The video format conversion bit rate
If the original video bitrate is 2Mbps, then I set the output bitrate to 2Mbps, will the quality of the video be reduced?
Image quality, i.e. clarity, is a combination of several factors, in addition to bit rate and resolution, including frame rate.
Video formats basic knowledge quote: We tell you about MKV, MP4, H.265, bitrate, color depth, etc. – 4K Knowledge Encyclopedia – 4K China Forum – 4K123!
This tutorial is meant to cover some basic video and audio concepts and terminology. You can answer the following frequently asked questions in more detail:
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What is the difference between these MP4/MKV formats? Which image is better?
How is the video bitrate calculated? Why is it the same 1080p video, some big and some small?
In what format is the image information stored in the video? Is it the same red, green and blue as the monitor?
What exactly does 8bit/10bit mean? Why is it necessary to watch 10-bit video on an 8-bit monitor?
yuv420/444 What do these signs mean? Which is better?
What exactly do lines, planes, textures mean? Why does the video have high and low frequency?
The higher the bitrate, the better the video quality?
This tutorial will be described in detail in the following modules:
1. Encapsulation format (MP4/MKV…) vs media format (H.264/FLAC/AAC…)
2. Basic video parameters: resolution, frame rate and bit rate
3 Image rendering method: RGB model vs YUV model
4, color depth
5, medium chroma sampling
6, low frequency and high frequency in space: plane, texture and line
7, low frequency and high frequency over time: dynamic
8, clarity and brief description
image quality 1. Packet format (MP4/MKV…) vs. media format (H.264/FLAC/AAC…)
MP4+MKV is the most common type of video files you download. These files are actually similar to a package and their suffix is the packaging method of the package. These packages contain video (image only), audio (sound only), subtitles, etc. When the player is playing, it first unpacks the package (the professional term is called split/split), outputs the video, audio, etc., and then plays it.
Since they’re just one package, that means the suffix doesn’t guarantee what’s inside or how much. Each element of the package, we call it a track, generally has the following:
Video (Video): In general, there should be, but there are exceptions, such as external audio track in mka format, in fact, there is no mkv video. Please note that when we talk about video, we do not include sound.
Audio (audio): Generally speaking, there should be, but in some cases it is muted, so there is no need to bring it.
Chapter: The segment information that came with the original Blu-ray Disc. If the file is checked out, you can see the effect with the chapters in the player:
.potplayer right click screen, option-play-show marker/chapter marker in progress bar.mpc -hc
right click screen, option-setting-on Progress bar shows chapter mark subtitles
(Subtitles): Sometimes the file comes with subtitles, and the subtitles are not directly embedded in the hard subtitles of the video, so they are packed together in the packing container.
Others may have attachments etc which are not listed one by one. There is not necessarily a single track for each type, as MKVs with multiple audio tracks are often seen.
Each track has its own format. For example, it is often said that the video is H.264, the audio is AAC, these are the formats of each track.
Common video formats are H.264 (can be subdivided into 8bit/10bit), H.265 (currently also subdivided into 8bit/10bit), RealVideo (common in early rm/rmvb), VC- 1 (Microsoft-led, common in wmv ). Basically H.264=AVC=AVC1, H.265=HEVC.
There are four common audio formats: FLAC/ALAC/TrueHD/DTS-HD MA, which are lossless, and AAC/MP3/AC3/DTS (Core), which are four lossy.
1. MKV supports encapsulation of FLAC as audio, while MP4 does not. But MP4 can also encapsulate lossless audio tracks (like ALAC, although it is generally believed that the efficiency of ALAC is not as good as FLAC)
2. MKV supports encapsulation of subtitles in ASS/SSA format,
