diff --git a/locales/index.d.ts b/locales/index.d.ts
index beccac4a1d..a3cb8e1799 100644
--- a/locales/index.d.ts
+++ b/locales/index.d.ts
@@ -10661,6 +10661,24 @@ export interface Locale extends ILocale {
          */
         "sent": string;
     };
+    "_watermarkEditor": {
+        /**
+         * このファイルは対応していません
+         */
+        "driveFileTypeWarn": string;
+        /**
+         * 画像ファイルを選択してください
+         */
+        "driveFileTypeWarnDescription": string;
+        /**
+         * 描画モード
+         */
+        "repeatSetting": string;
+        /**
+         * 全体を埋め尽くす
+         */
+        "repeat": string;
+    };
 }
 declare const locales: {
     [lang: string]: Locale;
diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 01fdd36abe..7f098e0e0d 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -2841,3 +2841,9 @@ _selfXssPrevention:
 _followRequest:
   recieved: "受け取った申請"
   sent: "送った申請"
+
+_watermarkEditor:
+  driveFileTypeWarn: "このファイルは対応していません"
+  driveFileTypeWarnDescription: "画像ファイルを選択してください"
+  repeatSetting: "描画モード"
+  repeat: "全体を埋め尽くす"
diff --git a/packages/frontend/src/components/MkWatermarkEditorDialog.anchor.vue b/packages/frontend/src/components/MkWatermarkEditorDialog.anchor.vue
new file mode 100644
index 0000000000..2728b0576c
--- /dev/null
+++ b/packages/frontend/src/components/MkWatermarkEditorDialog.anchor.vue
@@ -0,0 +1,94 @@
+<!--
+SPDX-FileCopyrightText: syuilo and misskey-project
+SPDX-License-Identifier: AGPL-3.0-only
+-->
+<template>
+<div :class="$style.anchorGridRoot">
+	<div v-for="anchor in watermarkAnchor" :class="$style.anchorGridItem">
+		<input type="radio" :name="id" :id="`${id}-${anchor}`" :value="anchor" :class="$style.anchorGridItemRadio" v-model="value"/>
+		<label :for="`${id}-${anchor}`" :class="$style.anchorGridItemLabel">
+			<div :class="$style.anchorGridItemInner">{{ langMap[anchor] }}</div>
+		</label>
+	</div>
+</div>
+</template>
+
+<script setup lang="ts">
+import { useId } from 'vue';
+import { i18n } from '@/i18n.js';
+import { watermarkAnchor } from '@/scripts/watermark.js';
+import type { WatermarkAnchor } from '@/scripts/watermark.js';
+
+const langMap = {
+	'top': i18n.ts.top,
+	'top-left': i18n.ts.leftTop,
+	'top-right': i18n.ts.rightTop,
+	'left': i18n.ts.left,
+	'right': i18n.ts.right,
+	'bottom': i18n.ts.bottom,
+	'bottom-left': i18n.ts.leftBottom,
+	'bottom-right': i18n.ts.rightBottom,
+	'center': i18n.ts.center,
+} satisfies Record<WatermarkAnchor, string>;
+
+const value = defineModel<WatermarkAnchor | undefined | null>({ required: true });
+
+const id = useId();
+</script>
+
+<style module>
+.anchorGridRoot {
+	position: relative;
+	display: grid;
+	grid-template-columns: repeat(3, 1fr);
+	grid-template-rows: repeat(3, 1fr);
+	border-radius: var(--MI-radius);
+	overflow: clip;
+	box-sizing: border-box;
+	border: thin solid var(--MI_THEME-divider);
+	background-color: var(--MI_THEME-divider);
+	gap: 1px;
+	max-width: 242px; /* 240px + 左右ボーダー2px */
+	width: 100%;
+	aspect-ratio: 3/2;
+	height: auto;
+}
+
+.anchorGridItemRadio {
+	position: absolute;
+	clip: rect(0, 0, 0, 0);
+	pointer-events: none;
+}
+
+.anchorGridItem {
+	background-color: var(--MI_THEME-panel);
+}
+
+.anchorGridItemLabel {
+	cursor: pointer;
+}
+
+.anchorGridItemInner {
