captions

Normal

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Zoltán

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Tutorials

Add captions to your videos hosted at api.video using the standard WebVTT format and enable your audience to have seamless user experience regardless of their language or location. Captions also enable you to provide more inclusive and accessible content by inviting deaf or hard-of-hearing users into your audience.

## How to upload captions

api.video offers a suite of dedicated API endpoints that can help you manage captions for your videos programmatically. You can also use the api.video Dashboard to upload captions directly to any of your videos.

### Via the API

The `/captions` API endpoint enables you to manage captions for your videos.  You can upload, update, get, list, and delete captions.

When uploading captions, you only need to include 3 attributes in a `POST` request to the [Captions endpoint](https://docs.api.video/reference/api/Captions#upload-a-caption):

- the `videoId` of the video that you want to add a caption to,
- the `language` of the caption you want to upload,
- and the path to the caption’s VTT `file` that you want to upload.

### Via the Dashboard

If you need a quick no-code solution to upload captions to a video, check out your list of uploaded videos [in the Dashboard](https://dashboard.api.video/videos). Open the Details page of the video that you want to add a caption to and click on the Captions tab to upload VTT caption files manually.

A screenshot of the api.video dashboard showing the Caption menu.

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## Selecting caption languages

When uploading captions via the API, you need specify the caption file’s language using [IETF language tags](https://en.wikipedia.org/wiki/IETF_language_tag). You can use primary subtags like `en` (English), extended subtags like `fr-CA` (French, Canada), or region subtags like `zh-Hans-CN` (Simplified Chinese used in the PRC). api.video's caption solution supports all major and minor languages, and even dialects.

Check out the documentation for a [complete list of supported language tags](https://docs.api.video/vod/add-captions#supported-caption-language-tags).

## What is WebVTT?

WebVTT is a standard format for displaying timed text tracks for captions or chapters. It is a text based format, which must be encoded using UTF-8. Here’s an example:

Check out the [Mozilla developer guide](https://developer.mozilla.org/en-US/docs/Web/API/WebVTT_API) for more information about WebVTT.

## Best practices

- When uploading a caption file, make sure that you use the standard VTT file format.
- To ensure that you use the correct formatting in your VTT file, api.video recommends using a parser to check for errors before you upload the file. [Click here](https://w3c.github.io/webvtt.js/parser.html) for a free online VTT parser.
- You can upload captions for one language, and to one video at a time.
- api.video offers video player SDKs for the most popular platforms - and apart from the Flutter player, all of them support captions! Check out the [Player SDKs](https://docs.api.video/sdks/player) to get started!

## Next steps

Now that you understand how captions work at api.video, check out this earlier blog post about [adding captions programmatically to your videos](https://api.video/blog/tutorials/how-to-add-captions-to-your-videos/), or dive into the [documentation](https://docs.api.video/) to understand more about api.video’s solutions.

Lost in translation? Fill in the blanks with captions!

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Doug Twitter

Doug Sillars

Videos are a compelling way to share experiences with your customers. The combination of speech, sounds, images and movement allow us to share a more enriching experience.

However, on the web a video can only be autoplayed when it is muted. As a consumer with small children, this is often a blessing: the last thing I want is a website to wake up a sleeping baby. But as a developer, I want everyone to experience everything my videos have to offer, so I want to work around this issue (but of course, while still letting everyone’s babies nap!)

One solution is to add captions. Users can still engage with your video and follow along with the dialogue. Facebook finds that [videos with captions are watched 12%](https://instapage.com/blog/closed-captioning-mute-videos) longer than videos without captions (85% of Facebook videos are watched without audio). Longer video watch time increases [your search rank](https://www.3playmedia.com/2018/12/10/7-ways-video-transcripts-captions-improve-seo/), and the presence of a captions file even improves your site SEO! With all of these advantages, the accessibility improvements of your website almost come as an afterthought.

No matter the reason you choose to add captions to your videos — you are probably wondering how it is done!

## The VTT File

Closed captioning is typically done with a VTT (Video Text Track) file. They=se are text files that simply list the text that should appear over a specified period:

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In the example above, from 15–17.9 seconds, the text “At the left we can see” will appear on the screen, followed a split second later by “at the right we can see.” It is really a pretty straightforward format. But other than manually transcribing your video, how can you create a VTT file?

Let’s walk through 2 ways:

### VTT Creator

[VTT Creator](https://www.vtt-creator.com/) is a web based tool. You simply upload your video, and as it plays the video back, it creates captions for you.

![](https://cdn-images-1.medium.com/max/800/0*0EV4F_2lV2epjlaB)

The website uploads your video and begins the analysis, and the pane on the left fills with the subtitles

![](https://cdn-images-1.medium.com/max/800/0*XTOA3ZQoSjDk3InB)

You can download the VTT, and you’re good to go!

### Google Speech to Text

Google Cloud, Azure and AWS all have a speech to text tool. I chose Google’s for this demo, but they all operate in much the same way.

Google has a helpful [QuickStart](https://cloud.google.com/speech-to-text/docs/quickstart-client-libraries#client-libraries-install-nodejs) guide to set up your Google Cloud account for Speech to Text. The first step is to use ffmpeg to strip the audio track (there is no need to upload the video track when doing audio analysis).

