Use blurred canvas for thumbnails

src/components/appMediaViewerBase.ts

@@ -1292,7 +1292,7 @@ export default class AppMediaViewerBase<
     const size = appPhotosManager.setAttachmentSize(media, container, maxWidth, maxHeight, mediaSizes.isMobile ? false : true, undefined, !!(isDocument && media.w && media.h)).photoSize;
     if(useContainerAsTarget) {
       const cacheContext = appDownloadManager.getCacheContext(media, size.type);
-      let img: HTMLImageElement;
+      let img: HTMLImageElement | HTMLCanvasElement;
       if(cacheContext.downloaded) {
         img = new Image();
         img.src = cacheContext.url;

src/components/audio.ts

@@ -532,7 +532,7 @@ export default class AudioElement extends HTMLElement {
     };
 
     if(doc.thumbs?.length) {
-      const imgs: HTMLImageElement[] = [];
+      const imgs: HTMLElement[] = [];
       const wrapped = wrapPhoto({
         photo: doc, 
         message: null, 

src/components/sidebarLeft/tabs/background.ts

@@ -425,14 +425,14 @@ export default class AppBackgroundTab extends SliderSuperTab {
       const cacheContext = appDownloadManager.getCacheContext(doc);
       if(background.blur) {
         setTimeout(() => {
-          blur(cacheContext.url, 12, 4)
-          .then(url => {
+          const {canvas, promise} = blur(cacheContext.url, 12, 4)
+          promise.then(() => {
             if(!middleware()) {
               deferred.resolve();
               return;
             }
 
-            onReady(url);
+            onReady(canvas.toDataURL());
           });
         }, 200);
       } else {

src/components/wrappers.ts

@@ -625,7 +625,7 @@ export function wrapDocument({message, withTime, fontWeight, voiceAsMusic, showS
   if((doc.thumbs?.length || (message.pFlags.is_outgoing && cacheContext.url && doc.type === 'photo'))/*  && doc.mime_type !== 'image/gif' */) {
     docDiv.classList.add('document-with-thumb');
 
-    let imgs: HTMLImageElement[] = [];
+    let imgs: (HTMLImageElement | HTMLCanvasElement)[] = [];
     // ! WARNING, use thumbs for check when thumb will be generated for media
     if(message.pFlags.is_outgoing && ['photo', 'video'].includes(doc.type)) {
       icoDiv.innerHTML = `<img src="${cacheContext.url}">`;
@@ -887,7 +887,7 @@ export function wrapPhoto({photo, message, container, boxWidth, boxHeight, withT
 
   let isFit = true;
   let loadThumbPromise: Promise<any> = Promise.resolve();
-  let thumbImage: HTMLImageElement;
+  let thumbImage: HTMLImageElement | HTMLCanvasElement;
   let image: HTMLImageElement;
   let cacheContext: ThumbCache;
   const isGif = photo._ === 'document' && photo.mime_type === 'image/gif' && !size;
@@ -1000,8 +1000,10 @@ export function wrapPhoto({photo, message, container, boxWidth, boxHeight, withT
     if(middleware && !middleware()) return Promise.resolve();
 
     if(blurAfter) {
-      return blur(cacheContext.url, 12).then(url => {
-        return renderOnLoad(url);
+      const result = blur(cacheContext.url, 12);
+      return result.promise.then(() => {
+        // image = result.canvas;
+        return renderOnLoad(result.canvas.toDataURL());
       });
     }
 
@@ -1069,12 +1071,13 @@ export function wrapPhoto({photo, message, container, boxWidth, boxHeight, withT
   };
 }
 
-export function renderImageWithFadeIn(container: HTMLElement, 
+export function renderImageWithFadeIn(
+  container: HTMLElement, 
   image: HTMLImageElement, 
   url: string, 
   needFadeIn: boolean, 
   aspecter = container,
-  thumbImage?: HTMLImageElement
+  thumbImage?: HTMLElement
 ) {
   if(needFadeIn) {
     image.classList.add('fade-in');

src/environment/canvasFilterSupport.ts

@@ -0,0 +1,3 @@
+const IS_CANVAS_FILTER_SUPPORTED = 'filter' in (document.createElement('canvas').getContext('2d') || {});
+
+export default IS_CANVAS_FILTER_SUPPORTED;

src/helpers/blur.ts

@@ -6,14 +6,14 @@
 
 import type fastBlur from '../vendor/fastBlur';
 import addHeavyTask from './heavyQueue';
+import IS_CANVAS_FILTER_SUPPORTED from '../environment/canvasFilterSupport';
 
 const RADIUS = 2;
 const ITERATIONS = 2;
 