+	width: 100%;
+	height: 100%;
+	box-sizing: border-box;
+	display: flex;
+	align-items: center;
+	justify-content: center;
+	padding: 4px;
+	font-size: 0.8em;
+}
+
+.anchorGridItemInner:hover {
+	background-color: var(--MI_THEME-buttonHoverBg);
+}
+
+.anchorGridItemRadio:checked + .anchorGridItemLabel .anchorGridItemInner {
+	background-color: var(--MI_THEME-accentedBg);
+	color: var(--MI_THEME-accent);
+}
+
+.anchorGridItemRadio:focus-visible + .anchorGridItemLabel .anchorGridItemInner {
+	outline: 2px solid var(--MI_THEME-accent);
+}
+</style>
diff --git a/packages/frontend/src/components/MkWatermarkEditorDialog.vue b/packages/frontend/src/components/MkWatermarkEditorDialog.vue
index f114824835..6fcbb46946 100644
--- a/packages/frontend/src/components/MkWatermarkEditorDialog.vue
+++ b/packages/frontend/src/components/MkWatermarkEditorDialog.vue
@@ -19,8 +19,8 @@ SPDX-License-Identifier: AGPL-3.0-only
 	<div :class="$style.watermarkEditorRoot">
 		<div :class="$style.watermarkEditorInputRoot">
 			<div :class="$style.watermarkEditorPreviewRoot">
-				<MkLoading v-if="canvasLoading" :class="$style.watermarkEditorPreviewSpinner"/>
 				<canvas ref="canvasEl" :class="$style.watermarkEditorPreviewCanvas"></canvas>
+				<MkLoading v-if="canvasLoading" :class="$style.watermarkEditorPreviewSpinner"/>
 				<div :class="$style.watermarkEditorPreviewWrapper">
 					<div class="_acrylic" :class="$style.watermarkEditorPreviewTitle">{{ i18n.ts.preview }}</div>
 				</div>
@@ -30,6 +30,39 @@ SPDX-License-Identifier: AGPL-3.0-only
 					<template #label>{{ i18n.ts.useWatermark }}</template>
 					<template #caption>{{ i18n.ts.useWatermarkDescription }}</template>
 				</MkSwitch>
+
+				<div>
+					<div :class="$style.formLabel">{{ i18n.ts.watermark }}</div>
+					<div :class="$style.fileSelectorRoot">
+						<MkButton :class="$style.fileSelectorButton" inline rounded primary @click="chooseFile">{{ i18n.ts.selectFile }}</MkButton>
+						<div :class="['_nowrap', !fileUrl && $style.fileNotSelected]">{{ friendlyFileName }}</div>
+					</div>
+				</div>
+
+				<template v-if="fileId != null || fileUrl != null">
+					<MkRange v-model="sizeRatio" :min="0" :max="1" :step="0.01" :textConverter="(v) => `${Math.floor(v * 100)}%`">
+						<template #label>{{ i18n.ts.size }}</template>
+					</MkRange>
+
+					<MkRange v-model="opacity" :min="0" :max="1" :step="0.01" :textConverter="(v) => `${Math.floor(v * 100)}%`">
+						<template #label>{{ i18n.ts.opacity }}</template>
+					</MkRange>
+
+					<MkRange v-model="rotate" :min="-45" :max="45" :textConverter="(v) => `${Math.floor(v)}°`">
+						<template #label>{{ i18n.ts.rotate }}</template>
+					</MkRange>
+
+					<MkRadios v-model="repeat">
+						<template #label>{{ i18n.ts._watermarkEditor.repeatSetting }}</template>
+						<option :value="true">{{ i18n.ts._watermarkEditor.repeat }}</option>
+						<option :value="false">{{ i18n.ts.normal }}</option>
+					</MkRadios>
+
+					<div v-if="watermarkConfig?.repeat !== true">
+						<div :class="$style.formLabel">{{ i18n.ts.position }}</div>
+						<XAnchorSelector v-model="anchor"/>
+					</div>
+				</template>
 			</div>
 		</div>
 	</div>
@@ -37,13 +70,21 @@ SPDX-License-Identifier: AGPL-3.0-only
 </template>
 
