OutOfMemoryError

glchriste

in Contributed Library Questions • 9 months ago

Quick question! I have tweaked Neil Wallis's Java water simulation to work with input from a WebCam. However, after a few seconds, an OutOfMemoryError occurs. I have tried calling the garbage collector with System.gc(), but it ultimately still crashes. Is there any other way to handle this error? I would love to get this code working.

Code is as follows. To get it to work yourself, you need the gsvideo processing library. You can find it here. http://gsvideo.sourceforge.net/

import java.io.*; // for the loadPatternFilenames() function
import codeanticode.gsvideo.*; // the GSVideo library
GSCapture cam;
PImage img;
int size;
int hwidth,hheight;
int riprad;
int ripplemap[];
int ripple[];
int texture[];
int oldind,newind, mapind;
int i,a,b;
int frameCount;
void setup(){
img = loadImage("background.jpg");
frameCount = 0;
//width = img.width;
//height = img.height;
//size(width, height);
size(1280, 720);
frameRate(40);
cam = new GSCapture(this, 1280, 720);
cam.start();
noStroke();
hwidth = width>>1;
hheight = height>>1;
riprad=5; //test with 3
size = width * (height+2) * 2;
ripplemap = new int[size];
ripple = new int[width*height];
texture = new int[width*height];
oldind = width;
newind = width * (height+3);
image(img, 0, 0);
loadPixels();
smooth();
}
void draw() {
//System.gc();
//Camera
//Get input from the camera.
if (cam.available())
cam.read();
img = cam.get();
//Water Ripples
image(img, 0, 0);
loadPixels();
texture = pixels;
newframe();
for (int i = 0; i < pixels.length; i++) {
pixels[i] = ripple[i];
}
updatePixels();
frameCount++;
if(frameCount%120==0) {
System.gc();
}
}
public void disturb(int dx, int dy) {
//System.gc();
for (int j=dy-riprad;j<dy+riprad;j++) {
for (int k=dx-riprad;k<dx+riprad;k++) {
if (j>=0 && j<height && k>=0 && k<width) {
ripplemap[oldind+(j*width)+k] += 128; //test with 512
}
}
}
}
void newframe() {
//Toggle maps each frame
i=oldind;
oldind=newind;
newind=i;
i=0;
mapind=oldind;
for (int y=0;y<height;y++) {
for (int x=0;x<width;x++) {
short data = (short)((ripplemap[mapind-width]+ripplemap[mapind+width]+ripplemap[mapind-1]+ripplemap[mapind+1])>>1);
data -= ripplemap[newind+i];
data -= data >> 5;
ripplemap[newind+i]=data;
//where data=0 then still, where data>0 then wave
data = (short)(1024-data);
//offsets
a=((x-hwidth)*data/1024)+hwidth;
b=((y-hheight)*data/1024)+hheight;
//bounds check
if (a>=width) a=width-1;
if (a<0) a=0;
if (b>=height) b=height-1;
if (b<0) b=0;
ripple[i]=texture[a+(b*width)];
mapind++;
i++;
}
}
}
//Mouse functions
void mouseDragged()
{
//disturb(mouseX, mouseY);
}
void mouseMoved()
{
disturb(mouseX, mouseY);
}
void mouseReleased()
{
}

Replies(3)

glchriste

Re: OutOfMemoryError

9 months ago

Alright, I found the error and fixed it. The problem was a build up of objects during the draw() loop that the garbage collector wasn't keeping up with. After a new image is created / assigned, call removeCache(img) to clear the cache--no more OOM.

Here is the working code. It's pretty cool!

import java.io.*; // for the loadPatternFilenames() function
import codeanticode.gsvideo.*; // the GSVideo library
GSCapture cam;
PImage img;
int size;
int hwidth,hheight;
int riprad;
int ripplemap[];
int ripple[];
int texture[];
int oldind,newind, mapind;
int i,a,b;
int frameCount;
void setup(){
img = loadImage("background.jpg");
frameCount = 0;
//width = img.width;
//height = img.height;
//size(width, height);
size(1280, 720);
frameRate(40);
cam = new GSCapture(this, 1280, 720);
cam.start();
noStroke();
hwidth = width>>1;
hheight = height>>1;
riprad=5; //test with 3
size = width * (height+2) * 2;
ripplemap = new int[size];
ripple = new int[width*height];
texture = new int[width*height];
oldind = width;
newind = width * (height+3);
image(img, 0, 0);
loadPixels();
smooth();
}
void draw() {
//System.gc();
//Camera
//Get input from the camera.
if (cam.available())
cam.read();
removeCache(img);
frameCount++;
println(frameCount + " " + getCache(img));
img = cam.get();
//Water Ripples
image(img, 0, 0);
loadPixels();
texture = pixels;
newframe();
for (int i = 0; i < pixels.length; i++) {
pixels[i] = ripple[i];
}
updatePixels();
//if(frameCount%1==0) {
System.gc();
//}
frameCount++;
}
public void disturb(int dx, int dy) {
//System.gc();
for (int j=dy-riprad;j<dy+riprad;j++) {
for (int k=dx-riprad;k<dx+riprad;k++) {
if (j>=0 && j<height && k>=0 && k<width) {
ripplemap[oldind+(j*width)+k] += 128; //test with 512
}
}
}
}
void newframe() {
//Toggle maps each frame
i=oldind;
oldind=newind;
newind=i;
i=0;
mapind=oldind;
for (int y=0;y<height;y++) {
for (int x=0;x<width;x++) {
short data = (short)((ripplemap[mapind-width]+ripplemap[mapind+width]+ripplemap[mapind-1]+ripplemap[mapind+1])>>1);
data -= ripplemap[newind+i];
data -= data >> 5;
ripplemap[newind+i]=data;
//where data=0 then still, where data>0 then wave
data = (short)(1024-data);
//offsets
a=((x-hwidth)*data/1024)+hwidth;
b=((y-hheight)*data/1024)+hheight;
//bounds check
if (a>=width) a=width-1;
if (a<0) a=0;
if (b>=height) b=height-1;
if (b<0) b=0;
ripple[i]=texture[a+(b*width)];
mapind++;
i++;
}
}
}
//Try switching between using the disturb method in mousePressed or mouseMoved
void mouseDragged()
{
//disturb(mouseX, mouseY);
}
void mouseMoved()
{
disturb(mouseX, mouseY);
}
void mouseReleased()
{
}

GoToLoop

Re: OutOfMemoryError

9 months ago

Just an info about System.gc();:

That method just nabs the Java's garbage collector.
However, it doesn't mean it's gonna obey it right way.

If hungry memory resources are created faster than the speed of GC can deal with them,
RAM runs out anyways!

You can mark an object for future removal by assigning null to it.
Or assigning a new reference to an object, leaving the old orphan.

int[] a = {5, 6, -2, 4, 0, 9};
a = new int[] {31, 54, -1};

Since there's no variable pointing towards where {5, 6, -2, 4, 0, 9} is located within memory anymore,
that memory block is marked for future removal when GC decides to act.

a = null; or a = b; would render the same killing action for the old previous content of a!

That's all!

glchriste

Re: OutOfMemoryError

9 months ago

Thanks for the info!

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