I used their Node.js code example with a few changes (Code available on [GitHub](https://github.com/dougsillars/subtitles)). The video I was transcribing was over 1 minute long, so I had to host it on a Google Cloud instance. Rather than using:

There is no need to transcode the video to base64 (as described in the tutorial) if it is hosted on Google Cloud. The sample code from Google writes the transcript into the console:

![](https://cdn-images-1.medium.com/max/800/0*PHDqyWCU_PCA4nR8)

This is super cool, but we want more than a transcription — we need those time stamps. The raw JSON file has an entry for each word with the start and end time for each word:

![](https://cdn-images-1.medium.com/max/800/0*jxIPZw0Mr2CFOVLA)

So I created a function that groups words, using the first word’s start time,and the end time of the last word. The length of the phrase can be varied — in the sample code it is set to 10 words. The script outputs a VTT file to the console.

### Adding Captions to your Video

### HTML5

Adding the VTT file to your video is easy. If you are using HTML5 video, you can add a track attribute pointing to the VTT file.
```html
<video autoplay muted controls>
    <source src=”myvideo.webm”>
    <source src=”myvideo.mp4">
    <track default lang=”en” kind=”captions” src=”myvideo.vtt”>
    <track lang=”es” kind=”captions” src=”muvideo-es.vtt”>
</video>
```
### Video Streaming

If you want to add captions to your [api.video](https://api.video) video, you can use the Captions API.

1.  First you must [authenticate](https://api.video/blog/tutorials/authentication-tutorial/) your session to gain an access token.
2.  Determine the videoID of the video you’d like to add the caption to. In this example, I have created captions to [Elephant’s Dream](https://orange.blender.org/) (an Open Source video project). The video ID is: vi5UNyaStzuuj0xTAGp7qtjf

(https://embed.api.video/vod/vi5UNyaStzuuj0xTAGp7qtjf)

3. Make a call to add the [caption](https://docs.api.video/reference/api/Captions#upload-a-caption). Using curl, the request looks like:
```bash
curl [https://ws.api.video/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/en-US]
(https://ws.api.video/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/en-US) -H ‘Authorization: Bearer {access\_token}’ -F file=@/path/to/google.vtt
```

And we receive a response:
```bash
{“uri”:”/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/en”,”src”:”https://cdn.api.video/vod/vi5UNyaStzuuj0xTAGp7qtjf/captions/en.vtt","srclang":"en","default":false}
```

Note that captions are off by default. This is easily resolved by patching the video, setting the default to true. Using curl, this looks like:
```bash
 curl -X PATCH [https://ws.api.video/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/en](https://ws.api.video/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/e) -H ‘Authorization: Bearer {access\_token}’ -d ‘{“default”: true}’
```

And we receive a response:
```json
{
  “uri”:”/videos/vi5UNyaStzuuj0xTAGp7qtjf/captions/en”,
  ”src”:”https://cdn.api.video/vod/vi5UNyaStzuuj0xTAGp7qtjf/captions/en.vtt",
  "srclang":"en",
  "default":true
}
```

And watching the movie: success! the captions are turned on by default. To autoplay a video with api.video, simply add #autoplay to the end of the url, and we have an autoplaying video with captions.

Now we can rest assured that our videos will likely have more traction, be watched longer, and shared more often. And, we are making our content more accessible to users who cannot hear.

### Conclusion

Video captions not only make your content accessible, but research shows videos with captions are watched longer, and shared more often. And searchable transcriptions actually increase the SEO of your site!

Often there is reluctance to add captions due to the added work, but with just a few clicks of a button, captions can be generated automatically and uploaded for immediate playback.

[Give it a try](https://dashboard.api.video/register), and share your caption successes on the [api.video community forum](https://community.api.video/).

How to add captions to your videos

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Erikka Innes

If you are creating captions for your videos, sometimes the captions don't appear where you want. Maybe they don't sit on the screen correctly, or maybe you have a creative way you want to present them. As it turns out, captions are adjustable! It will take some fine tuning to get the hang of working with them, but WebVTT is easy to use.

## Prerequisites

For this project you need: 

* api.video account - [Sign up here!](https://dashboard.api.video/register)
* A video you want to caption, uploaded to api.video - [here's a blog about how to upload your video](https://api.video/blog/tutorials/upload-a-video-with-the-api-video-python-client/)
* A VTT file for your video - [Learn how to caption a video with Maestra](https://api.video/blog/tutorials/add-captions-to-your-video-with-maestra-and-api-video/)

## Moving captions

To move captions, open your VTT file. You'll see captions listed next to their times, like this: 

`00:00:01.000 --> 00:00:02.000 
Hello World!`

Now let's say you don't like where the caption starts from. You can add on to the end to move it horizontally. Like this: 

`00:00:01.000 --> 00:00:02.000 position: 20%
Hello World!`

The screen is divided into percentages, so if you put a lower percentage, your caption moves further to the left. If you choose a higher one, it moves further to the right. Be careful you don't move captions into positions where they can't be seen. 

You can also make the captions go vertical. For that, you'd add: 
`00:00:01.000 --> 00:00:02.000 position: 20% vertical:rl
Hello World!`

And in this case, the position is vertical, so the percentage represents a portion of the vertical. 

You can learn a lot more about how to move captions and what's possible by checking out the [WebVTT Guide](https://www.w3.org/TR/webvtt1/). Just a few things you can do include changing the color of text, adding italics, specifying if something is loud, and much more!