 <script setup lang="ts">
-import { shallowRef, ref, useTemplateRef, computed, onMounted } from 'vue';
+import { shallowRef, ref, useTemplateRef, computed, watch, onMounted } from 'vue';
 import MkModalWindow from '@/components/MkModalWindow.vue';
+import MkButton from '@/components/MkButton.vue';
+import MkRadios from '@/components/MkRadios.vue';
 import MkSwitch from '@/components/MkSwitch.vue';
+import MkInput from '@/components/MkInput.vue';
+import MkRange from '@/components/MkRange.vue';
+import XAnchorSelector from '@/components/MkWatermarkEditorDialog.anchor.vue';
 
+import * as os from '@/os.js';
 import { defaultStore } from '@/store.js';
 import { i18n } from '@/i18n.js';
-import { applyWatermark, WatermarkConfig } from '@/scripts/watermark.js';
+import { selectFile } from '@/scripts/select-file.js';
+import { applyWatermark, canPreview, WatermarkConfig } from '@/scripts/watermark.js';
+import { misskeyApi } from '@/scripts/misskey-api.js';
 
 const emit = defineEmits<{
 	(ev: 'ok'): void;
@@ -67,26 +108,109 @@ function save() {
 
 //#region 設定
 const useWatermark = computed(defaultStore.makeGetterSetter('useWatermark'));
-const watermarkConfig = ref<WatermarkConfig>(defaultStore.state.watermarkConfig ?? {
-	fileUrl: '/client-assets/default-watermark.png',
-	enlargement: 'contain',
-	opacity: 0.5,
-	anchor: 'bottom-right',
-	gravity: 'auto',
+const watermarkConfig = ref<Partial<WatermarkConfig> | null>(defaultStore.state.watermarkConfig ?? {
+	opacity: 0.2,
 	repeat: true,
 	rotate: 15,
-	__bypassMediaProxy: true,
+	sizeRatio: 0.2,
 });
+const anchor = computed({
+	get: () => watermarkConfig.value != null && 'anchor' in watermarkConfig.value ? watermarkConfig.value.anchor : null,
+	set: (v) => {
+		if (v == null || watermarkConfig.value?.repeat === true) {
+			watermarkConfig.value = { ...watermarkConfig.value, anchor: undefined };
+		} else if (watermarkConfig.value?.repeat === false) {
+			watermarkConfig.value = { ...watermarkConfig.value, anchor: v };
+		}
+	},
+});
+const sizeRatio = computed({
+	get: () => watermarkConfig.value?.sizeRatio ?? 0.2,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, sizeRatio: v },
+});
+const repeat = computed({
+	get: () => watermarkConfig.value?.repeat ?? true,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, repeat: v },
+});
+const opacity = computed({
+	get: () => watermarkConfig.value?.opacity ?? 0.2,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, opacity: v },
+});
+const rotate = computed({
+	get: () => watermarkConfig.value?.rotate ?? 15,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, rotate: v },
+});
+//#endregion
+
+//#region ファイル選択
+const fileId = computed({
+	get: () => watermarkConfig.value?.fileId,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, fileId: v },
+});
+const fileUrl = computed({
+	get: () => watermarkConfig.value?.fileUrl,
+	set: (v) => watermarkConfig.value = { ...watermarkConfig.value, fileUrl: v },
+});
+const fileName = ref<string>('');
+const driveFileError = ref(false);
+onMounted(async () => {
+	if (watermarkConfig.value?.fileId != null) {
+		await misskeyApi('drive/files/show', {
+			fileId: watermarkConfig.value.fileId,
+		}).then((res) => {
+			fileName.value = res.name;
+		}).catch((err) => {
+			driveFileError.value = true;
+		});
+	}
+});
+const friendlyFileName = computed<string>(() => {
+	if (fileName.value) {
+		return fileName.value;
+	}
+	if (fileUrl.value) {
+		return fileUrl.value;
+	}
+
+	return i18n.ts._soundSettings.driveFileWarn;
+});
+
+function chooseFile(ev: MouseEvent) {
+	selectFile(ev.currentTarget ?? ev.target, {
+		label: i18n.ts.selectFile,
+		dontUseWatermark: true,
+	}).then((file) => {
+		if (!file.type.startsWith('image')) {
+			os.alert({
+				type: 'warning',
+				title: i18n.ts._watermarkEditor.driveFileTypeWarn,
+				text: i18n.ts._watermarkEditor.driveFileTypeWarnDescription,
+			});
+			return;
+		}
+
+		fileId.value = file.id;
+		fileUrl.value = file.url;
+		fileName.value = file.name;
+		driveFileError.value = false;
+	});
+}
 //#endregion
 
