Jump method is getting stuck

I want to process a video frame by frame, but the jump(float where) method is either just taking ages or stuck in some kind of infinite loop or something like that. I used the Frames.pde example and just tweaked it a little for my needs.
Another problem is that mov.frameRate is -1 most of the time. I think both problems are caused by the fact that the movie just started playing very short before, but I might be wrong.
Am I doing something wrong or is this a bug?
(I also posted this to GitHub)

I just changed very little:

/**
 * Frames 
 * by Andres Colubri. 
 * 
 * Moves through the video one frame at the time by using the
 * arrow keys. It estimates the frame counts using the framerate
 * of the movie file, so it might not be exact in some cases.
 */

import processing.video.*;

Movie mov;
int newFrame = 0;
float framerate = 30;

void setup() {
  size(1920, 1080);
  background(0);
  
  // Load and set the video to play. Setting the video 
  // in play mode is needed so at least one frame is read
  // and we can get duration, size and other information from
  // the video stream. 
  mov = new Movie(this, "video.mp4");
  
  // Pausing the video at the first frame. 
  setFrame(0);
}

void movieEvent(Movie m) {
  m.read();
}

void draw() {
  background(255);
  image(mov, 0, 0, width, height);
  saveFrame("frames/frame" + nf(getFrame(), 3) + ".png");
  fill(127);
  text(getFrame() + " / " + (getLength() - 1), 10, 30);
  newFrame++;
  setFrame(newFrame);
}

int getFrame() {    
  return ceil(mov.time() * 30) - 1;
}

void setFrame(int n) {
  mov.play();

  // The duration of a single frame:
  float frameDuration = 1.0 / framerate;

  // We move to the middle of the frame by adding 0.5:
  float where = (n + 0.5) * frameDuration;

  // Taking into account border effects:
  float diff = mov.duration() - where;
  if (diff < 0) {
    where += diff - 0.25 * frameDuration;
  }
  
  // The Program runs until here
  mov.jump(where);
  // But never executes the following code
  mov.pause();
}  

int getLength() {
  return int(mov.duration() * framerate);
}

@shiffman

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