Video Basics Part 2
There are two types of bit rates
Bit rate type
There are two types of bit rates.
Constant Bit Rate (CBR)
Variable Bit Rate (VBR)
Constant Bitrate keeps the set bitrate constant regardless of the video content.
An important feature is that the load on the playback device (PC or smartphone) is small, but since the pattern with violent movement becomes a block, it is necessary to set a relatively large bit rate.
In other words, the file size tends to be large.
On the other hand, variable bit rate is a method that automatically increases the bit rate for parts with complicated movements and reduces it for parts with little change, so the overall file size can be kept small.
Instead, the load on the playback device (PC or smartphone) will be high, so the movement may be choppy depending on the device.
Bit rate type Features
Constant Bit Rate (CBR) The
File size tends to be large, making it less burdensome for the playback device.
Variable Bit Rate (VBR)
The file size, which is a large burden on the playback equipment, can be kept small
Which is better depends on the application, but if the image quality is fixed, like Youtube, we recommend variable bit rate with high image quality and light file size.
He didn’t know the difference between the two when he was working. Let’s keep it in our head as knowledge.
Video Basics: What is Frame Rate?
Frame rate knowledge is essential for those who are just starting to record and edit videos!
The video appears to move “showing continuous still images one after another.” Right now, “frame rate (fps)” is the number of still images displayed per second.
It is easy to understand if you imagine a flip book.
Photos and videos feel different, but videos are a collection of photos.
The frame rate is expressed in the unit of “fps”.
This is an abbreviation for “Frame Per Second” and is the number of still images displayed per second.
Remember the general frame rate
Generally, movies are recorded at 24 fps and TV shows are recorded at 29.97 fps.
29.97fps is often downgraded to 30fps because the numbers are not sharp.
The camcorder was originally designed to record video for viewing on a television, so by default it records at the same 30fps as a television.
You can see that a movie has 24 photos per second / a TV has about 30 photos per second.
Frame rate (fps) Features
15 fps Single segment stream frame rate
30 (29.97) fps Domestic TV broadcasts and video cameras in general.
24 fps Frame rate used in movies
60 fps In recent video cameras, as a project with a definition higher than 30 fps, the number of cameras that can record and play back at 60 fps per second is increasing.
The higher the frame rate, the smoother the video will be, but it won’t be blurry and the video won’t be natural.
When exporting as video, there is no question that it should be set to 30 fps or 24 fps general.
Please note that if you edit a video recorded at 24fps to 30fps, you will end up with choppy video due to a lack of still images.
When recording a video → edit, be sure to check the camcorder’s settings (frame rate).
resume
that’s it! As a basic knowledge of video, I explained the difference between “bit rate” and “frame rate”.
The names are similar, but they are completely different.
By the way, what can you think about when video motion stutters
The bit rate is too high to keep up with the playback device’s processing.
The frame rate setting is too low
These two are possible.
There is no doubt that the bit rate and frame rate should be basically set according to the presets.
However, it is easy to fix it if you know the cause, such as when there is a problem playing the video.