 //#region Canvasの制御
 const canvasLoading = ref(true);
 const canvasEl = useTemplateRef('canvasEl');
 onMounted(() => {
-	if (canvasEl.value) {
-		applyWatermark('/client-assets/hill.webp', canvasEl.value, watermarkConfig.value);
-	}
+	watch([useWatermark, watermarkConfig], ([useWatermarkTo, watermarkConfigTo]) => {
+		canvasLoading.value = true;
+		if (canvasEl.value) {
+			applyWatermark('/client-assets/hill.webp', canvasEl.value, useWatermarkTo && canPreview(watermarkConfigTo) ? watermarkConfigTo : null).then(() => {
+				canvasLoading.value = false;
+			});
+		}
+	}, { immediate: true, deep: true });
 });
+
 //#endregion
 </script>
 
@@ -168,45 +292,31 @@ onMounted(() => {
 	overflow-y: scroll;
 }
 
-.watermarkEditorResultRoot {
-	box-sizing: border-box;
-	padding: 24px;
-	height: 100%;
-	max-width: 700px;
-	margin: 0 auto;
+.formLabel {
+	font-size: 0.85em;
+	padding: 0 0 8px 0;
+}
+
+.fileSelectorRoot {
 	display: flex;
 	align-items: center;
+	gap: 8px;
 }
 
-.watermarkEditorResultHeading {
-	text-align: center;
-	font-size: 1.2em;
+.fileErrorRoot {
+	flex-grow: 1;
+	min-width: 0;
+	font-weight: 700;
+	color: var(--MI_THEME-error);
 }
 
-.watermarkEditorResultHeadingIcon {
-	margin: 0 auto;
-	background-color: var(--MI_THEME-accentedBg);
-	color: var(--MI_THEME-accent);
-	text-align: center;
-	height: 64px;
-	width: 64px;
-	font-size: 24px;
-	line-height: 64px;
-	border-radius: 50%;
+.fileSelectorButton {
+	flex-shrink: 0;
 }
 
-.watermarkEditorResultDescription {
-	text-align: center;
-	white-space: pre-wrap;
-}
-
-.watermarkEditorResultWrapper,
-.watermarkEditorResultCode {
-	width: 100%;
-}
-
-.watermarkEditorResultButtons {
-	margin: 0 auto;
+.fileNotSelected {
+	font-weight: 700;
+	color: var(--MI_THEME-infoWarnFg);
 }
 
 @container (max-width: 800px) {
diff --git a/packages/frontend/src/scripts/upload.ts b/packages/frontend/src/scripts/upload.ts
index e9991ba69c..bc19fefc2d 100644
--- a/packages/frontend/src/scripts/upload.ts
+++ b/packages/frontend/src/scripts/upload.ts
@@ -14,6 +14,7 @@ import { $i } from '@/account.js';
 import { alert } from '@/os.js';
 import { i18n } from '@/i18n.js';
 import { instance } from '@/instance.js';
+import { canPreview, getWatermarkAppliedImage } from './watermark.js';
 
 type Uploading = {
 	id: string;
@@ -68,22 +69,27 @@ export function uploadFile(
 
 			uploads.value.push(ctx);
 
-			const config = !keepOriginal ? await getCompressionConfig(file) : undefined;
-			let resizedImage: Blob | undefined;
+			let _file: Blob = file;
+			
+			if (_file.type.startsWith('image/') && watermark && canPreview(defaultStore.state.watermarkConfig)) {
+				_file = await getWatermarkAppliedImage(_file, defaultStore.state.watermarkConfig);
+			}
+
+			const config = !keepOriginal ? await getCompressionConfig(_file) : undefined;
 			if (config) {
 				try {
-					const resized = await readAndCompressImage(file, config);
-					if (resized.size < file.size || file.type === 'image/webp') {
+					const resized = await readAndCompressImage(_file, config);
+					if (resized.size < _file.size || _file.type === 'image/webp') {
 						// The compression may not always reduce the file size
 						// (and WebP is not browser safe yet)
-						resizedImage = resized;
+						_file = resized;
 					}
 					if (_DEV_) {
-						const saved = ((1 - resized.size / file.size) * 100).toFixed(2);
-						console.log(`Image compression: before ${file.size} bytes, after ${resized.size} bytes, saved ${saved}%`);
+						const saved = ((1 - resized.size / _file.size) * 100).toFixed(2);
+						console.log(`Image compression: before ${_file.size} bytes, after ${resized.size} bytes, saved ${saved}%`);
 					}
 