-const isFilterAvailable = 'filter' in (document.createElement('canvas').getContext('2d') || {});
 let requireBlurPromise: Promise<any>;
 let fastBlurFunc: typeof fastBlur;
-if(!isFilterAvailable) {
+if(!IS_CANVAS_FILTER_SUPPORTED) {
   requireBlurPromise = import('../vendor/fastBlur').then(m => {
     fastBlurFunc = m.default;
   });
@@ -21,80 +21,80 @@ if(!isFilterAvailable) {
   requireBlurPromise = Promise.resolve();
 }
 
-function processBlurNext(img: HTMLImageElement, radius: number, iterations: number) {
-  return new Promise<string>((resolve) => {
-    const canvas = document.createElement('canvas');
-    canvas.width = img.width;
-    canvas.height = img.height;
-    
-    const ctx = canvas.getContext('2d', {alpha: false});
-    if(isFilterAvailable) {
-      ctx.filter = `blur(${radius}px)`;
-      ctx.drawImage(img, -radius * 2, -radius * 2, canvas.width + radius * 4, canvas.height + radius * 4);
-    } else {
-      ctx.drawImage(img, 0, 0);
-      fastBlurFunc(ctx, 0, 0, canvas.width, canvas.height, radius, iterations);
-    }
-    
-    resolve(canvas.toDataURL());
-    /* if(DEBUG) {
-      console.log(`[blur] end, radius: ${radius}, iterations: ${iterations}, time: ${performance.now() - perf}`);
-    } */
+function processBlurNext(
+  img: HTMLImageElement, 
+  radius: number, 
+  iterations: number, 
+  canvas: HTMLCanvasElement = document.createElement('canvas')
+) {
+  canvas.width = img.width;
+  canvas.height = img.height;
 
-    /* canvas.toBlob(blob => {
-      resolve(URL.createObjectURL(blob));
-      
-      if(DEBUG) {
-        console.log(`[blur] end, radius: ${radius}, iterations: ${iterations}, time: ${performance.now() - perf}`);
-      }
-    }); */
-  });
+  const ctx = canvas.getContext('2d', {alpha: false});
+  if(IS_CANVAS_FILTER_SUPPORTED) {
+    ctx.filter = `blur(${radius}px)`;
+    ctx.drawImage(img, -radius * 2, -radius * 2, canvas.width + radius * 4, canvas.height + radius * 4);
+  } else {
+    ctx.drawImage(img, 0, 0);
+    fastBlurFunc(ctx, 0, 0, canvas.width, canvas.height, radius, iterations);
+  }
+
+  return canvas;
 }
 
-const blurPromises: Map<string, Promise<string>> = new Map();
-const CACHE_SIZE = 1000;
+type CacheValue = {canvas: HTMLCanvasElement, promise: Promise<void>};
+const cache: Map<string, CacheValue> = new Map();
+const CACHE_SIZE = 150;
 
 export default function blur(dataUri: string, radius: number = RADIUS, iterations: number = ITERATIONS) {
   if(!dataUri) {
-    console.error('no dataUri for blur', dataUri);
-    return Promise.resolve(dataUri);
+    throw 'no dataUri for blur: ' + dataUri;
   }
 
-  if(blurPromises.size > CACHE_SIZE) {
-    blurPromises.clear();
+  if(cache.size > CACHE_SIZE) {
+    cache.clear();
   }
-  
-  if(blurPromises.has(dataUri)) return blurPromises.get(dataUri);
-  const promise = new Promise<string>((resolve) => {
-    //return resolve(dataUri);
-    requireBlurPromise.then(() => {
-      const img = new Image();
-      img.onload = () => {
-        if(isFilterAvailable) {
-          processBlurNext(img, radius, iterations).then(resolve);
-        } else {
-          addHeavyTask({
-            items: [[img, radius, iterations]],
-            context: null,
-            process: processBlurNext
-          }, 'unshift').then(results => {
-            resolve(results[0]);
-          });
-        }
-      };
-      img.src = dataUri;
 
