Encoding vs Encryption : What Is The Difference And What They Mean For Video Streaming?

Encoding and encryption are two techniques that play a crucial role in the transmission, exchange, storage, and creation of digital content be it plain text or rich media. Encryption employs an algorithm that takes in either plain text or metadata of rich media and converts it into a pseudo-random string of hexadecimal called a hash. Hash is incomprehensible unless decrypted with a private key. Your passwords, credit card numbers, WhatsApp messages, and Facetime calls all are converted to a hash before being transmitted to the network.   

Encoding is required because the format you capture content in and the format it is received in may vary since web services and OTT platforms often encode the content at the time of transmission. Encoding serves two purposes: it saves bandwidth at both recipient’s and transmitter’s end and addresses incompatibility issues at the receiver’s end. Upon reaching the recipient’s end, the web service leverages inbuilt decoders to recreate the media on the target device. 

The encoding requires just a decoder while encryption required a private key in addition to a decrypter.  

Here in this blog, I’ll explore encoding vs encryption, what they mean and how do they work in terms of video streaming

Encoding vs Encryption in Video Streaming 

Encoding and encryption are two of the standard techniques that video platforms employ to ensure safe and efficient delivery of the content over the network. While the two techniques have multiple overlaps over how a video is encoded or encrypted, they serve two very different purposes. The purpose of encoding is to encode a RAW video in a particular codec to ensure its efficient delivery over the network and playback support on the target device. Encryption, on the other hand, ensures that the video is not playable to anyone other than its intended audience. If you have ever heard of DRM, you know what I am trying to imply here. 

What is Video Encoding? 

Video production has various stages to it: production, post-production, publishing, distribution, and release. The color grading and video editing tools your post-production team may have access to might not read RAW video clips coming out of your production cameras.  

“A RAW image represents RAW data coming out of the camera’s image sensor. It is equivalent to image-negative in analogue cameras” 

The post-production team must encode the video in a compatible format. Likewise, the video format the publisher distributed the content in may not be practical for end-user consumption. It might be consuming too much bandwidth or perhaps the quality is taking too much of a hit. Maybe, the target device doesn’t have the decoder to playback the received, encoded video for end-user consumption. 

Encoding is all about overcoming the friction that arises between the various stages (and teams) of video production.  

Encoding is essential to video production because every team in the funnel have different expectation from the received video file. Post-production wants quality while distribution expects the video to be portable.  

Video encoding ensures that your video is converted from raw format to all the relevant format for video streaming.

The Role of Codecs in Encoding 

Video footage that hasn’t been encoded to a codec is considered RAW. RAW footages are perfect for production because they are virtually lossless. One downside is an hour RAW 4K footage may occupy a couple of terabytes on your disk. If your post-production team isn’t onsite, you may wish to encode the RAW file in one of the professional codecs such as ProRes 4K before sending them over. Encoding a RAW video file to a professional codec compresses its size. Quality loss from encoding RAW footage to a professional codec is, generally, considered nearly lossless. That is, the encoding loss is indecipherable to human eyes.  

The footage undergoes encoding once again–this time to one of the consumer codecs. Consumer codecs have a higher compression ratio than professional codecs and thus are apt for end-user consumption. 

The Role of Video Decoders 

Any video encoded to a video codec is only playable on a device that has decoders for the codec built-in. Many hardware vendors include specialized hardware to accelerate the decoding process. For example, modern Apple devices contain a dedicated decoder for HEVC (or H.265) acceleration.  

When releasing a video to the end-users, the distribution platform has to ensure that it is encoded in a codec that the devices and browsers they are targeting have encoders for. In the case of Netflix, it encodes HDR videos in two consumer codecs HEVC and VP9 because Chrome OS and Android don’t have HEVC decoders. 

What is Video Encryption? 

While encoding concerns every stage of video production, the role of encryption role is restricted to the distribution phase alone. Video distribution is a risky business considering how much money video distribution platforms pay to grab the rights to an upcoming web series or movie. Video distribution platforms rely on subscription and rental fees to cover those costs and make the business sustainable. Piracy is a mean business. Anybody can illegitimately make copies of a video and illegally distribute it over a P2P network.  

The question is: If a piece of content is available freely on the internet, why would anybody pay for it? 

Encryption ensures even if somebody could make a copy of the video, it wouldn’t of much use to the person trying to play it back. Just as encrypted messages are hashed and thus aren’t readable to anybody other than their intended recipients, an encrypted video copy wouldn’t be of much use to anybody without its private key. 

How Does Encryption Work? 