-					ctx.name = file.type !== config.mimeType ? `${ctx.name}.${mimeTypeMap[config.mimeType]}` : ctx.name;
+					ctx.name = _file.type !== config.mimeType ? `${ctx.name}.${mimeTypeMap[config.mimeType]}` : ctx.name;
 				} catch (err) {
 					console.error('Failed to resize image', err);
 				}
@@ -92,7 +98,7 @@ export function uploadFile(
 			const formData = new FormData();
 			formData.append('i', $i!.token);
 			formData.append('force', 'true');
-			formData.append('file', resizedImage ?? file);
+			formData.append('file', _file);
 			formData.append('name', ctx.name);
 			if (_folder) formData.append('folderId', _folder);
 
diff --git a/packages/frontend/src/scripts/upload/compress-config.ts b/packages/frontend/src/scripts/upload/compress-config.ts
index 3046b7f518..bd39527147 100644
--- a/packages/frontend/src/scripts/upload/compress-config.ts
+++ b/packages/frontend/src/scripts/upload/compress-config.ts
@@ -21,7 +21,7 @@ const compressTypeMapFallback = {
 	'image/svg+xml': { quality: 1, mimeType: 'image/png' },
 } as const;
 
-export async function getCompressionConfig(file: File): Promise<BrowserImageResizerConfigWithConvertedOutput | undefined> {
+export async function getCompressionConfig(file: Blob): Promise<BrowserImageResizerConfigWithConvertedOutput | undefined> {
 	const imgConfig = (isWebpSupported() ? compressTypeMap : compressTypeMapFallback)[file.type];
 	if (!imgConfig || await isAnimated(file)) {
 		return;
diff --git a/packages/frontend/src/scripts/watermark.ts b/packages/frontend/src/scripts/watermark.ts
index 36add1b61f..b810a36dc1 100644
--- a/packages/frontend/src/scripts/watermark.ts
+++ b/packages/frontend/src/scripts/watermark.ts
@@ -5,26 +5,57 @@
 import { getProxiedImageUrl } from "@/scripts/media-proxy.js";
 import { misskeyApi } from "@/scripts/misskey-api.js";
 
+export const watermarkAnchor = [
+	'top-left',
+	'top',
+	'top-right',
+	'left',
+	'center',
+	'right',
+	'bottom-left',
+	'bottom',
+	'bottom-right',
+] as const;
+
+export type WatermarkAnchor = typeof watermarkAnchor[number];
+
 export type WatermarkConfig = {
+	/** ドライブファイルのID */
 	fileId?: string;
+	/** 画像URL */
 	fileUrl?: string;
-	width?: number;
-	height?: number;
-	enlargement: 'scale-down' | 'contain' | 'cover' | 'crop' | 'pad';
-	gravity: 'auto' | 'left' | 'right' | 'top' | 'bottom';
+	/** 親画像に対するウォーターマークの幅比率。ない場合は1。親画像が縦長の場合は幅の比率として、横長の場合は高さ比率として使用される */
+	sizeRatio?: number;
+	/** 透明度 */
 	opacity?: number;
-	repeat: true | false | 'x' | 'y';
-	anchor: 'center' | 'top' | 'left' | 'bottom' | 'right' | 'top-left' | 'top-right' | 'bottom-left' | 'bottom-right';
-	offsetTop?: number;
-	offsetLeft?: number;
-	offsetBottom?: number;
-	offsetRight?: number;
-	backgroundColor?: string;
+	/** 回転角度（度数） */
 	rotate?: number;
+	/** パディング */
+	padding?: {
+		top: number;
+		right: number;
+		bottom: number;
+		left: number;
+	};
 
 	/** @internal */
 	__bypassMediaProxy?: boolean;
-};
+} & ({
+	/** 繰り返し */
+	repeat?: false;
+	/** 画像の始祖点 */
+	anchor: WatermarkAnchor;
+} | {
+	/** 繰り返し */
+	repeat: true;
+});
+
+/**
+ * プレビューに必要な値が全部揃っているかどうかを判定する
+ */
+export function canPreview(config: Partial<WatermarkConfig> | null): config is WatermarkConfig {
+	return config != null && (config.fileUrl != null || config.fileId != null);
+}
 
