Error about the size of a video for cv.read // openCV.js

1

Hello there !

I’m trying to record a video from cam in browser, stop the recording, then to apply an Edge Detection Filter to the recorded video.
Recording is done by a function working with WebRTC. This function provide me a blob blobVideoColor and an URL to this blob URLvideoColor.
My issue is while treating the video.

Here is the code I’m working on :

<video src="" id="videoTempTreatment"> </video>

var matSrc = new cv.Mat(hauteur, largeur, cv.CV_8UC4);
var matDst = new cv.Mat(hauteur, largeur, cv.CV_8UC1);
var captur = new cv.VideoCapture(traitement);
//... Some code for recording, useless here.
function treatmentInit(){
    video = document.getElementById("videoTempTreatment");
    video.src = URLvideoColor; // Affecting blob to html <video>
    video.addEventListener("loadeddata", startTreatment); // Waiting for the blob to be into the <video>
}

function startTreatment(){
    //Initializing mat's and capture object
    const hauteur = video.videoHeight;
    const largeur = video.videoWidth;

    matSrc = new cv.Mat(hauteur, largeur, cv.CV_8UC4);
    matDst = new cv.Mat(hauteur, largeur, cv.CV_8UC1);
    captur = new cv.VideoCapture(video);

    let dooku = 1; // T'as compris la blague ?
    video.play();
    video.addEventListener("play",  edgeVideo(dooku); // Just in case my issue was due to the video not playing ?
}

function edgeVideo(count){
    // Some verifications on sizes
    console.log("matSrc.cols*rows : %o * %o", matSrc.cols, matSrc.rows);
    console.log("video.width*height : %o*%o", video.videoHeight, video.videoWidth;
    //As expected, matSrc and video have same dimensions, not the issue origin.

    captur.read(matSrc);
    // treatment on frame, but read don't works properly...
}

My issue is with the captur.read(matSrc); line, at the end of the code I’m providing. There is an error :

Uncaught Error: Bad size of input mat: the size should be same as the video.

There is why I verified the sizes of video and matSrc so it’s not the issue.
I don’t think the issue come from my recorded video too, cause it’s played properly. but just to be sure, I modified my code to use a local video :
The line

    video.src = URLvideoColor; // Affecting blob to html <video>

was deleted in js, and I modified the html to add a local src :

<video src="ressources/neige.webm" id="videoTempTreatment"> </video>

Once again, the video is playing properly, but I’ve the same error, except for one detail :

Uncaught (in promise) Error: Bad size of input mat: the size should be same as the video.

Why is it talking about a promise ? according to datasheet, neither cv.src()nor cv.VideoCapture(video) are returning a promise… Maybe this answer about the promise with local video can help me with the recorded video.

“any clue will be apreciated”