[Wasm] BLIP Example (#1183)

* blip wasm start

* fix dependency issue, move token stream here

* vanilla js worker

* roll back vscode

* spell

candle-wasm-examples/blip/blipWorker.js

@@ -0,0 +1,77 @@
+import init, { Model } from "./build/m.js";
+
+async function fetchArrayBuffer(url, cacheFile = true) {
+  if (!cacheFile) return new Uint8Array(await (await fetch(url)).arrayBuffer());
+  const cacheName = "blip-candle-cache";
+  const cache = await caches.open(cacheName);
+  const cachedResponse = await cache.match(url);
+  if (cachedResponse) {
+    const data = await cachedResponse.arrayBuffer();
+    return new Uint8Array(data);
+  }
+  const res = await fetch(url, { cache: "force-cache" });
+  cache.put(url, res.clone());
+  return new Uint8Array(await res.arrayBuffer());
+}
+class Blip {
+  static instance = {};
+
+  static async getInstance(
+    weightsURL,
+    tokenizerURL,
+    configURL,
+    modelID,
+    quantized
+  ) {
+    if (!this.instance[modelID]) {
+      await init();
+
+      self.postMessage({ status: "loading", message: "Loading Model" });
+      const [weightsArrayU8, tokenizerArrayU8, configArrayU8] =
+        await Promise.all([
+          fetchArrayBuffer(weightsURL),
+          fetchArrayBuffer(tokenizerURL),
+          fetchArrayBuffer(configURL),
+        ]);
+
+      this.instance[modelID] = new Model(
+        weightsArrayU8,
+        tokenizerArrayU8,
+        configArrayU8,
+        quantized
+      );
+    } else {
+      self.postMessage({ status: "ready", message: "Model Already Loaded" });
+    }
+    return this.instance[modelID];
+  }
+}
+
+self.addEventListener("message", async (event) => {
+  const { weightsURL, tokenizerURL, configURL, modelID, imageURL, quantized } =
+    event.data;
+  try {
+    self.postMessage({ status: "status", message: "Loading Blip Model..." });
+    const model = await Blip.getInstance(
+      weightsURL,
+      tokenizerURL,
+      configURL,
+      modelID,
+      quantized
+    );
+    self.postMessage({
+      status: "status",
+      message: "Running Blip Inference...",
+    });
+    const imageArrayU8 = await fetchArrayBuffer(imageURL, false);
+    const output = model.generate_caption_from_image(imageArrayU8);
+
+    self.postMessage({
+      status: "complete",
+      message: "complete",
+      output: output,
+    });
+  } catch (e) {
+    self.postMessage({ error: e });
+  }
+});