 /**
  * ウォーターマークを適用してキャンバスに描画する
@@ -33,7 +64,7 @@ export type WatermarkConfig = {
  * @param el ウォーターマークを適用するキャンバス
  * @param config ウォーターマークの設定
  */
-export async function applyWatermark(img: string | Blob, el: HTMLCanvasElement, config: WatermarkConfig) {
+export async function applyWatermark(img: string | Blob, el: HTMLCanvasElement, config: WatermarkConfig | null) {
 	const canvas = el;
 	const ctx = canvas.getContext('2d')!;
 	const imgEl = new Image();
@@ -41,91 +72,134 @@ export async function applyWatermark(img: string | Blob, el: HTMLCanvasElement,
 		canvas.width = imgEl.width;
 		canvas.height = imgEl.height;
 		ctx.drawImage(imgEl, 0, 0);
-		if (config.fileUrl) {
-			const watermark = new Image();
-			watermark.onload = () => {
-				const width = config.width || watermark.width;
-				const height = config.height || watermark.height;
-				ctx.globalAlpha = config.opacity ?? 1;
-				if (config.repeat !== false) {
-					const resizedWatermark = document.createElement('canvas');
-					resizedWatermark.width = width;
-					resizedWatermark.height = height;
-					const resizedCtx = resizedWatermark.getContext('2d')!;
-					resizedCtx.drawImage(watermark, 0, 0, width, height);
-					const pattern = ctx.createPattern(resizedWatermark, config.repeat === true ? 'repeat' : `repeat-${config.repeat}`);
-					if (pattern) {
-						ctx.fillStyle = pattern;
+
+		if (config != null) {
+			if (config.fileUrl) {
+				const watermark = new Image();
+				watermark.onload = () => {
+					const canvasAspectRatio = canvas.width / canvas.height; // 横長は1より大きい
+					const watermarkAspectRatio = watermark.width / watermark.height; // 横長は1より大きい
+					const { width, height } = (() => {
+						const desiredWidth = canvas.width * (config.sizeRatio ?? 1);
+						const desiredHeight = canvas.height * (config.sizeRatio ?? 1);
+
+						if (
+							(watermarkAspectRatio > 1 && canvasAspectRatio > 1) ||
+							(watermarkAspectRatio < 1 && canvasAspectRatio < 1)
+						) {
+							return {
+								width: desiredWidth,
+								height: desiredWidth / watermarkAspectRatio
+							};
+						} else {
+							return {
+								width: desiredHeight * watermarkAspectRatio,
+								height: desiredHeight
+							};
+						}
+					})();
+
+					ctx.globalAlpha = config.opacity ?? 1;
+
+					if (config.repeat) {
+						// 余白をもたせた状態のウォーターマークを作成しておく
+						const resizedWatermark = document.createElement('canvas');
+						resizedWatermark.width = width + (config.padding ? (config.padding.left ?? 0) + (config.padding.right ?? 0) : 0);
+						resizedWatermark.height = height + (config.padding ? (config.padding.top ?? 0) + (config.padding.bottom ?? 0) : 0);
+						const resizedCtx = resizedWatermark.getContext('2d')!;
+						resizedCtx.drawImage(
+							watermark,
+							(config.padding ? config.padding.left ?? 0 : 0),
+							(config.padding ? config.padding.top ?? 0 : 0),
+							width,
+							height
+						);
+
+						const pattern = ctx.createPattern(resizedWatermark, config.repeat === true ? 'repeat' : `repeat-${config.repeat}`);
+						if (pattern) {
+							ctx.fillStyle = pattern;
+							if (config.rotate != null && config.rotate !== 0) {
+								const rotateRad = config.rotate * Math.PI / 180;
+								ctx.translate(canvas.width / 2, canvas.height / 2);
+								ctx.rotate(rotateRad);
+								ctx.translate(-canvas.width / 2, -canvas.height / 2);
+								const rotatedWidth = Math.abs(canvas.width * Math.cos(rotateRad)) + Math.abs(canvas.height * Math.sin(rotateRad));
+								const rotatedHeight = Math.abs(canvas.width * Math.sin(rotateRad)) + Math.abs(canvas.height * Math.cos(rotateRad));
+								const x = Math.abs(rotatedWidth - canvas.width) / -2;
+								const y = Math.abs(rotatedHeight - canvas.height) / -2;
+								ctx.fillRect(x, y, rotatedWidth, rotatedHeight);
+							} else {
+								ctx.fillRect(0, 0, canvas.width, canvas.height);
+							}
+						}
+					} else {
+						const x = (() => {
+							switch (config.anchor) {
+								case 'center':
+								case 'top':