How to edit and style your video captions

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Captions increase your video's audience. Viewers spend more time watching captioned videos, many people watch videos with the sound off, and you can draw viewers who don't speak the spoken language of your video if you include subtitles. See ["Why You Should Caption Your Videos, Whether They're Classes, Speeches, or Entertainment"](https://api.video/blog/video-trends/why-you-should-caption-your-videos-whether-they-re-classes-speeches-or-entertainm/) if you want all the details and statistics for why you should consider captions for your video content. Another great reason to add captions, is it's easy to do with api.video and Maestra! Let's get started. 

## Prerequisites

* [api.video account](https://dashboard.api.video/register)
* Maestra account (click the blue **Get Started Free** button)
* Sample video with spoken audio (we used one of Doug for this - https://www.youtube.com/watch?v=O3C7_kgwrPY, but any video is fine as long as it has clear audio) 

Maestra, auto captions, subtitles, caption a video, subtitle a video

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1. Click **New Subtitle** to bring up the upload panel.
2. On the upload panel under Upload your files, click **My Device**. 
3. For the Select audio language section, we choose **English** because the video is in English. The drop-down offers a 'Most Used Languages' section and an 'All Languages' section. 
4. You can choose different settings. For this walkthrough, we choose **Translate captions to another language** and then for the target language, choose **Spanish**. If you want different settings you can put those instead. 
5. Click **Submit**. 
6. Your video will start transcribing. Once it's complete, click on the title of your video. You can see how well your transcription came out. In this case, it came out pretty well.

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7. The next step is to export a copy of the file with the captions we want. Click the **Export** button in the upper right corner. You'll get a screen listing various choices, including downloading a video with all your captions included. We just want to get a WebVTT file for this walkthrough.
8. Make sure you are on the **Subtitle** tab. 
9. Under Languages, check the **English** and the **Spanish** box. 
10. Click **WebVTT** to download your caption file. The first time you click it, it will say **Ready**. The second time, it downloads a **.zip** file with your information in it. 
11. When you open the **.zip** file, you'll see a caption file in English and one in Spanish. Save these. 

## Add the Video to api.video
We need to add our video to api.video before we can caption it. You have a few choices available to you: 

* [Delegated Uploads for Videos Large and Small](https://api.video/blog/tutorials/delegated-uploads-for-videos-large-and-small-python/) - This tutorial shows you how to use a delegated token to upload a large or small file using Python.
* [Upload a Video From Your Computer](https://api.video/blog/tutorials/upload-a-video-from-your-computer-with-the-api-video-api-python/) - Upload a video under 128 MB from your computer using Python. 
* [Upload a Video with the api.video API Using a Public URL](https://api.video/blog/tutorials/upload-a-video-with-the-api-video-api-using-a-public-url-python/) - Transfer a video from a public URL to api.video

You can also use a no-code method:

1. Open the api.video dashboard.
2. Click **My videos**.
3. Click **Upload**. 
4. Add your video. 

## Use the Captions Endpoint to Add Captions to Your Video
We can now take the files Maestra generated for us and add them to our video. Here's the code sample we're going to use to do it: 

The code sample hard codes the videoId - but if you want you can retrieve it programmatically. A design where a VTT file's title somehow matches the video's title and then you grab the videoId might be a good way to go. 

In our demo, everything is set up to try to handle a situation where you have multiple caption files. We assume a naming convention like this: 
```title_language tag.vtt``` 

So samples of this would be: doug_en-GB for English from Great Britain and doug_es-ES for Spanish from Spain. 

The language tag in each case is a BCP 47 tag. The appropriate tag is at the end of each file so that it can be sliced from the file name and used in the caption upload. Using Python's regex and os modules we search for every file in the current directory that ends with '.vtt'. If it ends with this, we then retrieve the language tag from the end of the title, open the file in binary, then append the tag and file to a POST request to add a caption. We also modify the URL - it needs to include the videoId and the language tag for the language we want to add. You can see how that's built in the sample.

We have two caption files, so we loop through our .vtt files and send each one to be added. For each successful addition of a caption file, we get a response that looks similar to this: 

