Since the start of digital video in 1988,
new video formats are developed every year in an attempt to provide improvements in quality,
file size and video playback. The popularity of video continues to grow
rapidly, with 78% of people watching at least one digital video on one of their devices
every single day; However video formats and how they work is still a subject of much confusion
for most people. Whether you need to convert your video file
to play in a specific browser or device, or you’re an editor looking to build your knowledge
on video formats in general, we’ll teach you the basics you need to understand video
files and how to use them to your advantage. In this video you’ll learn about the most
popular formats, codecs and containers for the web today, which parts they consist of,
and what format will be best for your situation. First we need to understand what a video format
is. Usually people refer to the file’s extension
as the video file’s format, but this isn’t entirely correct. Some formats consist as a combination of files,
folders and even playlists, all of which are needed to play the video properly. To better understand video formats, let’s
take a look at one specific video file and understand how all of it’s parts work together
to display the videos you see on your screen. The file extension is actually a representation
of what’s called the Container. A Container for a video file is the part that
contains all of the other files needed to play back a specific video. These files include the video stream, the
audio stream, and the meta data. This works with the video stream telling the
player what needs to appear on the screen while the audio stream tells the player which
sounds needs to be played alongside the video. The meta data, which means “data about data”,
includes all of the other information about the video, including things like the bit-rate
type, resolution, subtitles, device and time of creation, and more. One of the most important pieces of meta data
which you may have run into if you’ve worked with video files, is the codec. The word codec is a combination of the words,
coder and decoder. As the title suggests it creates an encoded
video or audio stream, making it smaller and easier to manage. The player or target software then decodes
it based on the rules set by that codec, and plays back the video with similar quality
to the original. Just like containers, there are hundreds of
different codecs used on various audio and video files. Companies like Qencode allow you to convert
your videos to the all latest codecs. Let’s cover the most important codecs for
you to use, as well as their advantages and disadvantages. Let’s start with the video codecs. A good place to begin is H.264, or AVC as
it’s commonly referred to. H.264 is by far the most commonly used video
codec, mostly because it provides a significantly better bitrate over it’s predecessors for
the same file size. For this reason, it is very widely supported
and you can be confident you will rarely run into any support issues using the H.264. It’s successor, H.265 is referred to as
HEVC which stands for High Efficiency Video Coding. This codec delivers on it’s name, with a
compression rate that is almost double that of H.264. This means the a file encoded with HEVC is
going to be at least 50% smaller than a file encoded in AVC. This is extremely beneficial for resolutions
above 2k as well as video streaming. The flip side of HEVC is that it’s much
more complicated to encode, requiring triple the resources for the video to be prepared
for playback. And just like H.264, H.265 is a proprietary
codec and has a royalty associated with it’s usage. Although adoption of HEVC is growing, after
3 years it’s still not nearly as popular it’s predecessor. Apple has recently announced that they will
support HEVC video, however there are some new codecs on the rise which give doubts as
to whether it will become dominant. For example, VP9 was developed by Google to
be a royalty free and open source codec. Originally it was used for YouTube, because
it also reduced bitrate 50% more that it’s predecessor, VP8. Just like H.265, it’s good for high resolutions
and live streaming, but is harder to decode and less supported than H.264. However, the technology behind VP9 generally
makes streams more consistent and reliable, while H.265 usually provides a better overall
image quality. It’s also important to note that VP9 commonly
uses the WebM or IVF containers, which we don’t have time to cover as part of this
video. A new royalty-free codec, called AV1, is currently
in development. Although it is still officially unreleased,
people who have started to use it say it shows a lot of promise. If wanna learn more, check out the link in
our description. We just covered the main video codecs you
need to think about, but audio codecs are a different story and also very important
to your video. Let’s take a look at some of the most popular
codecs for audio, to help you better understand which one best fits your needs. MP3 is one of the most famous audio codecs
out there. Developed by the Moving Pictures Experts Group
in 1993, this lossy audio codec takes advantage of the limitations of human hearing, often
referred to as auditory masking. An example of this is that an MP3 often is
reduced to 128 kbs, which sounds almost like the original CD but is only 9% of the size. 24 years later, mp3 continues to be a popular
format for sharing and playing back audio content, but it has limited functionality
for video and there are a few other audio codecs that have become increasingly popular
over the years. For example AAC, which stands for Advanced
Audio Coding, is a proprietary audio codec developed shortly after MP3. The main benefits of AAC are that it’s widely
supported and that you get better sound for the same bitrate. This has made AAC the most popular codec to
use for videos today. There are little support issues and most of
the time the is the best codec to use for your video, however AAC does have a limit
on audio channels, which means we will need another codec to handle more robust video
experiences. If you need surround sound or backwards compatibility
with Dolby products, AC3 may be the codec for you as it has a full range of channels,
