pixel flipper, data sifter. trying to see what I can while I'm here
K = {
let context, canvas, scale = width / N;
if (this && this.getContext) {
canvas = this;
context = canvas.getContext("2d");
context.clearRect(0, 0, N * scale, HN * scale);
} else {
context = DOM.context2d(N * scale, HN * scale, 1);
canvas = context.canvas;
canvas.style.background = "#333";
canvas.style.width = `${scale * N}px`;
canvas.style.height = `${scale * HN}px`;
}
let path = d3.geoPath(d3.geoIdentity().scale(scale)).context(context);
let l = imageData.data.length / 4,
a = new Uint8Array(l);
for (let i = 0; i < l; i+=1)
a[i] = 1/3 * (imageData.data[i*4 + 0] + imageData.data[i*4 + 1] + imageData.data[i*4 + 2])
contours(a).forEach(c => {
context.beginPath(),
path(c),
context.fillStyle = d3.interpolateRdYlBu(c.value/256),
context.fill(),
context.strokeStyle = 'white',
context.stroke();
});
return canvas;
}
image = {
if (enableWebcam) {
let deviceId = devices.filter(function(d) {
return d.label == videoSource
}).map(function(d) { return d.deviceId })[0]
let constraints = {
video: {deviceId: {exact: deviceId}}
}
const stream = navigator.mediaDevices
? navigator.mediaDevices.getUserMedia(constraints)
: new Promise((y, n) => navigator.getUserMedia(constraints, y, n));
const video = html`<video autoplay=true playsinline=true width="${width}"></video>`;
video.style.maxWidth = "100%";
yield stream.then(stream => {
if ("srcObject" in video) video.srcObject = stream;
else video.src = URL.createObjectURL(stream);
invalidation.then(() => {
stream.getTracks().forEach(t => t.stop());
URL.revokeObjectURL(video.src);
});
return video;
});
while (true) {
yield video;
}
} else {
yield image2canvas(await getImageData(filepic), width)
}
// else {
// yield new Promise((resolve, reject) => {
// const image = new Image;
// image.onload = () => resolve(image);
// image.onerror = reject;
// image.crossOrigin = "anonymous";
// image.src = url;
// });
// }
}
devices = navigator.mediaDevices.enumerateDevices()
videoDevices = devices.filter(d => d.kind == "videoinput")
imageData = {
const width = N, height = HN;
const context = this ? this.context : DOM.context2d(width, height, 1);
context.drawImage(image, 0, 0, width, height);
const data = context.getImageData(0, 0, width, height);
data.context = context;
return data;
}
width
image.videoWidth
height = {
if(image.videoWidth) {
return image.videoHeight * width / image.videoWidth
}
return image.height * width / image.width
}
N = 224
HN = Math.round(N * height / image.width)
d3 = require("d3@6")
contours = d3.contours().thresholds(thresholds).size([imageData.width, imageData.height])
import {checkbox, slider, select} from "@jashkenas/inputs"
import {fileInput} from "@mbostock/file-input-with-initial-value"
async function getImageData(blob) {
let img = new Image();
img.crossOrigin = '*';
img.src = URL.createObjectURL(blob);
await new Promise(resolve => img.addEventListener('load', resolve));
let w = img.width
let h = img.height
let ctx = DOM.canvas(w, h).getContext('2d');
ctx.drawImage(img, 0, 0, w, h);
return ctx.getImageData(0, 0, w, h);
}
image2canvas = (imageData, width) => {
const context = DOM.context2d(imageData.width, imageData.height, 1);
context.putImageData(imageData, 0, 0);
if (!width || imageData.width <= width) return context.canvas;
const height = (imageData.height * width) / imageData.width;
const contextr = DOM.context2d(width, height, 1);
contextr.drawImage(context.canvas, 0, 0, width, height);
return contextr.canvas;
}
One platform to build and deploy the best data apps
Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.