Data Rate For 2k & 4k

[azadfilm-jami]

Hi all, i was totally confused how can we get 4k footage squeezed on a flash card fast enough unless its compressed 0highly compressed. am i right? please dont think im trying to ditch RED. im a buyer myself but how compressed is the footage for it to get on to a hard drive or CF card. cuz yesterday my Mac Pro with Xraid with fiber channel with HD-SDI couldnt get into the system uncompressed cuz the Data was too heavy even with 3.2 tera fiber channel. and the data rate was above 150 MB/s but i heard RED is 35 Mb/s. but thats very low rate no?

please need help im confussed. im getting the camera next month just want to know what im getting thats all. i love RED please dont get me wrong. its pure help needed

 

[Brigham Edgar]

threads

threads

A little searching about this on RED's website and through the forum will give you the answers.

If you are buying a RED i would have thought you should already be up to speed on this.:umm:

 

[hunterrichards]

Its 36M (big B)/s

Recording 4k is one thing but recording 4K on a CF card at a usable data rate is what seals the deal...

 

[Stuart English]

Image Quality

Image Quality

Hi all, i was totally confused how can we get 4k footage squeezed on a flash card fast enough unless its compressed 0highly compressed. am i right? please dont think im trying to ditch RED. im a buyer myself but how compressed is the footage for it to get on to a hard drive or CF card. cuz yesterday my Mac Pro with Xraid with fiber channel with HD-SDI couldnt get into the system uncompressed cuz the Data was too heavy even with 3.2 tera fiber channel. and the data rate was above 150 MB/s but i heard RED is 35 Mb/s. but thats very low rate no?

please need help im confussed. im getting the camera next month just want to know what im getting thats all. i love RED please dont get me wrong. its pure help needed

Yes, the data is compressed, about 28 - 36MB/s in the case of 4K data. So the trick the RED engineering team have pulled off is how to maintain image quality at that compression rate. The proof that this task has been successful is in the quality of the images that many, many customers have produced. So rather than explain how we did that (its a long technical discussion) I'd ask you you accept that as the evidence.

 

[Steve Freebairn]

It uses a very efficient compression scheme which allows for very high quality at a very small (considering 4k) data rate, which is anywhere from 2.24 to 2.88 times DVCProHD (100 Mbits/sec).

 

[David Newman]

It uses a very efficient compression scheme which allows for very high quality at a very small (considering 4k) data rate, which is anywhere from 2.24 to 2.88 times DVCProHD (100 Mbits/sec).

Efficient yes, but not to the numbers you use.

DVCProHD (960x720x8bit Luma + (480x720x8-bit Chroma)*2) * 60fps = 663Mbit/s uncompressed (6.63 : 1 compressed.)
REDCODE36 (4096x2304x12-bit RAW) * 24fps = 2718Mbit/s uncompressed (9.43 : 1 compressed).

Only 1.42 difference between the two regarding compression ratio alone.

Factors favoring REDCODE, Wavelet beats DCT, and bigger imaging are easier to compress (a human visual factors thing.)

 

[Lars Xang]

How does it compare to AVCHD?