allowing it to fully preserve surround sound settings. But aside from DVD players and digital television,
AC3 doesn’t have nearly the device support of AAC. There are other codecs as well, but currently
those are the most important for audio and video. Now that we know the basics, we can finally
talk about video file formats. File Formats are standardized rules for storing
the containers, codecs, meta data and sometimes even folder structure of video files, so that
it’s easier to support them across a large number of different devices and players. Since the very first digital video formats
became popular, new formats have been developed every year in an attempt to take their place
- aiming for improvements in image quality, file size, video playback, and the addition
of special features. A video format can become popular when a large
platform decides to support content with that format in their product, usually because of
a technological breakthrough or special use case. This often creates a self perpetuating adoption
cycle where creators produce more content in that format so that they can be compatible
with the large platform, which then makes other platforms support that format because
now there is so much more content being produced in that format. In this video we will teach you which video
formats are most popular today and which formats are best to use in certain situations. First of all, there are some formats that
are popular for video editing and others that are popular for online distribution. This is because editing videos generally demands
higher quality files while online distribution focuses on smaller file sizes and smoother
playback. For the purposes of this video, we’re mainly
covering online distribution to address the growing demand of on the internet. Also, stick around until the end of this video
for special tips getting the best quality from your YouTube uploads, by using the right
formats, codecs and settings. Let’s start by covering some of the most
popular formats. That first format we’ll look at is MP4,
more specifically MPEG-4, and even more specifically MPEG-4 Part 14. The name MPEG-4 can be very confusing because
different people use it for dozens of completely different things. The three most common things people mean when
they say MPEG-4 are: The MP4 Container (MPEG-4 Part 14), which
we are currently discussing The ISO Base Media File Format (MPEG-4 Part
12) used for video streams. The H.264 codec (MPEG-4 Part 10) is used to
compress video files. For the purposes of this video, we are talking
about the MP4 format, which is virtually synonymous with the container. MP4 is a great container for exporting videos
for the web, because of it exists in a single container and has wide support across devices
and operating systems. Due to the unpredictability of a user's internet
speed and growing demand of live streaming, a newer video technology, called adaptive
bitrate segmentation, has been growing in popularity of the last few years. Adaptive bitrate, commonly referred to as
ABR, works by converting a video stream into multiple resolutions, and splitting into several
smaller second clips with different bitrates. This clips can then be swapped between each
other if there are changes to the wifi or mobile network, preventing interruption of
playback while the user's internet catches up. In 2009, Apple developed HLS also known as
HTTP live streaming. It quickly became the most popular format
built on adaptive bitrate since delivering the clips over HTTP made it compatible with
a wide range of devices and firewalls. Unlike MP4, one of the key files in HLS is
the m3u playlist file, often called the manifest, with the extension .m3u8. which brings all
of these parts together. MPEG-DASH is another adaptive bitrate format
developed by the Motion Pictures Experts Group, and similar to HLS it uses the HTTP protocol. The main difference with DASH is that it’s
an open-source format and it was developed for global standardization, which it achieved
in 2012 when it officially became the first International Standard for adaptive streaming. Although HLS is still the most popular online
streaming format, MPEG-DASH is quickly catching up. The royalty-free approach was made it popular
initially, however this is still very good format to explore. This covers the most important formats, containers
and codecs for audio and video today. Let us know which combinations of formats
and codecs you’re thinking of using in the comments below! Do you already have a setup that is working
well for you? We’d love to hear from you. And now, on to our special tip: What video settings are best to upload a video
to YouTube to get the very result? If you have the option to export your videos
with any settings you choose, these are the settings you need to get the highest quality
from your videos on YouTube. First of all, the best format for a YouTube
upload is the MP4 container using the H.264 codec. Set the audio channel to Stereo or Stereo
5.1 with a sample rate of 96khz. Make sure your Aspect Ratio is 16:9 and your
frame rate is set to 60fps. If you can’t set your framerate that high,
choose the highest between 50, 48, 30, 25, or 24 frames per second. For bitrate, the best settings will depend
on a combination of resolution, frame rate and whether or not the video is HDR. Please use this graph to find the bitrate
setting ideal for your video. You can pause the video while you do so {short pause} The audio bitrate will depend on your channel
settings. For Stereo 5.1, set it to 512 kbps, for just
just stereo, set it to 384, and for Mono use 128 kbps. You can find all of this information, as well
as some more advanced settings in the Google Help Center. We’ll post a direct link in the description. If this video was helpful to you, please hit
the like button and subscribe to our channel for more interesting videos about digital
media technology. This video is brought to you by Qencode - the
better cloud video transcoding solution. Get 500 minutes free by visiting qencode.com
and utilize our highly scalable, low-cost, and fully customizable transcoding platform
for your business today. Also, be sure to check out some of our other
videos. Thank you for watching.
