h+=2) {
display[(i << 8) + h] = colors[63];
if (i == 64)
display[(i << 8) + h + 1] = colors[63];
}
}
for (i = 16; i < 256; i+=16) {
for (h = 0; h < 128; h+=2) {
display[i + (h << 8)] = colors[63];
}
}
return display;
}
void monoscope_close ()
{
}