src/ui/component/publishForm/view.jsx

@@ -407,6 +407,7 @@ class PublishForm extends React.PureComponent<Props> {
               </header>
 
               <SelectThumbnail
+                filePath={filePath}
                 thumbnailPath={thumbnailPath}
                 thumbnail={thumbnail}
                 uploadThumbnailStatus={uploadThumbnailStatus}

src/ui/component/selectThumbnail/view.jsx

@@ -2,6 +2,7 @@
 import * as MODALS from 'constants/modal_types';
 import { THUMBNAIL_STATUSES } from 'lbry-redux';
 import * as React from 'react';
+import getMediaType from 'util/get-media-type';
 import { FormField } from 'component/common/form';
 import FileSelector from 'component/common/file-selector';
 import Button from 'component/button';
@@ -9,6 +10,7 @@ import ThumbnailMissingImage from './thumbnail-missing.png';
 import ThumbnailBrokenImage from './thumbnail-broken.png';
 
 type Props = {
+  filePath: ?string,
   thumbnail: ?string,
   formDisabled: boolean,
   uploadThumbnailStatus: string,
@@ -50,6 +52,7 @@ class SelectThumbnail extends React.PureComponent<Props, State> {
 
   render() {
     const {
+      filePath,
       thumbnail,
       formDisabled,
       uploadThumbnailStatus: status,
@@ -61,6 +64,8 @@ class SelectThumbnail extends React.PureComponent<Props, State> {
 
     const { thumbnailError } = this.state;
 
+    const isSupportedVideo = getMediaType(null, filePath) === 'video';
+
     let thumbnailSrc;
     if (!thumbnail) {
       thumbnailSrc = ThumbnailMissingImage;
@@ -141,9 +146,16 @@ class SelectThumbnail extends React.PureComponent<Props, State> {
           <div className="card__actions">
             <Button
               button="link"
-              label={__('Or enter a URL manually')}
+              label={__('Enter a thumbnail URL')}
               onClick={() => updatePublishForm({ uploadThumbnailStatus: THUMBNAIL_STATUSES.MANUAL })}
             />
+            {isSupportedVideo && (
+              <Button
+                button="link"
+                label={__('Take a snapshot from your video')}
+                onClick={() => openModal(MODALS.AUTO_GENERATE_THUMBNAIL, { filePath })}
+              />
+            )}
           </div>
         )}
 

src/ui/constants/modal_types.js

@@ -3,6 +3,7 @@ export const CONFIRM_EXTERNAL_RESOURCE = 'confirm_external_resource';
 export const INCOMPATIBLE_DAEMON = 'incompatible_daemon';
 export const FILE_TIMEOUT = 'file_timeout';
 export const DOWNLOADING = 'downloading';
+export const AUTO_GENERATE_THUMBNAIL = 'auto_generate_thumbnail';
 export const AUTO_UPDATE_DOWNLOADED = 'auto_update_downloaded';
 export const AUTO_UPDATE_CONFIRM = 'auto_update_confirm';
 export const ERROR = 'error';

src/ui/modal/modalAutoGenerateThumbnail/index.js

@@ -0,0 +1,16 @@
+import { connect } from 'react-redux';
+import { doHideModal } from 'redux/actions/app';
+import { doUploadThumbnail } from 'redux/actions/publish';
+import { doToast } from 'lbry-redux';
+import ModalAutoGenerateThumbnail from './view';
+
+const perform = dispatch => ({
+  closeModal: () => dispatch(doHideModal()),
+  upload: buffer => dispatch(doUploadThumbnail(null, buffer)),
+  showToast: options => dispatch(doToast(options)),
+});
+
+export default connect(
+  null,
+  perform
+)(ModalAutoGenerateThumbnail);

