removal.ai [ai] [background removal]

/*
base        : https://removal.ai/
by          : wolep
nama        : ai background removal
fungsi      : buat remove background (iya iyalah)
last update : 13 Juli 2025, 8:30 WITA
note        : lu cuma perlu buffer image input, no denpendency install,
              panggil function removal.removeBackground terus masukin
              buffer image lu disana, return nya lu cuma di kasih resolusi
              preview, kalau mau full resolusi lu musit bayar di situs nya :v
              btw liat cara pakai di bawah :v

*/

const removal = {
    // fetch boilerplate lol
    _hit: async (url, fetchName = "lu lupa isi fetch name", returnType = "text", opts = {}) => {
        const r = await fetch(url, opts)
        if (!r.ok) throw Error(`fetch fail\n${r.status} ${r.statusText}\nat: ${fetchName}\nnih text nya: ${await r.text() || null}`)
        try {
            if (returnType == "json") return await r.json()
            return await r.text()
        } catch (err) {
            throw Error(`fetch berhasil tapi gagal convert ke json\n${err.message}\nat: ${fetchName}\nnih text nya :${await r.text() || null}`)
        }
    },

    // function buat bikin formdata gw hardcode >:v
    _formData: (imageBuffer) => {
        const randomBoundary = "----WebKitFormBoundary" + Math.random().toString(32).slice(2)
        const buffers = []
        buffers.push(Buffer.from("--" + randomBoundary + "\r\nContent-Disposition: form-data; name=\"image_file\"; filename=\"Untitled-1_magicstudio_" + Math.random().toString(32).slice(2) + ".png\"\r\nContent-Type: image/png\r\n\r\n"))
        buffers.push(imageBuffer)
        buffers.push(Buffer.from("\r\n--" + randomBoundary + "--\r\n"))
        const body = Buffer.concat(buffers)
        const formDataHeaders = { "content-type": "multipart/form-data; boundary=" + randomBoundary }
        return { formDataHeaders, body }
    },

    // function buat dapetin web token, kalau berhasil bakalan return string kayak b42622b7fe912a89fd27646476fe4eab
    getWebToken: async () => {
        // fetch home page
        const html = await removal._hit("https://removal.ai/", "hit homepage")
        const match = html.match(/var ajax_upload_object = (.*?);/)?.[1]
        if (!match) throw Error(`tidak menemukan match pada homepage`)
        const { webtoken_url, security } = JSON.parse(match)

        // second fetch to get Web-Token
        const webTokenUrl = `${webtoken_url}?action=ajax_get_webtoken&security=${security}`
        const json = await removal._hit(webTokenUrl, "mendapatkan web token", "json")
        const webToken = json?.data?.webtoken
        if (!webToken) throw Error(`berhasil hit url web token tapi gak ada token nya`)
        return webToken
    },

    // main function
    removeBackground: async (imageBuffer) => {

        const { formDataHeaders, body } = removal._formData(imageBuffer)

        const headers = {
            "web-token": await removal.getWebToken(),
            ...formDataHeaders
        }

        const opts = {
            headers,
            body,
            "method": "POST"
        }

        const result = await removal._hit("https://api.removal.ai/3.0/remove", "remove background", "json", opts)
        return result
    }
}

// cara pakai
const buffer = require("fs").readFileSync("./gambar2.jpg")
removal.removeBackground(buffer)
    .then(console.log)
    .catch(err => console.log(err.message))

/* output
{
  status: 200,
  demo: null,
  base64: null,
  original_width: 1059,
  original_height: 1200,
  preview_width: 529,
  preview_height: 600,
  extra: null,
  url: 'https://api.removal.ai/download/g1/preview/5e0c8353-c9e0-46fe-a07d-75044d30ecec.png',
  high_resolution: null,
  low_resolution: 'https://api.removal.ai/download/g1/preview/5e0c8353-c9e0-46fe-a07d-75044d30ecec.png',
  preview_demo: 'https://api.removal.ai/download/g1/preview/5e0c8353-c9e0-46fe-a07d-75044d30ecec.png',
  original: 'https://api.removal.ai/uploads/guest/182.253.149.185/d62842dd-57a0-4ff5-a085-21630ea7f1f0-untitled-1_magicstudio_03ogk93tkc.png'
}
*/