yomichan/ext/js/media/media-util.js
toasted-nutbread 07df1e0117
Fix dictionary image support (#1526)
* Fix content security policy for images

* Add createBlobFromBase64Content to MediaUtil

* Update MediaLoader to use MediaUtil

* Use blob URLs when importing dictionaries

* Update VM's URL to support createObjectURL and revokeObjectURL

* Fix test
2021-03-14 18:41:15 -04:00

149 lines
4.8 KiB
JavaScript

/*
* Copyright (C) 2020-2021 Yomichan Authors
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/**
* MediaUtil is a class containing helper methods related to media processing.
*/
class MediaUtil {
/**
* Gets the file extension of a file path. URL search queries and hash
* fragments are not handled.
* @param path The path to the file.
* @returns The file extension, including the '.', or an empty string
* if there is no file extension.
*/
static getFileNameExtension(path) {
const match = /\.[^./\\]*$/.exec(path);
return match !== null ? match[0] : '';
}
/**
* Gets an image file's media type using a file path.
* @param path The path to the file.
* @returns The media type string if it can be determined from the file path,
* otherwise null.
*/
static getImageMediaTypeFromFileName(path) {
switch (this.getFileNameExtension(path).toLowerCase()) {
case '.apng':
return 'image/apng';
case '.bmp':
return 'image/bmp';
case '.gif':
return 'image/gif';
case '.ico':
case '.cur':
return 'image/x-icon';
case '.jpg':
case '.jpeg':
case '.jfif':
case '.pjpeg':
case '.pjp':
return 'image/jpeg';
case '.png':
return 'image/png';
case '.svg':
return 'image/svg+xml';
case '.tif':
case '.tiff':
return 'image/tiff';
case '.webp':
return 'image/webp';
default:
return null;
}
}
/**
* Gets the file extension for a corresponding media type.
* @param mediaType The media type to use.
* @returns A file extension including the dot for the media type,
* otherwise null.
*/
static getFileExtensionFromImageMediaType(mediaType) {
switch (mediaType) {
case 'image/apng':
return '.apng';
case 'image/bmp':
return '.bmp';
case 'image/gif':
return '.gif';
case 'image/x-icon':
return '.ico';
case 'image/jpeg':
return '.jpeg';
case 'image/png':
return '.png';
case 'image/svg+xml':
return '.svg';
case 'image/tiff':
return '.tiff';
case 'image/webp':
return '.webp';
default:
return null;
}
}
/**
* Gets the file extension for a corresponding media type.
* @param mediaType The media type to use.
* @returns A file extension including the dot for the media type,
* otherwise null.
*/
static getFileExtensionFromAudioMediaType(mediaType) {
switch (mediaType) {
case 'audio/mpeg':
case 'audio/mp3':
return '.mp3';
case 'audio/mp4':
return '.mp4';
case 'audio/ogg':
case 'audio/vorbis':
return '.ogg';
case 'audio/vnd.wav':
case 'audio/wave':
case 'audio/wav':
case 'audio/x-wav':
case 'audio/x-pn-wav':
return '.wav';
case 'audio/flac':
return '.flac';
case 'audio/webm':
return '.webm';
default:
return null;
}
}
/**
* Creates a new `Blob` object from a base64 string of content.
* @param content The binary content string encoded in base64.
* @param mediaType The type of the media.
* @returns A new `Blob` object corresponding to the specified content.
*/
static createBlobFromBase64Content(content, mediaType) {
const binaryContent = atob(content);
const length = binaryContent.length;
const array = new Uint8Array(length);
for (let i = 0; i < length; ++i) {
array[i] = binaryContent.charCodeAt(i);
}
return new Blob([array.buffer], {type: mediaType});
}
}