What is video bitrate
Is higher bitrate better? The Comprehensive Guide to Video Bitrate: What It Is, How Bitrate Affects Video Quality, Video Bitrate Comparisons, and More!
Video bit rate refers to the data flow used by video files per unit time, also called bit rate. The larger the bit rate, the larger the sampling rate per unit time, the higher the accuracy of the data stream, and the effect shown in this way is: the video picture is clearer and the image quality is higher.
Bit rate calculation method Bit rate (kbps) = file size (KB) * 8 / time (seconds). In this example, the capacity of the video file is 3.446G, and the video length is 100 minutes (6000 seconds). The calculation result is: bit rate It is approximately equal to 4818kbps (3.446 * 1024 * 1024 * 8 / 6000 = 4817.857).
The role of the bit rate The larger the bit rate, the greater the sampling rate per unit time, the higher the accuracy of the data stream, and the effect shown in this way is that the video picture is clearer and the image quality is higher. When the video is encoded and compressed, the bit rate may be reduced. If the bit rate is too low, mosaics will appear in the picture, that is, the color scale of some areas in the picture will deteriorate, and the color confusion will cause the details to be unclear (such as crimes in the news. Avatars of suspects are often used). This is because each pixel needs to retain the corresponding information, and after reducing the bit rate, the information it retains is correspondingly reduced, and the pixels without information can only share information with the surrounding pixels, so that the color will appear chaotic and the picture will be blurred. Terrible. But in the case of a constant bit rate, we can avoid mosaics by reducing the resolution, that is, the number of pixels in each frame, because the fewer pixels, the less need to share pixels for rendering.
what is bit rate
A few weeks ago I had a question what is bitrate?
When you use Adobe Premiere Pro, Final Cut Pro, or other editing software to export video, does the following happen?
I just wanted to explain to you in a very basic sense what is bitrate and
what is bitrate?
Bit rate refers to the amount of data encoded in the video per second, ie the video bit rate
The audio bit rate has nothing to do with the video resolution, but they will be encapsulated in the same file, that is, compressed
What does all this mean now? Meaning the higher the bitrate of your video, the higher the quality of your video. On the other hand, the higher the bitrate, the larger the file size of your video.
Because moving (motion) video requires more data for more pixels, videos with higher resolutions generally require higher bit rates to improve video quality . In most cases, if the video quality requirements are not high (you will not choose 2K, 4K, 8K and other widescreen resolutions, ordinary 1080P is enough) rather than the fast transmission of files, it is best to choose a lower video resolution rate and let the video file transfer without stuttering, rather than using a higher video resolution to force viewers to sit and wait for all the data to transfer to their devices.
HD high and low bit rate video comparison
Now, it's important to understand that resolution is not the same as bitrate, resolution is the pixel size of your video. So if you have something that is 1920 by 1080, that's the resolution of the video, your video at 1920x1080 in HD can have a different bitrate.
So, if we take the example of two HD videos 1920 x 1080, one side is low bitrate, which means lower quality and higher compression, and the other side is high bitrate, which means higher quality and larger file size, But with higher quality, more data is encoded per second for video playback, and not all HD cameras shoot at the same bitrate.
That's why a GoPro might look different than an iPhone video, which might look different than a DSLR, which might look different than a movie camera.
They both shoot in 1920×1080 HD, but at different bitrates, which means they output different amounts of data per second while filming. There are a few other factors that go into why these different cameras look different in different ways like sensor size etc, but bitrate is a huge factor when you're watching a 1080P on YouTube at 24fps (24 frames per second) Bitrates are calculated on an average of 8-12 megabits per second (Mbit/s) for videos with:
YouTube Video Recommended Upload Encoding Bitrate Settings
Recommended Audio Bitrates for Upload
| type | audio bitrate |
|---|---|
| Mono | 128kbps |
| two-channel stereo | 384kbps |
| 5.1 stereo | 512kbps |
When you start looking at 2k or higher framerate files, the bitrate can hit an average of 20Mbps. You can upload a high bitrate video to YouTube and it will adjust to each setting of the resolution you're playing at, so if you're playing at 360P on a really slow internet connection it will play the low bitrate for you Rate version of the video, providing approximately 0.7 Mbit/s. YouTube will do all the encoding for you, but you usually want to upload your highest bitrate file to YouTube. They then encode the various sizes.
When you're watching HD, video is typically encoded between 4 and 8 megabits per second
When you're watching Blu-ray, generally, it's encoded somewhere between 24 and 40 megabits per second,
So a lot so those blu-rays are higher quality again, you can see some higher bitrate files online. Of course, streaming media Hulu and Netflix are developing towards high-quality media transmission, and we must see higher bit rate videos soon. With the development of the Internet we can upload higher bit rate content and play it at a faster speed.
Variable Bitrate and Constant Bitrate
It's important to note that when you're encoding a file, the difference between variable bitrate and constant bitrate is when you're exporting your video to the device, you can choose the settings you want, so the difference is
if we are exporting a video at a constant bitrate of 10 megabits per second, then the entire video will be at 10 megabits per second no matter what frame is being played.
