Do we always have to cater to the lowest common denominator in terms of inbound available bandwidth? The answer is you can push multiple bit rates, and in the next article in this series we discuss multi-bitrate streams MBR as well as adaptive bit-rate ABR and look at the pros and cons of these different approaches.
Next Read Part 3. Drivers of Quality Now, what are the primary drivers of quality? Expectation of Quality The quality expectation of your stakeholders is primarily a function of the video culture within your organization and depends on how expectations around video have been set in the first place.
Back to Blog Home Related Posts. Next - Microsoft Teams Live Events vs. But, like many other types of content, the video must be of superior quality to attract clients to your project. This is where the biggest misconception takes place, because many people find the resolution to be almost the only important video quality indicator, excluding many other factors, like video bitrate. The higher the bitrate, the sharper the video image, which is especially crucial when you prepare for live broadcasting.
When being published on different video hosting sites, like Vimeo or YouTube, the video gets compressed, hence bitrates are reduced.
This may result in poor image quality, but only if you are not familiar with bitrate yet. Simply put, video bitrate defines video data transferred at any given time.
A high bitrate is doubtlessly one of the most crucial factors in the quality of a video. Together with a satisfactory bitrate value, high resolution and frame rate contribute to a good-looking video. Otherwise, they have little effect on the way it looks. Videos of any length and size require much more data to use than, say, high-res photos or regular email.
To reach the audience with distinctive content on a live broadcast platform or video hosting site, make sure the data transmission is fast enough. When talking about video in broadcasting, data transmission is explained through uploads and downloads. Uploading means the data is transferred from your remote device to the web after you send the video signal to the encoder for data compression.
Downloading, in its turn, illustrates the process when users receive the video to their devices from the web. Regardless of the transfer types, we measure their speed using bitrates. A higher transfer speed involves more data to pass through, whereas a higher bitrate results in better-quality video. Avoid mixing up Mbps and MBps, which mean different things.
Megabits Mbps per second refers to uploading and downloading speed, while megabytes MBps per second is used to define the wealth of info transferred. Broadcasting is doubtlessly an effective method to connect with the audience. But, what is the key to producing a professional-looking live video? Some might say it is the gear you use. This is for another topic. The size width and height and shape ratio between width and height of a video can vary widely depending on the intent, meaning the size and shape can change depending on where the creator intends it to be displayed.
The intent could be a Television in someone's home, or via the Internet, or even something like a Jumbotron in Times Square. Today, televisions throughout the world use the standard window sizes known as High Definition or HD. The window size for those are pixels wide x pixels high, or pixels wide x pixels high, respectively. A pixel is the smallest dot on a screen that is made up of a red, green and blue light source.
Most videos uploaded to the Internet usually follow these same television standards. Both of these window sizes have an aspect ratio of , spoken as 16 by 9.
This is the ratio of width to height of the video image, or the shape of the rectangle you view. Sometimes this is called Widescreen , and was adopted to more closely mimic the movie theater experience for home viewers.
Anecdotally, the original standard definition aspect ratio of was adopted in the s to mimic the movie theater experience of that era. When televisions became a more common household appliance, the theater industry moved away from the aspect ratio to other wider formats in order to entice viewers to come back to the theaters. A new emerging standard for televisions called 4k is coming fast. They have screens that can display 4 times the resolution of p HD. Currently the standard for television networks and local affiliate stations to broadcast Over-The-Air OTA is only HD and cannot support 4k at this time.
Taking an example from Wikipedia's article on motion compensation , let's say this is your original frame:. The encoder now only stores the actual differences, not the pixel-by-pixel values. This is why the bits used for each frame are not the same every time. These "difference" frames depend on a fully encoded frame, and this is why there are at least two types of frames for modern codecs:.
You occasionally need to insert I-frames into a video. The actual bitrate depends also on the number of I-frames used. Moreover, the more difference in motion there is between two subsequent frames, the more the encoder has to store. A video of "nothing" moving will be easier to encode than a sports video, and use less bits per frame. I believe your math is actually correct, but there is a little more to it; compression is the missing link here.
You calculated the uncompressed bit rate, and came up with the reason that compression exists. The bit rates become impossibly large with uncompressed video. So, they compress the video at the source, and uncompress it at the receiver, and then the bit rate becomes manageable. You just need a fast enough decompressor, which may be hardware or software.
So, the issue becomes how much compression can be tolerated - it's not lossless, usually, so you are losing information, but they try to make it intelligent enough to lose the less important data that won't be so noticeable. It usually is fairly easy until there is a lot of motion, then it becomes more complicated. Edit: Forgot to add, but the parts that implement the compression method is the codec; I noticed that you used this as a tag in your post. Sign up to join this community.
The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How does bitrate differ for the same resolution and framerate? Ask Question. Asked 9 years, 6 months ago. Active 6 years ago.
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