+								case 'bottom':
+									return (canvas.width - width) / 2;
+								case 'left':
+								case 'top-left':
+								case 'bottom-left':
+									return 0 + (config.padding ? config.padding.left ?? 0 : 0);
+								case 'right':
+								case 'top-right':
+								case 'bottom-right':
+									return canvas.width - width - (config.padding ? config.padding.right ?? 0 : 0);
+							}
+						})();
+						const y = (() => {
+							let rotateY = 0; // 回転によるY座標の補正
+
+							if (config.rotate) {
+								const rotateRad = config.rotate * Math.PI / 180;
+								rotateY = Math.abs(Math.abs(width * Math.sin(rotateRad)) + Math.abs(height * Math.cos(rotateRad)) - height) / 2;
+							}
+
+							switch (config.anchor) {
+								case 'center':
+								case 'left':
+								case 'right':
+									return (canvas.height - height) / 2 + (config.padding ? config.padding.top ?? 0 : 0);
+								case 'top':
+								case 'top-left':
+								case 'top-right':
+									return rotateY;
+								case 'bottom':
+								case 'bottom-left':
+								case 'bottom-right':
+									return canvas.height - height - (config.padding ? config.padding.bottom ?? 0 : 0) - rotateY;
+							}
+						})();
+
 						if (config.rotate) {
 							const rotateRad = config.rotate * Math.PI / 180;
-							ctx.translate(canvas.width / 2, canvas.height / 2);
+							ctx.translate(x + width / 2, y + height / 2);
 							ctx.rotate(rotateRad);
-							ctx.translate(-canvas.width / 2, -canvas.height / 2);
-							const rotatedWidth = Math.abs(canvas.width * Math.cos(rotateRad)) + Math.abs(canvas.height * Math.sin(rotateRad));
-							const rotatedHeight = Math.abs(canvas.width * Math.sin(rotateRad)) + Math.abs(canvas.height * Math.cos(rotateRad));
-							const x = Math.abs(rotatedWidth - canvas.width) / -2;
-							const y = Math.abs(rotatedHeight - canvas.height) / -2;
-							ctx.fillRect(x, y, rotatedWidth, rotatedHeight);
-						} else {
-							ctx.fillRect(0, 0, canvas.width, canvas.height);
+							ctx.translate(-x - width / 2, -y - height / 2);
 						}
+						ctx.drawImage(watermark, x, y, width, height);
 					}
+				};
+
+				let watermarkUrl: string;
+				if (config.fileUrl == null && config.fileId != null) {
+					const res = await misskeyApi('drive/files/show', { fileId: config.fileId });
+					watermarkUrl = res.url;
 				} else {
-					const x = (() => {
-						switch (config.anchor) {
-							case 'center':
-							case 'top':
-							case 'bottom':
-								return (canvas.width - width) / 2;
-							case 'left':
-							case 'top-left':
-							case 'bottom-left':
-								return 0;
-							case 'right':
-							case 'top-right':
-							case 'bottom-right':
-								return canvas.width - width;
-						}
-					})();
-					const y = (() => {
-						switch (config.anchor) {
-							case 'center':
-							case 'left':
-							case 'right':
-								return (canvas.height - height) / 2;
-							case 'top':
-							case 'top-left':
-							case 'top-right':
-								return 0;
-							case 'bottom':
-							case 'bottom-left':
-							case 'bottom-right':
-								return canvas.height - height;
-						}
-					})();
-					ctx.drawImage(watermark, x, y, width, height);
+					watermarkUrl = config.fileUrl!;
 				}
-			};
 
-			let watermarkUrl: string;
-			if (config.fileUrl == null && config.fileId != null) {
-				const res = await misskeyApi('drive/files/show', { fileId: config.fileId });
-				watermarkUrl = res.url;
-			} else {
-				watermarkUrl = config.fileUrl!;
+				watermark.src = config.__bypassMediaProxy ? config.fileUrl : getProxiedImageUrl(watermarkUrl, undefined, true);
 			}
-
-			watermark.src = config.__bypassMediaProxy ? config.fileUrl : getProxiedImageUrl(watermarkUrl, undefined, true);
 		}
+
 	};
 	if (typeof img === 'string') {
 		imgEl.src = img;
 	} else {
-		const reader = new FileReader();
-		reader.onload = () => {
-			imgEl.src = reader.result as string;
-		};
-		reader.readAsDataURL(img);
+		imgEl.src = URL.createObjectURL(img);
 	}
 }