-      /* addHeavyTask({
-        items: [[dataUri, radius, iterations]],
-        context: null,
-        process: processBlur
-      }, 'unshift').then(results => {
-        resolve(results[0]);
-      }); */
+  const canvas = document.createElement('canvas');
+  canvas.className = 'canvas-thumbnail';
+  
+  let cached = cache.get(dataUri);
+  if(!cached) {
+    const promise: CacheValue['promise'] = new Promise((resolve) => {
+      //return resolve(dataUri);
+      requireBlurPromise.then(() => {
+        const img = new Image();
+        img.onload = () => {
+          // if(IS_CANVAS_FILTER_SUPPORTED) {
+            // resolve(processBlurNext(img, radius, iterations));
+          // } else {
+            const promise = addHeavyTask({
+              items: [[img, radius, iterations, canvas]],
+              context: null,
+              process: processBlurNext
+            }, 'unshift');
+            
+            promise.then(() => {
+              resolve();
+            });
+          // }
+        };
+        img.src = dataUri;
+      });
     });
-  });
-
-  blurPromises.set(dataUri, promise);
+  
+    cache.set(dataUri, cached = {
+      canvas,
+      promise
+    });
+  } else {
+    canvas.width = cached.canvas.width;
+    canvas.height = cached.canvas.height;
+    canvas.getContext('2d').drawImage(cached.canvas, 0, 0);
+  }
 
-  return promise;
+  return {
+    ...cached,
+    canvas
+  };
 }

src/helpers/bytes/bytesToDataURL.ts

@@ -0,0 +1,3 @@
+export default function bytesToDataURL(bytes: Uint8Array, mimeType: string = 'image/jpeg') {
+  return `data:${mimeType};base64,${btoa(String.fromCharCode(...bytes))}`;
+}

src/helpers/dom/renderImageFromUrl.ts

@@ -17,7 +17,7 @@ const set = (elem: HTMLElement | HTMLImageElement | SVGImageElement | HTMLVideoE
 export default function renderImageFromUrl(
   elem: HTMLElement | HTMLImageElement | SVGImageElement | HTMLVideoElement, 
   url: string, 
-  callback?: (err?: Event) => void, 
+  callback?: () => void, 
   useCache = true
 ) {
   if(!url) {
@@ -61,7 +61,7 @@ export default function renderImageFromUrl(
 }
 
 export function renderImageFromUrlPromise(elem: Parameters<typeof renderImageFromUrl>[0], url: string, useCache?: boolean) {
-  return new Promise<Event>((resolve) => {
+  return new Promise<void>((resolve) => {
     renderImageFromUrl(elem, url, resolve, useCache);
   });
 }

src/helpers/heavyQueue.ts

@@ -7,26 +7,27 @@
 import deferredPromise, { CancellablePromise } from "./cancellablePromise";
 import { getHeavyAnimationPromise } from "../hooks/useHeavyAnimationCheck";
 import { fastRaf } from "./schedulers";
+import { ArgumentTypes } from "../types";
 
-type HeavyQueue<T> = {
-  items: any[], 
-  process: (...args: any[]) => T,
+type HeavyQueue<T extends HeavyQueue<any>> = {
+  items: ArgumentTypes<T['process']>[], 
+  process: (...args: any[]) => ReturnType<T['process']>,
   context: any,
-  promise?: CancellablePromise<ReturnType<HeavyQueue<T>['process']>[]>
+  promise?: CancellablePromise<ReturnType<T['process']>[]>
 };
 const heavyQueue: HeavyQueue<any>[] = [];
 let processingQueue = false;
 
-export default function addHeavyTask<T>(queue: HeavyQueue<T>, method: 'push' | 'unshift' = 'push') {
+export default function addHeavyTask<T extends HeavyQueue<T>>(queue: T, method: 'push' | 'unshift' = 'push') {
   if(!queue.items.length) {
-    return Promise.resolve([]);
+    return Promise.resolve([]) as typeof promise;
   }
   