Every time you request a copy of a video, either from a streaming service like Disney Plus or a video rental platform such as iTunes, you are asked to log in with your username and password. Once you have done that, the video platform encrypts the video with your credentials as the private key before start streaming or downloading it to your device.  

Standard encryption techniques employ two sets of keys. A private key that is only available to you and must be kept secure all the time, and a public key for the distributor to validate that you’re the intended recipient.  

Public key generated from the private key through a method called cryptography and employ one of the many available cryptographic algorithms. Cryptographic algorithms such as AES are irreversible that is anybody can generate public keys from their private key but not vice-a-versa. AES is one of the methods streaming platforms employ to enforce DRM on their content. 

In the case of video encryption, the private keys are often tied to the credential you use to log in to the streaming service. There is a reason you cannot play movies you rented from services like Amazon Video and iTunes while not logged in to your account.  

Encoding vs Encryption: Similarities and differences 

Video Encryption and encoding might seem like similar techniques on the surface. In fact, you essentially encode a file to a key in the process of encryption. Encryption makes the file indecipherable without a key while encoding makes the video file unreadable with the relevant decoder. Both encryption and encoding require specialized software and hardware to happen. Decryption and decoding software is built into every other general-purpose operating system such as macOS, Windows, and Android. 

However, once you dive deeper the similarities begin to fade away and we see a clear distinction. As I said, encryption is for the security of the content while encoding is for its transmission. Of course, a premium video must be encrypted before transmission. Therefore, encryption and encoding take place at the same time. That is when an end-user requests the content. 

Any decoder for a codec can playback the video if it was encoded in it. In the case of encryption, not any decoder but that equipped with your private key can.   

The Role of DRM in Video encryption 

Digital Right Management (or DRM) serves a two-fold purpose in the video distribution market. It prevents unauthorized distribution of premium video content in the first. Then, it restricts the ways people can copy the content they have acquired. DRM is the reason you’re returned a blank screen when you try to screenshot Netflix. It is DRM that makes it impossible to download videos on Hulu. Streaming platforms employ either AES or  DRM to protect their content. Widevine DRM and Fairplay DRM are two widely used DRM.

Advanced Encryption Standard (or AES) is the most popular methods video production studios use to protect their content from unauthorized access. Most streaming protocols such as HLS, Smooth Streaming, and MPEG-DASH support AES out of the box. 

Encode and Encrypt With VdoCipher

Encoding and Encryption is something for which you need a bit of technical knowledge to get sorted. When encoding and encrypting your videos in bulk you might need a complete video infrastructure. But setting up your own infrastructure can be labor, cost, and time-consuming. The best and the easiest way is to opt for a service that already has that infrastructure set and you can save a lot by using their services. This is where VdoCipher comes in, we take care of encoding to ensure that your video files are encoded and transcoded to all the relevant formats. Also, that your video is encrypted and the encryption key is not accessible by any unauthorized person. This ensures that your videos are compatible with all the browser and apps, also that they can’t be downloaded.

Vdocipher provides DRM-based encryption with Widevine DRM and Fairplay DRM. On top of it you get various other video hosting features such as Video API, Powerful CDN, Video Analytics, Dynamic watermarking,  Screen recording protection on iOS and Android.

Which is more important: Encryption Vs Encoding? 

At the time, when video-on-demand (VoD) services such as streaming and video rental platforms are giving broadcast media a run for their money, encryption and encoding techniques will play an even larger role to keep the business sustainable for the stakeholders.  

It is hard to say what is more important. If you would talk to someone at YouTube, they would say it is a business of encoding. YouTube relies on ad revenues to fund its video sharing platform and encryption doesn’t play a major role. Google would rather invest its manpower in improving the current codecs and streaming methods to be more efficient. So that they can secure more video streaming channels for the same amount of bandwidth.  

However, streaming platforms that rely on a paid subscription to run their platform would put more insistence on encryption. Did you know Netflix paid a billion-dollar to CBS to retain the rights to Friends? That is every time somebody is watching Friends on their local media player is actually taking a pie from Netflix’s annual revenue, making the business slightly less sustainable for the leading video streaming platform. It would be natural for Netflix to invest its resources in techniques that would make copying video from its library even harder.  

Well, what is more important, encryption or encoding, comes down to the revenue model of the distribution platform.  

Yet it would be advisable to give both of them equal importance. Your business model may change (or perhaps evolve) in the future. Sometime back YouTube started offering premium content to its paid customers. A few streaming services started offering an ad-supported tier on their platform in addition to paid plans.  

Encryption vs Encoding isn’t a debate but a conscious choice to protect your interests and that of your users.