```
{
	'uri': '/videos/vi6FZib80ZrC8q73AekJqNDH/captions/es', 
	'src': 'https://cdn.api.video/vod/vi6FZib80ZrC8q73AekJqNDH/captions/es.vtt', 
	'srclang': 'es', 
	'default': False
}
```

* uri - the unique link that you add to ``` https://ws.api.video ``` to reach the video caption file (you must authenticate to view this, so you can't paste it into a browser to see it) 
* src - the location URL of the file
* srclang - what language you're using, written shorthand (instead of es-ES it would be es) 
* default - whether this is the default language for the video 

If you want to make a particular language the default caption, you can specify the language by updating a caption. 

## Check Your Work
You can retrieve details about your captions, but an easy way to check is to look in your dashboard: 

1. Go into your Videos section and click your video.


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2. Click the **Captions** icon directly under the X. You'll see that you can add English or Spanish captions. Give it a try on your own video! 

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Maestra does fairly well with captions, as long as the audio is clear. They offer a free trial for up to 30 minutes of video, so try them out yourself. Maestra lets you automatically create a variety of caption files, but api.video uses the WebVTT format, so you'll want that for any projects on our platform. 

If you want to create your own WebVTT file from scratch, Doug wrote a great post about how to do this here: [How to Add Captions to your Videos](https://api.video/blog/tutorials/how-to-add-captions-to-your-videos/)

## Show a Caption
You can see if a caption was already added with this code: 

## Show All Captions
If you want to see every caption for a video, you can do this: 

## Delete a Caption 
A caption can be removed with the following code: 

## Update a Video Caption
You can update a video caption to make it the default. The code for that would be: 

This is all the basics for using captions. Thanks for tuning in today! 
[Start builind now](https://dashboard.api.video/register)!

Add Captions to Your Video with Maestra and api.video

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Video trends

Captions are required for any content that's aired on TV before. The 21st Century Communications and Video Accessibility Act (CVAA) makes this a requirement for any online video that's previously appeared on TV. You'll notice that your favorite streaming sites, like Hulu, Netflix, Amazon, and others all provide captioning for their content. Look around a bit more, and you'll see that these sites often caption all their content even if it's not required. That's because there are additional benefits to video captioning beyond just meeting legal requirements. 

## Statistics That Will Make You Want to Caption Your Content
If you want to reach viewers, captions rule. In fact, Digiday said "85% of Facebook video is watched without sound." If there's a message you're trying to convey that requires more than images, captions are what will make this possible. 

Statistics about captioning, captions, video

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Verizon Media has a similar statistic - they say "69% view video with sound off in public places and 25%  watch with sound off on private places." And that's not all. According to the same study done by Verizon Media, 80% of consumers are more likely to watch an entire video when captions are available and 50% of consumers say captions are important because they watch video with the sound off. 

So while your video or live stream may not end up on TV and require captioning, including captions increases your chance of reaching viewers. What makes no sound so important to viewers? Well as it turns out, there's a few common reasons they might need or prefer captions.

## Watch Without Sound 

watch a video without sound, captions for silent video, captioning

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Captions help the deaf watch video content that might not have been accessible to them otherwise. However, captions can do more than that. For people that hear, they may find themselves in a situation where they want to watch a show, but they don't have a way to control the sound with headphones or similar. In a situation like this, turning the sound off and reading captions can still allow them to watch their shows. Even if they can control sound with headphones, they may be in too noisy a situation, or a situation where they need to listen for certain cues - like somebody waiting for their flight in an airport. 

## SEO 

Boost SEO with captions, caption a video, captioning

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If you include a transcript of your video with your video description, search engines will crawl it. This can result in a better SEO rank than just posting the video alone. If you've posted a class of some kind, including the transcript can help people search for the part of the video they wanted. There are even some tools out there that will highlight the chunk of the transcript that matches what's being said in the video. Viewers can click around on the transcript to move the position in the video forward or backward. A great example of this can be seen on Coursera classes. 

## Increase Audience Comprehension
Captions help people more fully understand what's happening in a video. It can help someone taking an online class retain information or it can help someone better follow the plot of their favorite show. When it comes to entertainment like movies or television, captions can make viewers more aware of the music selected for a scene by including the sung lyrics. Frequently show creators choose music to underline a key theme or plot point. Seeing the lyrics can help make viewers more aware of the subtleties of what they're watching. 

## Draw Viewers Who Speak Other Languages
Subtitles are a type of caption, and when you include them you make your content more globally accessible. You can more easily reach viewers in their native language, and subtitles help you achieve that affordably. Completely dubbing content into another language requires voice actors and careful automated dialogue replacement (ADR). Adding captions makes your video accessible without all of this effort - you only need a good written translation instead. 

## Add Captions to Your Content Today
api.video allows you to caption all your video content using our Captions endpoint. Create a Web Video Text Tracks (WebVTT) file by hand or with an online tool to get started. Then upload it for your video and voila! your video content can start reaping the benefits of captions today. 

We have a tutorial to help you get started - [How to Add Captions to your Videos](https://api.video/blog/tutorials/how-to-add-captions-to-your-videos/)
[Start building now](https://dashboard.api.video/register)!


Caption your videos (classes, speeches, or entertainment)

Why you should caption your videos, whether they're classes, speeches, or entertainment

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Delegated Upload

Video Status

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NodeJS

Video captions/subtitles make it easier to follow along with your video. Whether your users have hearing issues or not, sometimes they may not want to have a loud speaker playing the video's audio, and adding captions allows them to understand the video.


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When adding captions to a video, you must create a WebVTT file. We've [written on the process of creating WebVTT files](https://api.video/blog/tutorials/how-to-add-captions-to-your-videos/). The format is not difficult to understand, but they are not simple to create manually, you need to break up a transcription into segments, and add start and stop times for each section.  


```

3
00:00:07.519 --> 00:00:11.759
The little train rumbled over the tracks.

4
00:00:10.880 --> 00:00:15.279
She was a happy little train for She had such

5
00:00:13.439 --> 00:00:16.719
a jolly load to carry.

6
00:00:15.599 --> 00:00:20.480
Her cars were filled full of good things for boys

