Must-learn video coding knowledge for film and television production

Video coding knowledge is a must for film and television production

In terms of coding, we have always had a lot of doubts and misunderstandings, such as how they work, what are the differences between codings, and which coding is better , which encoding should be used in specific situations, etc. Professor David Kong’s video will cover all important information about encoding, making you feel that encoding is no longer boring and complicated. To be honest, this is the most comprehensive we have seen in these years. The most understandable explanation of all aspects of coding! If you like or work in film and television, and want to know how coding works and more information, then you must watch the following video:

< /p>

The following are the topics covered in the video:

1. What is encoding? How is it different from a container?

2. Different types of encoding? David Reasons for always using 4 different encodings in the same project

3. Bit depth? What is bit depth and why is it important? 4. Chroma sampling? 4: 4:4,4:2:2,4:2:0

?

5. Space compression and blocking

6. Time compression? Long GOP Coding, interframe compression and all I coding

7. Lossless compression vs. distortion compression? The difference between image compression and data compression

8. Bit rate? Bit rate The difference between calculation and kbps/kBps/Mbps/MBps

9. Raw? The difference between original material, compressed material and uncompressed material

David explained that different codecs It is used in different situations, depending on whether you choose an encoding as your primary capture encoding or whether you use it for editing, delivery, or archiving work.

No matter what type of encoding you use, first What you should be aware of is its technical characteristics and capabilities, including bit depth, chroma sampling, bit rate, and supported resolutions.

Camera manufacturers specify industry production standards and efficient performance in cameras. Intermediate codecs ProRes, DNxHD and Cineform are used for a reason. The advantage of an intermediate codec is that it is higher quality than end-user codecs and requires a cheaper disk system than uncompressed video.

For example, ProRes, This is a lossy video compression format. It is the encoding used by Apple in post-production. The supported resolutions are SD, HD, 2K, 4K and 5K.

ProRes has several different versions:

　1. ProRes Proxy

　2. ProRes LT

　3. ProRes 422

　4. ProRes 4444

　5 , ProRes Choice:

1. The code rate is 220 Mbit/s, the bit depth is 10 or 8 bits

2. The code rate is 145 Mbit/s, the bit depth is 8 bits

p>

3. The bit rate is 36 Mbit/s and the bit depth is 8 bits

4. DNxHD data is stored in MXF memory and can also be stored in QuickTime

5. However, DNxHD only supports resolutions below 1080p

CineForm, an intermediate code, is usually included in AVI or MOV memory. Currently, it supports formats such as 10-bit 4:2:2 YUV and 12-bit. 4:4:4 RGB and RGBA and 12-bit CFA Bayer raw data.

Based on quality settings, compressed data rates range from 10:1 to 3.5:1. Raw files are also available in uncompressed mode, Cineform The maximum resolution that can be supported is 4K.

If the video resolution you shoot is higher than HD, it is best to choose ProRes or Cineform as the intermediate encoding. Which encoding among the two should be chosen? , it depends on whether your operating system is Mac or PC. ;