Is there a more efficient form that is variable bit rate if we say we have a variable bit rate average 10 megabits per second up to 12 megabits and when the video is encoding and outputting it will be based on The content on the screen adjusts the bitrate.
So, if you have a large chunk of your video that's a black screen, or if there's no movement happening, it uses less data to encode those frames of video, which means you have a more efficient file size, with less compression, Because the entire video doesn't use the full 10 megabits per second.
I know this is a quick look at bitrates, but I wanted to give you the basic idea that the higher the bitrate, the higher the quality of your video, but also the larger the file size, which is why some can record really high Bit rate cameras need different forms of SD card or C fast card to record video, let's say you shoot a 4K and record it with a codec called Motion JPEG which is a very high quality codec , uses very high bitrates to capture, so you need a C Fast card to record,
These cards are expensive, and your camera has very durable standard SD cards. It is impossible for a standard SD card to collect so much data at one time.
So that's why to understand, if you want higher quality, bigger bitrate, you need bigger recording device, bigger file size, you need to be prepared, if you're going to upload it to YouTube Upload or throw it on Dropbox, the upload speed will be much slower.
So again to recap, the higher the bitrate, the better the quality, but the larger the file size, the lower the bitrate, the higher the compression, you get a file that is easier to transfer in the store, but you lose a little bit of quality,
So I hope this gives you a very basic understanding of bitrate, I don't want to get too deep, but I want you to grasp the meaning behind bitrate so that you know what it really is.
Optimal Bitrates for DVD Encoding
When it comes to choosing the best bitrate for DVD encoding, it's important to consider what device your video will be played on. We all know that the bitrates of web videos, mobile videos, and high-definition Blu-ray videos for TVs are different. Bitrates for high-definition Blu-ray video are typically in the 20Mbps range, standard-definition DVDs are typically 6Mbps, high-quality web video typically runs around 2Mbps, and mobile phone video is typically measured in kilobits (kbps).
We can take MPEG bitrate as an example. Each resolution has an approximate maximum bitrate while allocating enough bits per pixel. MPEG supports far more than double-digit bitrates, and it likely won't use it, and the result is just a bloated file.
352x240/288 = 2.0MB/s or 2000k max
352x480/576 = 4.0 MB/s or 4000k max
720x480/576 = 8.0 MB/s or 8000kbps max
(same variation for 704x480/576)
what is video resolution
What is video resolution?
Resolution is defined as the number of pixels organized or arranged by width and height on a screen or image
Video resolution is a measure of the number of pixels that make up a video frame.
Resolution is a parameter used to measure the amount of data in an image. It is usually expressed as ppi (Pixel per inch). The
320X180 of video refers to its effective pixels in horizontal and vertical directions. The ppi value is higher when the window is small. It looks like Clear; when the window is enlarged, because there are not so many effective pixels to fill the window, the ppi value of the effective pixels decreases, and it becomes blurred.
(When zooming in, the distance between effective pixels increases, and the graphics card will fill these gaps, that is, interpolation. The pixels used for interpolation are "false pixels" that are "guessed" based on the effective pixels up, down, left, and right, and there is no original video information)
Customarily, the resolution we refer to refers to the height/width pixel value of the image, and the resolution in the strict sense refers to the effective pixel value ppi within a unit length. The difference is here. The height/width pixel value of an image is indeed irrelevant to the size, but the effective pixel value ppi within a unit length is related to the size. Obviously, the larger the size, the smaller the ppi.
Video resolution is another indication of the overall quality of a video file, but it has nothing to do with the speed at which video data is transferred over the Internet .
In contrast, video resolution refers to the number of pixels that form a video frame, creating a video image on the screen. The more pixels a video contains, the higher the quality of the video.
pixel
Is the smallest unit of a graphic or image that can be represented or displayed on any digital device. Each little pixel is like a puzzle piece - when put together, you get a resolution - and when you get the resolution, you see an image. It's that simple!
Resolution = pixel width x pixel height
A high pixel count indicates better resolution, while a low pixel count indicates low-resolution video.
Resolution helps determine the quality of the video and how clear or lifelike it is. Generally, higher resolution means sharper video. It is measured by the number of pixels in the standard 16:9 aspect ratio, which is common in computer monitors and televisions.
For common resolutions like 1080 and 720, the naming convention is based on the number of pixels displayed on a vertical line on the screen. For 8K, 4K, and 2K video, the naming convention is based on the number of pixels running horizontally across the frame.
Because moving (motion) video requires more data for more pixels, videos with higher resolutions generally require higher bit rates to improve video quality. In most cases, if the video quality requirements are not high (you will not choose 2K, 4K, 8K and other widescreen resolutions, ordinary 1080P is enough) rather than the fast transmission of files, it is best to choose a lower video resolution rate and let the video file transfer without stuttering, rather than using a higher video resolution to force viewers to sit and wait for all the data to transfer to their devices.