diff --git a/src/settings/enums/ImageSize.ts b/src/settings/enums/ImageSize.ts
index 93cc2362737..1c2b8221048 100644
--- a/src/settings/enums/ImageSize.ts
+++ b/src/settings/enums/ImageSize.ts
@@ -20,7 +20,7 @@ const SIZE_LARGE = { w: 800, h: 600 };
 // For Normal the image gets drawn to never exceed SIZE_NORMAL.w, SIZE_NORMAL.h
 // constraint by: timeline width, manual height overrides
 const SIZE_NORMAL_LANDSCAPE = { w: 324, h: 324 }; // for w > h
-const SIZE_NORMAL_PORTRAIT = { w: 324 * (9/16), h: 324 }; // for h > w
+const SIZE_NORMAL_PORTRAIT = { w: Math.ceil(324 * (9/16)), h: 324 }; // for h > w
 
 type Dimensions = { w: number, h: number };
 
diff --git a/test/components/views/messages/MVideoBody-test.tsx b/test/components/views/messages/MVideoBody-test.tsx
new file mode 100644
index 00000000000..09d93f4d4a3
--- /dev/null
+++ b/test/components/views/messages/MVideoBody-test.tsx
@@ -0,0 +1,85 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from 'react';
+import { mount, ReactWrapper } from "enzyme";
+import { MatrixEvent } from 'matrix-js-sdk/src/matrix';
+
+import MatrixClientContext from "../../../../src/contexts/MatrixClientContext";
+import { RoomPermalinkCreator } from "../../../../src/utils/permalinks/Permalinks";
+import { MediaEventHelper } from "../../../../src/utils/MediaEventHelper";
+import { getMockClientWithEventEmitter } from '../../../test-utils';
+import MVideoBody from '../../../../src/components/views/messages/MVideoBody';
+
+jest.mock(
+    "../../../../src/customisations/Media",
+    () => {
+        return { mediaFromContent: () => { return { isEncrypted: false }; } };
+    },
+);
+
+describe("MVideoBody", () => {
+    it('does not crash when given a portrait image', () => {
+        // Check for an unreliable crash caused by a fractional-sized
+        // image dimension being used for a CanvasImageData.
+        expect(makeMVideoBody(720, 1280).html()).toMatchSnapshot();
+        // If we get here, we did not crash.
+    });
+});
+
+function makeMVideoBody(w: number, h: number): ReactWrapper<any, Readonly<{}>, MVideoBody> {
+    const content = {
+        info: {
+            "w": w,
+            "h": h,
+            "mimetype": "video/mp4",
+            "size": 2495675,
+            "thumbnail_file": {
+                url: "",
+                key: { alg: "", key_ops: [], kty: "", k: "", ext: true },
+                iv: "",
+                hashes: {},
+                v: "",
+            },
+            "thumbnail_info": { mimetype: "" },
+            "xyz.amorgan.blurhash": "TrGl6bofof~paxWC?bj[oL%2fPj]",
+        },
+        url: "http://example.com",
+    };
+
+    const event = new MatrixEvent({
+        content,
+    });
+
+    const defaultProps = {
+        mxEvent: event,
+        highlights: [],
+        highlightLink: '',
+        onHeightChanged: jest.fn(),
+        onMessageAllowed: jest.fn(),
+        permalinkCreator: {} as RoomPermalinkCreator,
+        mediaEventHelper: { media: { isEncrypted: false } } as MediaEventHelper,
+    };
+
+    const mockClient = getMockClientWithEventEmitter({
+        mxcUrlToHttp: jest.fn(),
+    });
+
+    return mount(<MVideoBody {...defaultProps} />, {
+        wrappingComponent: MatrixClientContext.Provider,
+        wrappingComponentProps: { value: mockClient },
+    });
+}
diff --git a/test/components/views/messages/__snapshots__/MVideoBody-test.tsx.snap b/test/components/views/messages/__snapshots__/MVideoBody-test.tsx.snap
new file mode 100644
index 00000000000..43b33baf82d
--- /dev/null
+++ b/test/components/views/messages/__snapshots__/MVideoBody-test.tsx.snap
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`MVideoBody does not crash when given a portrait image 1`] = `"<span class=\\"mx_MVideoBody\\"><div class=\\"mx_MVideoBody_container\\" style=\\"max-width: 182px; max-height: 324px;\\"><video class=\\"mx_MVideoBody\\" controls=\\"\\" controlslist=\\"nodownload\\" preload=\\"none\\" poster=\\"data:image/png;base64,00\\"></video><div style=\\"width: 182px; height: 324px;\\"></div></div></span>"`;
diff --git a/test/settings/enums/ImageSize-test.ts b/test/settings/enums/ImageSize-test.ts
index 55de23f9241..0eb89a45bba 100644
--- a/test/settings/enums/ImageSize-test.ts
+++ b/test/settings/enums/ImageSize-test.ts
@@ -38,5 +38,9 @@ describe("ImageSize", () => {
             const size = suggestedSize(ImageSize.Normal, { w: 642, h: 350 }); // does not divide evenly
             expect(size).toStrictEqual({ w: 324, h: 176 });
         });
+        it("returns integer values for portrait images", () => {
+            const size = suggestedSize(ImageSize.Normal, { w: 720, h: 1280 });
+            expect(size).toStrictEqual({ w: 182, h: 324 });
+        });
     });
 });