-  queue.promise = deferredPromise<T[]>();
+  const promise = queue.promise = deferredPromise();
   heavyQueue[method](queue);
   processHeavyQueue();
 
-  return queue.promise;
+  return promise;
 }
 
 function processHeavyQueue() {
@@ -41,23 +42,24 @@ function processHeavyQueue() {
   }
 }
 
-function timedChunk<T>(queue: HeavyQueue<T>) {
+function timedChunk<T extends HeavyQueue<T>>(queue: HeavyQueue<T>) {
   if(!queue.items.length) {
-    queue.promise.resolve([]);
+    queue.promise.resolve([] as any);
     return Promise.resolve([]);
   }
 
   const todo = queue.items.slice();
-  const results: T[] = [];
+  const results: ReturnType<T['process']>[] = [];
 
-  return new Promise<T[]>((resolve, reject) => {
+  return new Promise<typeof results>((resolve, reject) => {
     const f = async() => {
       const start = performance.now();
 
       do {
         await getHeavyAnimationPromise();
         const possiblePromise = queue.process.apply(queue.context, todo.shift());
-        let realResult: T;
+        let realResult: typeof results[0];
+        // @ts-ignore
         if(possiblePromise instanceof Promise) {
           try {
             realResult = await possiblePromise;

src/lib/appManagers/appDocsManager.ts

@@ -314,8 +314,9 @@ export class AppDocsManager {
     const cacheContext = appDownloadManager.getCacheContext(doc, thumb.type);
     if(!cacheContext.url) {
       if('bytes' in thumb) {
-        promise = blur(appPhotosManager.getPreviewURLFromBytes(thumb.bytes, !!doc.sticker)).then(url => {
-          cacheContext.url = url;
+        const result = blur(appPhotosManager.getPreviewURLFromBytes(thumb.bytes, !!doc.sticker));
+        promise = result.promise.then(() => {
+          cacheContext.url = result.canvas.toDataURL();
         }) as any;
       } else {
         //return this.getFileURL(doc, false, thumb);

src/lib/appManagers/appPhotosManager.ts

@@ -28,6 +28,7 @@ import windowSize from "../../helpers/windowSize";
 import bytesFromHex from "../../helpers/bytes/bytesFromHex";
 import isObject from "../../helpers/object/isObject";
 import safeReplaceArrayInObject from "../../helpers/object/safeReplaceArrayInObject";
+import bytesToDataURL from "../../helpers/bytes/bytesToDataURL";
 
 export type MyPhoto = Photo.photo;
 
@@ -171,8 +172,7 @@ export class AppPhotosManager {
       mimeType = 'image/jpeg';
     }
 
-    const blob = new Blob([arr], {type: mimeType});
-    return URL.createObjectURL(blob);
+    return bytesToDataURL(arr, mimeType);
   }
 
   /**
@@ -210,14 +210,19 @@ export class AppPhotosManager {
   public getImageFromStrippedThumb(photo: MyPhoto | MyDocument, thumb: PhotoSize.photoCachedSize | PhotoSize.photoStrippedSize, useBlur: boolean) {
     const url = this.getPreviewURLFromThumb(photo, thumb, false);
 
-    const image = new Image();
-    image.classList.add('thumbnail');
+    let element: HTMLImageElement | HTMLCanvasElement, loadPromise: Promise<void>;
+    if(!useBlur) {
+      element = new Image();
+      loadPromise = renderImageFromUrlPromise(element, url);
+    } else {
+      const result = blur(url);
+      element = result.canvas;
+      loadPromise = result.promise;
+    }
 
-    const loadPromise = (useBlur ? blur(url) : Promise.resolve(url)).then(url => {
-      return renderImageFromUrlPromise(image, url);
-    });
+    element.classList.add('thumbnail');
     
-    return {image, loadPromise};
+    return {image: element, loadPromise};
   }
   
   public setAttachmentSize(

src/scss/style.scss

@@ -1213,6 +1213,12 @@ middle-ellipsis-element {
   fill: rgba(0, 0, 0, .08);
 }
 
+.canvas-thumbnail {
+  position: absolute;
+  width: 100%;
+  height: 100%;
+}
+
 .media-photo, 
 .media-video, 
 .media-sticker,