7
00:00:18.879 --> 00:00:21.199
and girls.

```



In this post, we'll show how using the [Authot](https://www.authot.com/) transcription APIs can help you automatically add video captions to your videos, without the fuss of manually creating the VTT caption file.

Authot will receive the video file, make a transcription of the audio file, and then return a complete webVTT file. api.video can then ingest this file into the same videoID as the video, and the captions are added to the video.

It sounds like magic! To prove that it actually works, we've built a demo application [caption.a.video](https://caption.a.video) that utilizes api.video and Authot to host, stream and auto-caption your videos.  

## How it works

The first step is to upload your video to api.video.  This demo is built on top of a [delegated token upload](https://api.video/blog/product-updates/video-access-management-how-to-create-deliver-and-manage-private-videos-and-what/), meaning that a temporary public token was created that lets us upload right from the browser.



### Upload complete

Once the video is uploaded, api.video begins transcoding into a HLS sstream and an MP4 version of the movie.  To create a transcription, Authot requires the mp4 file, so the application uses the [video status](https://docs.api.video/reference#get-video-status/) endpoint to determine when the mp4 video has been encoded. This endpoint tells us when each video stream is ready for playback. Once the mp4 is encoded, we can submit the file to Authot for transcription.

### Transcription

Once the video has been submitted to Authot, the API returns the ID number of the transcription.  The Status endpoint tells us what state the transcription is in.  

The initial state is 0: Uploading

The final state is 10: transcoded

There are some states in between, including 2: transcribing

### Getting the WebVTT

Once the transcription is complete, (when Authot returns the status "10"),  the Node server requests the VTT file, and then uploads the file to the existing video at api.video.

### Completed

The webpage finally updates the text, saying "success".  Clicking the video link - opens the video, and the user can enable captions and watch them play back.


## Automatic captions!

Of course, automatic captions are not 100% accurate.  You may have a few words incorrectly transcribed.  However, in my testing the Authot API is pretty good, and the captions are of a very high quality.

On the other hand - manually creating captions will either take a lot of time, or cost a lot of money (to pay someone else to do the work).  The ease of use, and low cost makes auto-captioning a compelling choice


## Conclusion

We've described an application that allows you to upload a video and automatically add captions to the video.  Try it out today at [caption.a.video](https://caption.a.video). If you're curious on how we built this app, the code is available on [Github](https://github.com/dougsillars/captionavideo).  Let us know what you think by posting on our [community forum](https://community.api.video/).

Add captions, and watch your video watch time increase!

Auto Caption a video

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Authenticate

Captions allow hearing impaired users to read the words being said in your video. It also improves watch times, and can improve your SEO.

To add captions to your video, you'll need a VTT file for a video already uploaded to api.video.
> [Learn how to create a VTT Video Caption File](https://api.video/blog/tutorials/how-to-add-captions-to-your-videos/)

>[Video Upload Tutorial](https://api.video/blog/tutorials/video-upload-tutorial/)

> Find all details to display your captions in [our docs](https://docs.api.video/reference/api/Captions#retrieve-a-caption)

## Authenticate your session
You will need your API key to obtain the access_token. You can find your API key in [your dashboard](https://dashboard.api.video/login).

First, call the authentication endpoint and get your access token.

Example - Curl Request

replace {videoId} with the videoId of the video to receive captions; {lang} with the language of the video (ex: en-US for US english); and {access_token} with your access token.

### JSON response

### Make captions default

The JSON response above shows that by default, captions are off.  To add them, send a PATCH update command:


## Conclusion

Captions make it easier to watch a video. Not just for hearing impaired users, but for autoplaying videos that begin muted. You users can just read what is happening without sound, and then, if they are interested can un-mute the video. You can also add internationalization by translating the captions to additional languages.

Let us know how you are using captions in our [developer community](https://community.api.video). Happy building!

Adding captions

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Product updates

At api.video, our goal is for video to be easy and affordable for anyone to build, be it individuals or organizations. We understand that achieving this goal means reducing costs at some stage of the video streaming process. That’s why, we now offer adaptive bitrate encoding for your videos at zero cost. 

&nbsp;

Yes, you heard me right. 

&nbsp;

**Encoding videos will be absolutely free for all video qualities (1080p or 4K) at [api.video](https://api.video/) - no hidden calculations, footer notes or tricks.**

(Check out this [video](https://www.youtube.com/watch?v=ouosgLbW7Ts) for more details) 


## A step towards making video streaming affordable

Video encoding is crucial as it makes it possible for videos to be shared and played smoothly on the internet. It is why we are easily able to consume various types of video media, whether it’s a YouTube video, our favorite shows on Netflix, or even catching up with friends across the globe on Zoom. Video encoding basically makes the world go around in regards to anything related to video and video content.

&nbsp;

We at api.video recognize that. From [increasing the transcoding and playback speed ](https://api.video/blog/product-updates/2021-in-review/)to building [specialized hardware like ASICs](https://api.video/blog/video-trends/the-comeback-of-specialized-hardware/) cards to increase our transcoding capacities, we've been working to make video streaming easier for you every day. And after dedicating ample time to engaging with our customers and learning about their concerns, free encoding seemed to be the next step in this direction. 

&nbsp;

So, we worked tirelessly behind the scenes to give you what no one else will - free encoding for all video qualities, be it 360p or 4K. 

## How does free video encoding benefit you as a customer

The benefit is straightforward: you save a LOT of money!

&nbsp;

- With free video encoding, you will have one less thing to worry about. As you know, you pay for three things for streaming videos — encoding, hosting, and delivery – out of which encoding is the most expensive, especially if you have a lot of videos. Free video encoding will allow you to focus your attention and resources to what is most important.

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- As the video needs of your app users grow, you might need to scale up your encoding capacity. Free video encoding services will give you the power to scale without any additional costs, meaning your users can handle more videos without increasing your expenses.