I skimmed through that, and it's a pretty good breakdown of the big mainstream codecs and containers.
However, I take issue with the YouTube export settings.
First: 96kHz is overkill. Most devices aren't recording 96kHz, some are even as low as 44.1kHz. Upsampling gets you nothing. Even in the pro world we stick with 48kHz and avoid resampling whenever possible.
Second: frame rate. There's no benefit to increasing your frame rate. You're doubling the amount of data you have to compress and store. Export at the frame rate you shot at, and if you do need to change the frame rate for whatever reason, it should be an even multiple of the frame rate you shot at, otherwise you risk creating weird motion effects.
Third: the bitrates seem a bit on the low for me. 15MbPS for 1080p60? I'd go at least double that, especially if it's true 60FPS material. Conversely, the audio bitrates seem overkill, but then again I'd just upload uncompressed PCM and call it a day.
Fourth: missing from the export settings is any mentions of Profiles or Levels, which can have a huge impact on quality at the same bitrate (or specifically Profiles will, and the Level will dictate if you can even use that bitrate). 1080p60 Baseline profile at 8MbPS would look like garbage compared to 1080p60 High profile at the same bitrate.
Fifth: there's also no mention of any editing codecs, which people would probably want to know about for editing in general. The video is useful for uploading to the Internet, but if you're needing to convert video because your computer can't handle it in the NLE it doesn't tell you much. Though not really a ding against it so much as a "maybe I would have included this too" bit.
I like to use 4 characteristics to describe digital video files:
Container (.mov .avi .wmv -- holds the codec). Some containers are more efficient or compatible than others.
Codec (instructions for compressing and decompressing video & audio, hence the name "codec"). Different codecs are used for various reasons, and settings within the codec can affect file size (and compatibility and whether it plays back correctly). Some codecs are more efficient than others (H.264 more efficient than MPEG2, for example: better quality in a smaller file size).
Frame size (the resolution of the frame, in pixels: 1920x1080, for example). The larger the frame size, the more pixels to keep track of (and typically proportionally related to file size, too). The smaller the frame size, less pixels to store. Aspect ratio is an element of frame size (4x3 vs 16x9, for example) and note that the pixels themselves aren't always perfectly square, depending on specifications of certain configurations.
Frame rate (how quickly the picture changes per second). Higher frame rates (60 fps) have more information than lower frame rates (12 fps, for example) and can affect file size. Also, it's a part of frame rate to note if the video is progressive or interlaced.
So using these four characteristics looks something like this: 1080i60 H.264 (.mov) which means 1920x1080 (16x9) frame size, 60 fields per second frame rate (30 interlaced frames per second ... actually 29.97 in North America but that's another story), using h.264 codec in a QuickTime (.mov) container.
Wow, that's a great analysis!
For the YouTube upload settings, all of this is taken directly from Google's own recommendations, found here: https://support.google.com/youtube/answer/1722171?hl=en
Regarding the Profile's and Levels, this is really good feedback. Never even considered it, definitely food for thought.
Regarding codecs and formats for video editing, there are some good videos on this already out there, not too many around the internet videos and codecs which people would be interesting in learning about.
We'll focus on putting more in-depth and recent for video editing formats and codecs as well. Thanks again for the great feedback!
I'm surprised he didn't mention mkv for video containers. Is that not a contender with mp4 these days?