Functions

VOD ingests media files and transcodes these files for playback on a wide range of devices. It is widely used for online education, web portals, social networking, and catch-up TV. Table 1 describes the functions of the VOD service.

**Table 1** Functions
Category	Function	Description
Media upload	Formats	Supported video formats: MP4, TS, MOV, MXF, FLV, MPG, WMV, AVI, F4V, M4V, HLS, and MPEG Supported audio formats: MP3, OGG, WAV, WMA, APE, FLAC, AAC, AC3, MMF, AMR, M4A, M4R, WV, and MP2
	Upload methods	Media files can be uploaded through the console. Three upload modes are available: local upload, pull from URLs, and OBS hosting. A PC batch upload tool is provided to migrate media files from the local PC or OBS to VOD. Currently, the tool is available in Windows and Linux. APIs for file upload and server SDKs in Java, Python, Go, Node.js, .Net, and PHP languages are provided.
	Upload rules	Each video file is split into multiple small files (20 MB by default) and uploaded to VOD. The timeout interval for uploading a small file is 60 minutes.
Media management	Category management	You can create categories and manage uploaded audio and video files by category.
	Thumbnail management	The first frame of video can be taken automatically as your video thumbnail. You can also upload a thumbnail in JPG or PNG format from your local PC. You can take a snapshot and save it as your video thumbnail.
	Subtitle management	You can upload SRT subtitle files in UTF-8.
	Video publish	After a video is published, a specific URL is generated. Your users can watch the video through the URL.
	CDN pre-loading	You can pre-load media files on your domain name to CDN nodes for a better playback experience.
Media processing	Transcoding	Supported input file formats: MP4, TS, MOV, FLV, MPG, MXF, WMV, ADTS, AVI, MKV, and MPEG Supported video codecs: H.264, H.265, MPEG-2, MPEG-4, MJPEG, WMV1/2/3, and ProRes 422 Supported input audio codecs: AAC, AC3, EAC3, HE-AAC, MP2, MP3, PCM (s161e, s16be, s241e, s24be, DVD), and WMA Supported output file formats: DASH, HLS, MP4, MP3, and ADTS Supported output codecs: H.264, H.265, HE_AAC, AAC, and MP3
	Video watermark	You can add watermarks in PNG, JPG, and JPEG formats to videos. The maximum size of a watermark is 100 MB.
	Audio extraction	You can extract audio from video files and save it as MP3 format.
	Snapshot capturing	You can take snapshots from videos and save them as JPG files. By interval: Take snapshots at regular intervals. The default interval is 12s. At fixed time: Take snapshots at specified time points.
	Packaging	Packaging only changes media format without changing the resolution and bitrate. You can: Package media files in FLV and HLS formats into MP4. Package media files in MP4, FLV, and MP3 formats into HLS.
	Content moderation	The system checks the compliance of uploaded media files.
Media acceleration and playback	Custom domain name	The configured VOD domain names can be used for media file distribution acceleration.
Media acceleration and playback	Hotlink protection	You can configure referer validation and URL validation to protect your resources to be distributed.
Security management	Referer validation	You can configure referer blacklist and whitelist to control who can or cannot access your VOD resources and to prevent hotlinking.
	URL validation	You can configure the key to control who can or cannot access your VOD resources and to prevent hotlinking.
	HLS encryption	HLS videos can be encrypted using AES128 to prevent VOD resource leakage and link theft.
	HTTPS secure acceleration	HTTPS secure acceleration is supported. Forcible redirection to HTTPS and HTTP 2.0 is supported.
VOD console	Dashboard	You can view data such as VOD resource usage. You can change the CDN billing option.
	Media file management	You can transcode, pre-load, categorize, export, and delete media files, and cancel transcoding. You can extract audio from video files. You can upload a thumbnail and subtitles for a video file. You can view the audio and video playback addresses, subtitles, and thumbnail information.
	Video Processing	You can take snapshots from videos. You can select a workflow to process media files.
	Content Moderation	The system checks the compliance of uploaded media files.
	Audio and Video Uploads	Audio and video files can be uploaded from your local PC or obtained from the URL.
	Statistics	You can view resource usage on CDN and your origin server, and view most requested content.
	Global Settings	You can configure transcoding templates, watermark templates, HLS encryption, notifications, and workflows.
	Domain Name Management	You can add your own domain name, and configure the CNAME, HTTPS secure acceleration, and hotlink protection for the domain name.
	Audio and Video Hosting	You can authorize VOD to host media files in your OBS bucket and use transcoding and frame capture to process these files.
	Short video	You can purchase, download, and manage short video materials, including themes, filters, stickers, subtitles, transition effects, and particle effects.
VOD APIs	Media upload	APIs for media file upload are available, including local upload, replicating files from OBS to VOD, OBS hosting, and pull from URLs.
	Media management	APIs for querying, publishing, canceling, deleting, and modifying media are available.
	CDN pre-loading	A media pre-load API is provided to prefetch media files by ID or URL.
	Media processing	APIs for video processing (transcoding, snapshot capturing, and HLS encryption), thumbnail setting, and media file review are available.
	Categorization	APIs for creating, deleting, modifying, and querying categories are available.
	Statistics	APIs for querying CDN statistics, VOD origin server statistics, and most requested content are available.
	Key query	The HLS encryption key can be queried.
VOD SDKs	Server SDK	Functions such as media upload, processing, management, pre-loading, and distribution are available.
VOD SDKs	Short video SDK	The Android and iOS short video SDKs are provided to support HD recording, multi-track and multi-segment editing, filters, animation, and stickers.