4K는 어떤 코덱을 써야 하는가?

http://www.4kshooters.net/2014/09/06/which-codec-is-most-suitable-for-your-4k-workflow/

 

 

 

"어떤 코덱이4K 워크 플로우에 가장 적합할까?"

이 질문에 대답하기 전에 우리는 비디오 코덱의 정의와 구조에 더 깊이 살펴 봐야한다.
코덱이 작동하는 방법에 대한 혼란과 오해가 많이있다.

그들 사이의 차이점은 하나는 특정 상황에서 등을 사용해야하는 코덱, 다른 것보다 더 나은하는 무엇인가

많은 영화 제작자 오히려 혼동 될 수있는 모든 지루하고 복잡한 기술 정보에서 떨어져 우리를 유지하면서 다음 깊이 비디오 자습서에서 데이비드 홍콩 코덱의 모든 중요한 측면을 다룹니다. 당신은 단순히 비디오를 촬영 즐길 당신이 코덱과 방법을 실제로 작동에 대한 자세한 내용을 알고 호기심이 경우, 다음 비디오는 당신을 위해 도움이 될 수 있습니다.

다음은 다윗이 그의 비디오에 포함 주요 내용은 다음과 같습니다 :

◾Different types of codecs – And why he frequently uses 4 different codecs on a single project.
◾Bit Depth – What it means and why it matters.
◾Chroma Subsampling – 4:4:4, 4:2:2, and 4:2:0, and when it becomes an issue.
◾Spatial Compression and Blocking – One of the most common artefacts you see with normal work.
◾Temporal Compression – Long-GOP codecs, inter-frame compression, and ALL-I codecs.
◾Lossless vs. Lossy compression – How image compression differs from data compression.
◾Bit Rate – How to calculate bit rates and the differences between kbps/kBps/Mbps/MBps.
◾Raw – Briefly, the difference between Raw, compressed, and uncompressed

 

 

 

 

 

 

As David Kong explains, there are certain situations where different codecs should be used. It depends whether you pick one as your primarily capturing codec or whether you use it for editing, delivering or on archival purposes. Whatever type of codec you use, in the first place, you should be aware of its technical characteristics and features such as bit depth, chroma sampling, bit rate, supported resolutions etc.
 
 There is a certain reason why many camera manufacturers have implemented the industry standard, robust and efficient intermediate codecs such as ProRes, DNxHD and Cineform in their products. The benefit of an intermediate codec is that it retains higher quality than end-user codecs while still requiring much less expensive disk systems compared to uncompressed video.

 

 

 

ProRes for instance, is a lossy video compression format developed by Apple for use in post-production that supports SD, HD, 2K, 4K, and 5K resolutions. It has different flavours such:

◾ProRes Proxy,
◾ProRes LT,
◾ProRes 422,
◾ProRes 4444
◾ProRes XQ.

 

On the other hand, DNxHD is another option intended to be usable as both an intermediate format suitable for use while editing and as a presentation format. DNxHD offers a choice of three user-selectable bit rates:

◾220 Mbit/s with a bit depth of 10 or 8 bits,
◾145 Mbit/s bit depth 8 bits
◾36 Mbit/s with a bit depth of 8 bits.
◾DNxHD data is typically stored in an MXF container, although it can also be stored in a QuickTime container.
◾Unfortunately, DNxHD still doesn’t support resolutions higher than 1080p.

 

The CineForm is an intermediate codec that is most commonly wrapped within AVI or MOV container. Current implementations support image formatting for 10-bit 4:2:2 YUV, 12-bit 4:4:4 RGB and RGBA, and 12-bit CFA Bayer filter RAW compression. Compression data-rates typically range from 10:1 to 3.5:1, based on quality settings. There is also an uncompressed mode for RAW files. Cineform supports resolutions up to 4K as well.

 

It is save to say that any of the above options could be used in almost any situation as a universal codec for capturing, editing, delivering and archival all-in-one.  However, in situations where you shoot in resolutions above HD, as a rule-of-thumb, it is always better to choose ProRes or Cineform as an intermediate codec for your end-to-end workflow depending on operating system you use (Mac or PC).