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- You can [migrate from your previous provider to api.video](https://api.video/compare/azure-media-services/) without paying an ‘entry tax’ to us. With free video encoding, you no longer need to spend money on encoding videos with a new provider when you have already paid for encoding with an older one.

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Now with all the saved cost, you can allocate your resources and money to a place where it is actually important – building your product and delighting your users. 

## How to get started

To use the free video encoding benefit, getting started is easy. 

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- If you’re a new user, [sign-up](https://dashboard.api.video/register) for a free sandbox account and start uploading your videos
- If you are looking to migrate from another vendor, [import](https://import.api.video/) your videos from your current vendor
- If you have any questions, [talk to us](https://meetings.hubspot.com/apivideo/talk-to-us) by booking a slot in our calendar

&nbsp;

To know more about our[ features](https://api.video/features/), [pricing](https://api.video/pricing/) or ask any other questions, [talk to our team ](https://meetings.hubspot.com/apivideo/talk-to-us)and we will help you out. 

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Or, you can straightaway [sign-up](https://dashboard.api.video/register) for a free sandbox account and check our product out for yourself. 


Huge pricing update: Introducing video encoding at no cost

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Modern technology has been helpful for an increasingly fast and simple method of consuming various types of video media, whether it’s a YouTube video, our favorite shows on Netflix, or even catching up with friends across the globe on Zoom. Despite the relative ease of doing anything related to video, a few complex processes take place behind the scenes, away from public view. One such process is video encoding.

Video encoding basically makes the world go around in regards to anything related to video and video content. Thanks to the technologies behind the video encoding process, it has become much easier for people and companies to share video content on the internet. But what exactly is video encoding, and what happens during the process? We’ll take a closer look at this and much more in this handy guide to video encoding.

## What is video encoding?

In a nutshell, video encoding occurs when you take raw video footage, either from a digital camera or an analog film camera, and digitally compress it to make it a more manageable file size. Video encoding happens daily in both professional and personal capacities, and many people don’t realize it.

But, without encoding, services like Netflix and YouTube would not exist – or, at least, not in the same way that it does today. Without it, we couldn’t send videos of our beloved pets to our friends and family as easily as we can today.

## Why is video encoding used?

There are a variety of reasons why video encoding is used, but all factors point to the single function of video encoding – **compression**.

This is done to ensure optimal performance and compatibility with a selected suite of software and hardware, be it for DVD/Blu-ray playback, mobile viewing, online video streaming, or general video editing. A file's video and audio information undergo transformation and compression during the encoding process, all in accordance with the requirements of the selected encoding standard.

On a professional level, the ability to compress raw video into more manageable sizes makes it easier to transmit video content such as training, promotion, presentation, and so on over the internet. 

On a personal level, video encoding makes it much easier to send videos taken from your phone directly to friends and family. Most modern-day personal devices have built-in video encoding capabilities to allow for this to happen without a second thought.

To put things in perspective, uncompressed or unencoded video can have a data rate that’s as low as 3,000 Mbps and as high as 12,000 Mbps, depending on the length and quality of the video recorded. 

**Without encoding, it would take up to days for anyone to not just transmit video, but to be able to consume it, too.**

## Differences between video encoding and video transcoding

You need to be familiar with two more [essential terms related to video encoding](https://api.video/what-is/) – transcoding and codecs.

Transcoding relates to the conversion from one digital encoding format to another. It takes the already encoded video file, decompresses it, and then alters it before re-encoding or compressing it into a different codec. Codecs are what allow encoding to occur in the first place. They are software or hardware that gives us the ability to compress video to make them more easily stored and delivered tightly.

While you may hear “encoding” and “transcoding” used interchangeably, the two terms actually mean different things. Putting it succinctly, encoding is the initial process of compressing a video from a source – such as a camera – into a codec, while transcoding takes an already encoded video file to convert it into a different codec.

## Examples of video codecs

In order to understand video encoding, you must first be familiar with two interrelated terms: [video codecs and video formats](https://api.video/blog/product-updates/every-video-format-codec-and-container-explained/). These also tend to be used interchangeably, but much like the terms encoding and transcoding, they refer to two different things.

Video formats are the type of files in which the compressed video/audio is stored. Also known as a “container”, you can tell what a video format is by looking at the file’s extension — the three to four characters that sit after a period in a file name. Here are some of the most common video formats used today:

* MP4
* FLV
* MOV
* MKV
* LXF
* MXF
* AVI
* WebM
* QT

On the other hand, **the codec is short for “Coder / Decoder” (compression / decompression)** and relates to the video compression algorithms that allow encoding to happen. Over the years, codecs have gone through multiple iterations as it coincides with the increasing sophistication and rise in the quality of filmmaking. 

If you’re a content creator, you might be aware of some of the video codecs that exist today:

- **H.264 – also known as AVC, this is the most widely-used video codec available on every platform and mobile device.**
- H.265 – also known as HEVC, stands for High-Efficiency Video Coding, and it’s slowly overtaking H.264 as the standard. This codec can compress video much more efficiently than its predecessor.
- **VP9 – is an open-source, royalty-free codec developed by Google and is considered the direct competitor of H.265. The video compression codec VP9 was created to reduce file sizes, making streaming videos simpler.**
- **AV1 – is another royalty-free, open-source codec released in 2019 by the non-profit Alliance for Open Media. It was developed to become the successor to Google’s VP9 and contend with HEVC more directly.**

## How do different technologies handle video encoding

As you may have suspected, there are a majority of ways that different technologies handle the video encoding process. Let’s take a look at the most common technologies that use video and how video encoding works on each of them:

