ofAVFoundationPlayer — ofVideoPlayer - ideas?

extend
#1

I’m now taking a look on ofAVFoundationPlayer just to learn a little bit more about ofVideoPlayer internals.

I’ve noticed two of the things that happens the first time a video is loaded are

ofAVFoundationVideoPlayer alloc
CVOpenGLTextureCacheCreate

And they are not called anymore when I load the same video the second time, or a different video in the same ofVideoPlayer object.
Question: any of this objects should be recreated in the case I load some video with different pixel dimensions from the first video?

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Other thing I’ve noticed is initTextureCache() is being called every frame, so maybe we could avoid allocating a new texture every frame with the following:

    if (!videoTexture.isAllocated()) {
        int videoTextureW = getWidth();
        int videoTextureH = getHeight();
        videoTexture.allocate(videoTextureW, videoTextureH, GL_RGBA);
    }

but probably had to ofTexture::clear after loading a different video. or better yet, after detecting we loaded a different video with different dimensions.

#2

I’ve made a quick test of a program that can load two different videos in the same videoplayer instance, like this

#include "ofApp.h"

void ofApp::setup(){
    video.load("v.mov");
    video.play();
}

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

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

void ofApp::keyPressed(int key) {
	// ofLog("xaza");
    if (key == 'q') {
        video.load("v.mov");
        video.play();
    }
    if (key == 'w') {
        video.load("v2.mov");
        video.play();
    }
}

And I think each load is spawning a new thread, and new ones when video loops and get back to start position. with a quick test of a few minutes I could see more than 100 threads

Screen Shot 2021-11-23 at 22.30.05
Screen Shot 2021-11-23 at 22.30.051940×1402 312 KB

#3

wow. do you think that it is AVFoundation that does that or that its implementation within OF is wrong?

#4

My guess is there is something specific to OF.
Maybe related, title is maybe misleading:

Trying to look at
dispatch_async and dispatch_queue_t used inside ofAVFoundationVideoPlayer.m
both for load and loadAsync

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