src/ui/modal/modalAutoGenerateThumbnail/view.jsx

@@ -0,0 +1,84 @@
+// @flow
+import React, { useRef } from 'react';
+import { Modal } from 'modal/modal';
+
+type Props = {
+  upload: Buffer => void,
+  filePath: string,
+  closeModal: () => void,
+  showToast: ({}) => void,
+};
+
+function ModalAutoGenerateThumbnail(props: Props) {
+  const { closeModal, filePath, upload, showToast } = props;
+  const playerRef = useRef();
+
+  let src = filePath.replace(/\\/g, '/');
+  src = src[0] !== '/' ? `/${src}` : src;
+  src = encodeURI(`file://${src}`).replace(/[?#]/g, encodeURIComponent);
+
+  function uploadImage() {
+    const imageBuffer = captureSnapshot();
+    if (imageBuffer) {
+      upload(imageBuffer);
+      closeModal();
+    } else {
+      onError();
+    }
+  }
+
+  function captureSnapshot(): ?Buffer {
+    const player = playerRef.current;
+    if (!player) {
+      return;
+    }
+
+    const canvas = document.createElement('canvas');
+    canvas.width = player.videoWidth;
+    canvas.height = player.videoHeight;
+    const context = canvas.getContext('2d');
+    context.drawImage(player, 0, 0, canvas.width, canvas.height);
+    const dataURL = canvas.toDataURL();
+    const rawData = dataURL.replace(/data:image\/\w+;base64,/i, '');
+    canvas.remove();
+    return Buffer.from(rawData, 'base64');
+  }
+
+  function resize(): void {
+    const player = playerRef.current;
+    if (!player) {
+      return;
+    }
+
+    console.log('resized');
+
+    const fixedWidth = 450;
+    const videoWidth = player.videoWidth;
+    const videoHeight = player.videoHeight;
+    player.width = fixedWidth;
+    player.height = Math.floor(videoHeight * (fixedWidth / videoWidth));
+  }
+
+  function onError(): void {
+    showToast({ isError: true, message: __("Something didn't work. Please try again.") });
+  }
+
+  return (
+    <Modal
+      isOpen
+      title={__('Upload Thumbnail')}
+      contentLabel={__('Confirm Thumbnail Upload')}
+      type="confirm"
+      confirmButtonLabel={__('Upload')}
+      onConfirmed={uploadImage}
+      onAborted={closeModal}
+    >
+      <section className="card__content">
+        <p className="card__subtitle">{__('Pause at any time to select a thumbnail from your video')}.</p>
+        <video ref={playerRef} src={src} onLoadedMetadata={resize} onError={onError} controls />
+      </section>
+    </Modal>
+  );
+}
+
+export default ModalAutoGenerateThumbnail;

src/ui/modal/modalRouter/view.jsx

@@ -4,6 +4,7 @@ import * as MODALS from 'constants/modal_types';
 import ModalError from 'modal/modalError';
 import ModalAuthFailure from 'modal/modalAuthFailure';
 import ModalDownloading from 'modal/modalDownloading';
+import ModalAutoGenerateThumbnail from 'modal/modalAutoGenerateThumbnail';
 import ModalAutoUpdateDownloaded from 'modal/modalAutoUpdateDownloaded';
 import ModalAutoUpdateConfirm from 'modal/modalAutoUpdateConfirm';
 import ModalUpgrade from 'modal/modalUpgrade';
@@ -51,6 +52,8 @@ function ModalRouter(props: Props) {
       return <ModalUpgrade {...modalProps} />;
     case MODALS.DOWNLOADING:
       return <ModalDownloading {...modalProps} />;
+    case MODALS.AUTO_GENERATE_THUMBNAIL:
+      return <ModalAutoGenerateThumbnail {...modalProps} />;
     case MODALS.AUTO_UPDATE_DOWNLOADED:
       return <ModalAutoUpdateDownloaded {...modalProps} />;
     case MODALS.AUTO_UPDATE_CONFIRM:

src/ui/redux/actions/publish.js

@@ -68,10 +68,22 @@ export const doUpdatePublishForm = (publishFormValue: UpdatePublishFormData) =>
     data: { ...publishFormValue },
   });
 
-export const doUploadThumbnail = (filePath: string) => (dispatch: Dispatch) => {
+export const doUploadThumbnail = (filePath: string, thumbnailBuffer: Uint8Array) => (dispatch: Dispatch) => {
-  const thumbnail = fs.readFileSync(filePath);
+  let thumbnail, fileExt, fileName, fileType;
-  const fileExt = path.extname(filePath);
+
-  const fileName = path.basename(filePath);
+  if (filePath) {
+    thumbnail = fs.readFileSync(filePath);
+    fileExt = path.extname(filePath);
+    fileName = path.basename(filePath);
+    fileType = `image/${fileExt.slice(1)}`;
+  } else if (thumbnailBuffer) {
+    thumbnail = thumbnailBuffer;
+    fileExt = '.png';
+    fileName = 'thumbnail.png';
+    fileType = 'image/png';
+  } else {
+    return null;
+  }
 
   const makeid = () => {
     let text = '';
@@ -102,7 +114,7 @@ export const doUploadThumbnail = (filePath: string) => (dispatch: Dispatch) => {
 
   const data = new FormData();
   const name = makeid();
-  const file = new File([thumbnail], fileName, { type: `image/${fileExt.slice(1)}` });
+  const file = new File([thumbnail], fileName, { type: fileType });
   data.append('name', name);
   data.append('file', file);