Draw image from pixel array on canvas with putImageData

arrays, canvas, javascript, pixel, putimagedata

Solution

Assuming `imgd` is simply an Array containing all byte values, you still need to convert the array to ImageData.

var imgd = [27,32,26,28,33,27,30,35,29,31.....]

// first, create a new ImageData to contain our pixels
var imgData = ctx.createImageData(160, 120); // width x height
var data = imgData.data;

// copy img byte-per-byte into our ImageData
for (var i = 0, len = 160 * 120 * 4; i < len; i++) {
    data[i] = imgd[i];
}

// now we can draw our imagedata onto the canvas
ctx.putImageData(imgData, 0, 0);

Problem

I am working on a project that can encrypt an image and redraw the decrypted image on canvas. As I am still pretty new to coding and programming, I am currently having issues redrawing the decrypted image data, which is a pixel array in the form R,G,B,A. I thought this would be possible by simply putting the data into ``` ctx.putImageData(imgd,0,0); ``` But firebug tells me that the value does not implement the interface for imagedata. I have posted the entire array here. The image is 160px wide and 120px high. Is there any way to reformat the array so that it is drawable on the canvas?

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