### Video editing software

When it comes to video content creation, a majority of people will use one of two video editing software — Adobe Premiere Pro or Apple’s Final Cut Pro. Both of these video editing software handle video encoding in very similar ways: when exporting the finished video.

Depending on which device the video content is recorded on, it will already be encoded and formatted according to the settings of the device. For those using iPhones recording 1080p video at 25 frames per second (FPS), for example, the iPhone will automatically encode the video using H.264 and contain it in a .mov file format. The video editing software will “open up” the container to get to the encoded, compressed video file within so the editing process can begin.

After editing the footage is complete, it will need to be exported, which typically concerns video encoding. The edited raw media taken from a recording device such as a camera will be encoded via the codec of the person’s choosing before being put into a .mp4 container once they’ve hit “export”. As we’ve mentioned before, the most common codec used in video content creation is H.264 for HD videos, with 4K videos using H.265. 

### Websites

Different websites utilize different techniques to handle video encoding – with a majority of the major sites like YouTube, Netflix, and so on using their own technologies to handle the process. A majority of social media websites allow you to upload video files directly onto the site to share, although most of them require the files to be saved in specific containers. 

These websites will take your video file and transcode it before using their own systems and serves to re-encode it to match multiple display resolutions. This process will happen regardless of your video file's original codec and settings. Different websites have different processes, but companies that don’t have the capacity to build their own video encoding systems can use a third-party application programming interface (or API) to handle this process. These APIs act as [dedicated video encoder](https://api.video/what-is/video-encoding/) that allows companies to add on-demand videos to their websites more efficiently.

Using [api.video](https://api.video) as an example, all of the videos submitted to the platform will be transformed into H.264 codec in an MP4 container. This may be done using transmuxing and/or transcoding.

We expect the video bitrate to be lower than 16 Mbps for up to 1080p resolution and 50 Mbps for up to 4K resolution. We accept any bitrates, however, we will scale them down to the limits mentioned because anything above is usually challenging for most viewers’ connection to watch.

### API

The ability to generate, store, and distribute video is made possible via a video API. [api.video](https://api.video)’s solution can be tailored to suit any specific need. 

The backend process of video on demand (VOD) is exceptionally complex, even if you’re a software programmer specializing in video. It is necessary to encode, package, and typically transcode the data before sending it to any of several possible destinations. All of these things, and more, may be done with minimal fuss using api.video.

Our API basically keeps the complexities of streaming media hidden from view, so you can rapidly develop apps with as much control as you need. This saves time and effort so developers can concentrate on making the product.

## Conclusion

As you can see through this video encoding guide, a lot of work goes into making the video you watch and the video you share possible. Without video encoding compressing raw video footage, it could take days to upload and transmit video content over the internet and perhaps even longer to be able to download and enjoy them. 

The best part about encoding at api.video is that is offered at ZERO cost. You will only be charged for delivery and hosting of your videos, and the encoding will be free. Now integrate your videos in minutes with api.video or [contact us](https://api.video/contact/) for more information.

A Guide to Video Encoding & Video Codecs

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Encoding and transcoding are often used interchangeably but they have slightly different definitions. **Encoding is the initial process of converting raw video files into a specific digital format or codec.** It involves compressing and packaging the video data, often to reduce file size while maintaining acceptable quality. Encoding prepares the video for storage, transmission, or playback.

&nbsp;

**Transcoding, on the other hand, involves converting a video from one digital format or codec to another.** This is typically done to optimize the video for different devices or platforms, adapt to varying network conditions, or ensure compatibility with specific playback requirements. Transcoding occurs after encoding and often involves changing resolution, bitrates, or formats without altering the content itself.

## What goes on behind encoding a video?

It's easy to say that encoding is when you go from an _uncompressed source_ to a _compressed source_, but you may ask, what exactly do compressed and uncompressed sources mean?

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Uncompressed sources are video files that contain data that comes directly from a camera sensor vs. encoded video. In the digital space, it's SDI (Serial Digital Interface) or HDMI (High Definition Multimedia Interface). Both of them are popular standards. You'll find HDMI in places like your GoPro camera, or a mini camcorder. These days, you might also find HDMI in professional settings, but SDI is more common due to its reliability. Another example of an uncompressed source would be something analog, for instance, VHS tapes.

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A compressed sources, on the other hand, are video files that have undergone compression during the encoding process. Compression involves reducing the file size by removing unnecessary information or encoding the data in a more efficient format. This process results in a smaller file size, making it more manageable for storage, transmission, and playback.


## What are the types of transcoding methods?

There are three types of transcoding, depending on what you are trying to do to get a video to suit a particular browser, player, or platform:

* **Lossless-to-lossless** - This type of transcoding maintains the quality of your video across formats but allows you to take advantage of better hardware or compression algorithms. 
* **Lossless-to-lossy** - This type of transcoding will decrease your video in quality, but it will benefit you in ways such as – you will get a smaller and/or faster playing file, or a file that is compatible with the requirements of a particular platform, player, or browser.
* **Lossy-to-lossless** - Sometimes people think this means they are regaining quality. This isn't the case in this type of transcoding. If you transcode from a lossy format to a lossless format, all that it means is that you will not lose additional quality in the conversion process. You will not regain data you already lost through compression.

## Codecs for encoding and transcoding

For both encoding and transcoding, you will need to make use of codecs. A codec's job is to compress and decompress video files. It's right there in the name -  **co**mpress **dec**ompress or encode decode. So basically, codec is an algorithm that takes the video and shrinks it or changes it into a format that makes it compatible with the requirements of wherever you want the video to play. There are many codecs because there are many ways to compress a video or livestream for playback.



