Option to send photos as high quality

ts/util/scaleImageToLevel.ts

@@ -0,0 +1,145 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import loadImage from 'blueimp-load-image';
+
+import { IMAGE_JPEG } from '../types/MIME';
+import { canvasToBlob } from './canvasToBlob';
+import { getValue } from '../RemoteConfig';
+
+enum MediaQualityLevels {
+  One = 1,
+  Two = 2,
+  Three = 3,
+}
+
+const DEFAULT_LEVEL = MediaQualityLevels.One;
+
+const MiB = 1024 * 1024;
+
+const DEFAULT_LEVEL_DATA = {
+  maxDimensions: 1600,
+  quality: 0.7,
+  size: MiB,
+};
+
+const MEDIA_QUALITY_LEVEL_DATA = new Map([
+  [MediaQualityLevels.One, DEFAULT_LEVEL_DATA],
+  [
+    MediaQualityLevels.Two,
+    {
+      maxDimensions: 2048,
+      quality: 0.75,
+      size: MiB * 1.5,
+    },
+  ],
+  [
+    MediaQualityLevels.Three,
+    {
+      maxDimensions: 4096,
+      quality: 0.75,
+      size: MiB * 3,
+    },
+  ],
+]);
+
+const SCALABLE_DIMENSIONS = [3072, 2048, 1600, 1024, 768];
+const MIN_DIMENSIONS = 512;
+
+function parseCountryValues(values: string): Map<string, MediaQualityLevels> {
+  const map = new Map<string, MediaQualityLevels>();
+  values.split(',').forEach(value => {
+    const [countryCode, level] = value.split(':');
+    map.set(
+      countryCode,
+      Number(level) === 2 ? MediaQualityLevels.Two : MediaQualityLevels.One
+    );
+  });
+  return map;
+}
+
+function getMediaQualityLevel(): MediaQualityLevels {
+  const values = getValue('desktop.mediaQuality.levels');
+  if (!values) {
+    return DEFAULT_LEVEL;
+  }
+  const countryValues = parseCountryValues(values);
+  const e164 = window.textsecure.storage.user.getNumber();
+  if (!e164) {
+    return DEFAULT_LEVEL;
+  }
+  const parsedPhoneNumber = window.libphonenumber.util.parseNumber(e164);
+
+  if (!parsedPhoneNumber.isValidNumber) {
+    return DEFAULT_LEVEL;
+  }
+
+  const level = countryValues.get(parsedPhoneNumber.countryCode);
+  if (level) {
+    return level;
+  }
+
+  return countryValues.get('*') || DEFAULT_LEVEL;
+}
+
+async function getCanvasBlob(
+  image: HTMLCanvasElement,
+  dimensions: number,
+  quality: number
+): Promise<Blob> {
+  const canvas = loadImage.scale(image, {
+    canvas: true,
+    maxHeight: dimensions,
+    maxWidth: dimensions,
+  });
+  if (!(canvas instanceof HTMLCanvasElement)) {
+    throw new Error('image not a canvas');
+  }
+  return canvasToBlob(canvas, IMAGE_JPEG, quality);
+}
+
+export async function scaleImageToLevel(
+  fileOrBlobOrURL: File | Blob,
+  sendAsHighQuality?: boolean
+): Promise<Blob> {
+  let image: HTMLCanvasElement;
+  try {
+    const data = await loadImage(fileOrBlobOrURL, {
+      canvas: true,
+      orientation: true,
+    });
+    if (!(data.image instanceof HTMLCanvasElement)) {
+      throw new Error('image not a canvas');
+    }
+    ({ image } = data);
+    if (!(image instanceof HTMLCanvasElement)) {
+      throw new Error('image not a canvas');
+    }
+  } catch (err) {
+    const error = new Error('scaleImageToLevel: Failed to process image');
+    error.originalError = err;
+    throw error;
+  }
+
+  const level = sendAsHighQuality
+    ? MediaQualityLevels.Three
+    : getMediaQualityLevel();
+  const { maxDimensions, quality, size } =
+    MEDIA_QUALITY_LEVEL_DATA.get(level) || DEFAULT_LEVEL_DATA;
+
+  for (let i = 0; i < SCALABLE_DIMENSIONS.length; i += 1) {
+    const scalableDimensions = SCALABLE_DIMENSIONS[i];
+    if (maxDimensions < scalableDimensions) {
+      continue;
+    }
+
+    // We need these operations to be in serial
+    // eslint-disable-next-line no-await-in-loop
+    const blob = await getCanvasBlob(image, scalableDimensions, quality);
+    if (blob.size <= size) {
+      return blob;
+    }
+  }
+
+  return getCanvasBlob(image, MIN_DIMENSIONS, quality);
+}