Video scrubbing seems choppy

#1

howdy folks,

im currently working on new tutorials but wanted to go back to video scrubbing. but there is some problems I seem to have compared to what was happening prior [which worked fully well] in the previous one I done 4+ years ago. im also making it better in general & updating things.

all that I am using is an ofParameter & ofxGui that is playing with the setFrame of a video from the ofVideoPlayer. really simple stuff. but currently it seems to be as choppy as a chopper in a chop shop.

it doesn’t smoothly scrub thru the video like before, but instead jumps to certain points, rather than go thru the frames

this is on macOS using latest public Mojave OS

ofApp.h

#include "ofxGui.h"

ofVideoGrabber video;

ofxPanel gui;
ofxParameter<int> scrub>;

ofApp.cpp

void ofApp::setup(){
  video.load("video.mp4");

  gui.setup();
  gui.add(scrub.set("scrub", 0, 0, video.getTotalNumFrames()));
}

void ofApp::update(){
  video.setFrame(scrub);
}

void ofApp::draw(){
  video.draw(0, 0);
  
  gui.draw();
}
#2

it depends a lot on the codec you are using, since most videos are encodec now to have one keyframe each 24 frames. the best option is a non-multiframe codec as photojpeg.
better yet would be using Arturo ofxGstreamer (more performing than ofVideoPlayer), but if you need total immediate performing video scrubbing I think using a video player is not a good option at all.
cheers