## What is transmuxing?

Now that you know the difference between encoding and transcoding, let's throw one more term in there - transmuxing. Transmuxing is when you change the container for a video instead of the format. It's a way of repackaging a video to make it compatible somewhere without changing what's in the file. 

&nbsp;

This process is faster than encoding or transcoding and takes less computing power because you only change the container, not the file. It's great when you need to quickly make something available, but the downside is that it doesn't handle things like making multiple video resolutions available. If you choose a container type that's incompatible with your video file, you may also cause compatibility issues, resulting in not being able to play the video.

## In closing

* **Encoding** - Encoding happens when you compress a raw data file from a video camera sensor or an analog source like a VHS tape. 
* **Transcoding** - Transcoding happens when you take an already compressed video file and change it to another format.
* **Transmuxing** - Transmuxing happens when you change the container of a video file but leave the video file untouched. 

We hope that explains the difference between encoding and transcoding clearly. 

_If you are looking for an affordable video API solution that does not burn a hole in your pocket for transcoding and encoding videos, check out our offerings on our [homepage](https://api.video/) or [sign-up for a free account here](https://dashboard.api.video/register)!_

Encoding and transcoding: what's the difference? 

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Once I upload my video, how quickly will it be ready to be viewed?

Our reply to this question has always been “it's really fast.”  And it is really fast. But, the dev team gave me access to the backend database, and pointed me to a few tables that might be helpful (thanks to Thomas Persohn for your patient help!)

Thus armed, I waded into a sea of data to better understand how fast our videos are encoded at api.video

## Encoding

When a video is uploaded to api.video, it is re-encoded to a HLS stream, with several different video dimensions and bitrates.  This allows api.video to deliver properly sized video to all users - no matter the device or network connection. (Read our post on [Responsive video delivery](https://api.video/blog/video-trends/responsive-video-delivery/) to learn more.)

> Summary:  All videos are encoded at 240p, 360p, 480p, 720p, 1080p and 2160p. However, the videos are only encoded up to the initial size of the video (so if the original video is 720p, there will not be 1080p or 2160p versions available). 

**FYI:** For our customers, encoding is absolutely free – we offer adaptive bitrate encoding at zero cost. 

How long does this step take? If a customer uploads a video to our service - they want to know how efficient api.video creates the content for viewing.

### Data in the study

We are constantly making adjustments to our infrastructure to speed the encoding step of our video (and that is one reason this post is dated 2H 2020 - we expect to be faster in early 2021). The last major adjustment was made in mid October, so the data presented in this study from every video uploaded to the api.video service between 15 October and 2 December 2020.

### Parameters that affect encoding

There are 2 major parameters that affect the speed of encoding a new video stream: the output dimensions and the length (duration) of the video.  

#### Dimensions

The output video dimensions have a huge impact on video creation - a 3840 × 2160 (or 4K or 2160p) video has millions more pixels than a 320x240 (240p) video, so it takes a lot longer to create.  In general, the videos exit the encoding process from smallest to largest.

#### Duration

If a video is 30 frames per second, and is 60 seconds long, there are 1800 frames to be created.  If a 30 frame per second video is an hour long 3600s), there are 108,000 frames to be created, so the longer the video - the more time for creation.

## Analysis

To better understand the encoding time, I divided the data by the size of the output video size, and looked at 2 lengths of video  - those under 5 minutes, and videos that are 45-75 minutes long (we are often asked how long a 1 hour video takes to encode).

I calculated encoding time for each bucket of video using percentiles.  

> Quick review - percentiles break the data into 100 evenly sized segments, so the 25th percentile is when 25% of the videos have been encoded. The median is the 50th percentile, and is when 50% of videos have been encoded.  We report here to the 95th percentile for video encoding.

### Short videos - under 5 minutes long

Many of the videos uploaded to api.video are short - under 5 minutes long.  These videos are generally ready to play in a few seconds:



The above chart has a lot of data, the 25, 50, 75, 90 and 95th percentile encoding times for all 6 variants of the video that api.video creates.

The median video is ready to play (at 240p) in 5.6 seconds, but a 720p version will be ready in 15s after encoding begins, and the 4K version will be ready in 37 seconds.

95% of all videos (under 5 minutes) will be playable in 32.6s, and will have 1080p versions ready in just over 2 minutes (140s).

### Long videos - 45 - 75 minutes long

Our most frequently asked question on encoding is "how long for a 1 hour video to be encoded and ready?"  Here are the numbers:


Observant viewers will see there are no 4K videos in this report. At this time, there are very few 4K streams that reach the 1 hour timeframe, and the data was quite noisy.  Hopefully, more of our 'long uploads' will add 4K support, so we can add this metric in our next update.

The median hour long video (red line) will be ready to play (at 240p) in just over 9 minutes (555s), and a 720p version will be ready about 18 minutes after encoding begins (1099s).

95% of hour long videos will have a 240p version ready in 33 minutes, and 720p in 54 (3230s).  the 1080p version will be available for 95% of videos in 108 minutes,

## Conclusion

Short videos will be ready to play - even at high resolution - in under a minute: the median 4K encoding for a short video is 37s. 

Hour long videos take longer to encode, and the median 720p video will be ready in 18 minutes.  95% of 720p videos will be ready to play in 54 minutes.

This is really fast! You can have responsive streaming video ready for your customers in just a few minutes with a simple upload!

That said, our team is working hard in the background to improve our infrastructure to make our encoding speeds even faster! 

We're really excited to have hard numbers to share with you on our encoding speeds, and we cannot wait to re-benchmark this data in 2021 to see how much faster your videos will be encoded as we improve our service.

Do you have questions about api.video or video encoding? Reach out on our [community page](https://community.api.video).


How fast does api.video encode video? 2H 2020 data

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Huge pricing update! Introducing video encoding at zero cost

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