gstreamer/subprojects/gst-plugins-good/gst/monoscope/monoscope.c

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/* 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
*
2019-09-02 12:27:35 +00:00
* This code is copied from Alsaplayer. The original code was by Tinic Uro and under
* the BSD license without a advertisig clause. Andy Lo A Foe then relicensed the
* code when he used it for Alsaplayer to GPL with Tinic's permission. Richard Boulton
* then took this code and made a GPL plugin out of it.
*
* 7th December 2004 Christian Schaller: Richard Boulton and Andy Lo A Foe gave
* permission to relicense their changes under BSD license so we where able to restore the
* code to Tinic's original BSD license.
*
* This file is under what is known as the BSD license:
*
* Redistribution and use in source and binary forms, with or without modification, i
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
* WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "monoscope.h"
#include <string.h>
#include <stdlib.h>
static void
colors_init (guint32 * colors)
{
int i;
int hq = (scope_height / 4);
int hq1 = hq - 1;
int hh1 = (scope_height / 2) - 1;
double scl = (256.0 / (double) hq);
for (i = 0; i < hq; i++) {
/* green to yellow */
colors[i] = ((int) (i * scl) << 16) + (255 << 8);
/* yellow to red */
colors[i + hq1] = (255 << 16) + ((int) ((hq1 - i) * scl) << 8);
}
colors[hh1] = (40 << 16) + (75 << 8);
}
struct monoscope_state *
monoscope_init (guint32 resx, guint32 resy)
{
struct monoscope_state *stateptr;
/* I didn't program monoscope to only do 256*128, but it works that way */
g_return_val_if_fail (resx == scope_width, 0);
g_return_val_if_fail (resy == scope_height, 0);
stateptr = calloc (1, sizeof (struct monoscope_state));
if (stateptr == 0)
return 0;
stateptr->cstate = convolve_init (convolver_depth);
colors_init (stateptr->colors);
return stateptr;
}
void
monoscope_close (struct monoscope_state *stateptr)
{
convolve_close (stateptr->cstate);
free (stateptr);
}
guint32 *
monoscope_update (struct monoscope_state *stateptr, gint16 data[convolver_big])
{
/* Really, we want samples evenly spread over the available data.
* Just taking a continuous chunk will do for now, though. */
int i;
int foo, bar;
int avg;
int h;
int hh = (scope_height / 2);
int hh1 = hh - 1;
guint32 *loc;
double factor;
int max = 1;
short *thisEq = stateptr->copyEq;
memcpy (thisEq, data, sizeof (short) * convolver_big);
thisEq += convolve_match (stateptr->avgEq, thisEq, stateptr->cstate);
memset (stateptr->display, 0, scope_width * scope_height * sizeof (guint32));
for (i = 0; i < convolver_small; i++) {
avg = (thisEq[i] + stateptr->avgEq[i]) >> 1;
stateptr->avgEq[i] = avg;
avg = abs (avg);
max = MAX (max, avg);
}
/* running average, 4 values is enough to make it follow volume changes
* if this value is too large it will converge slowly
*/
stateptr->avgMax += (max / 4) - (stateptr->avgMax / 4);
/* input is +/- avgMax, output is +/- hh */
if (stateptr->avgMax) {
factor = (gdouble) hh / stateptr->avgMax;
} else {
factor = 1.0;
}
for (i = 0; i < scope_width; i++) {
/* scale 16bit signed audio values to scope_height */
foo = stateptr->avgEq[i] * factor;
foo = CLAMP (foo, -hh1, hh1);
bar = (i + ((foo + hh) * scope_width));
if ((bar > 0) && (bar < (scope_width * scope_height))) {
loc = stateptr->display + bar;
/* draw up / down bars */
if (foo < 0) {
for (h = 0; h <= (-foo); h++) {
*loc = stateptr->colors[h];
loc += scope_width;
}
} else {
for (h = 0; h <= foo; h++) {
*loc = stateptr->colors[h];
loc -= scope_width;
}
}
}
}
/* Draw grid. */
{
guint32 gray = stateptr->colors[hh1];
for (i = 16; i < scope_height; i += 16) {
for (h = 0; h < scope_width; h += 2) {
stateptr->display[(i * scope_width) + h] = gray;
if (i == hh)
stateptr->display[(i * scope_width) + h + 1] = gray;
}
}
for (i = 16; i < scope_width; i += 16) {
for (h = 0; h < scope_height; h += 2) {
stateptr->display[i + (h * scope_width)] = gray;
}
}
}
return stateptr->display;
}