4K RF Setting Help

[zack28]

Hi

I have shot nearly a third of my Holiday Videos in 4K mode when i first got my Note 3 smartphone.
Whats the RF range for 4K video (2160p) I cant seem to find a value anywhere

I don't have HB Activity Log yet as i don't know what value to use

Here some info on one of the gargantuan clips
.

Code: Select all

General
Complete name                            : C:\Users\ZackD\Desktop\Note 3\20150415_152723.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom
File size                                : 1.45 GiB
Duration                                 : 4mn 18s
Overall bit rate                         : 48.0 Mbps
Encoded date                             : UTC 2015-04-15 10:01:43
Tagged date                              : UTC 2015-04-15 10:01:43

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L5.1
Format settings, CABAC                   : No
Format settings, ReFrames                : 1 frame
Format settings, GOP                     : M=1, N=30
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 4mn 18s
Bit rate                                 : 48.0 Mbps
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Variable
Frame rate                               : 30.000 fps
Minimum frame rate                       : 28.745 fps
Maximum frame rate                       : 31.414 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.193
Stream size                              : 1.44 GiB (100%)
Title                                    : VideoHandle
Language                                 : English
Encoded date                             : UTC 2015-04-15 10:01:43
Tagged date                              : UTC 2015-04-15 10:01:43
mdhd_Duration                            : 258348

Audio
ID                                       : 2
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 40
Duration                                 : 4mn 18s
Source duration                          : 4mn 18s
Source_Duration_FirstFrame               : 60ms
Bit rate mode                            : Constant
Bit rate                                 : 128 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Compression mode                         : Lossy
Stream size                              : 3.85 MiB (0%)
Source stream size                       : 3.85 MiB (0%)
Title                                    : SoundHandle
Language                                 : English
Encoded date                             : UTC 2015-04-15 10:01:43
Tagged date                              : UTC 2015-04-15 10:01:43
mdhd_Duration                            : 258752

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The Ranges for (x264)

SD was 18-20 (i used 20)

720P/1080P was 20-23 (I used 22)


I'm assuming then the Range for


2160p is 23-26

Just need a guideline

Thanks

Zack
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[rollin_eng]

Sounds about right, your best bet is to try a few encodes and see what is good for you.

[Deleted User 13735]

Just see what looks good without artifacting in high motion objects.

[nhyone]

If you intend to replace your original video with the encoded one as your new "master" due to space constraint, I would err on the side of caution and use the veryslow preset and CRF 20 at least, and hope the video requires less -- much less -- than 48 Mbps.

If I have to use a high CRF to save space, I would consider reducing the resolution to 1080p.

[zack28]

I would consider reducing the resolution to 1080p.

.

Hi

I did consider for a while to downscale to 1080p
but in about 3-4 years time, most households will have 4k resolution TVs/Players/Computer/Mobile Phone/Tablets.

Would regret to have down-scaled to 1080p and lost the quality

Even Though I shot these clips at 4K by mistake when i got my Note 3....Have to say Wow ... 4K looks amazing

.
Thanks again for all your input

Zack
.

[nhyone]

Well, that's between 4K at CRF 24 and 1080p at CRF 20, say. I'll try both and see which looks better. 4K at higher CRF may be worse quality than 1080p upscaled.

Of the devices you mentioned, the only one that could look worse is a large screen TV (maybe >50"). The others are fine at 1080p, due to our eyes' limited resolving power and typical viewing distances. On my 5.5" QHD screen (1440 x 2560), 360p videos look indistinguishable from 1080p ones -- or perhaps I don't have very good eyesight?

Update: one more thing. Downscaling from 4K to 1080p creates your own "4K-remastered FHD", which will be sharper than regular 1080p, provided the camera can resolve >1080p details. (It should.)

[BradleyS]

Generally speaking, more resolution is almost always better, even at lower quality. Personally, there are times where I'd rather have a higher quality video at a lower resolution. Depends on a lot of factors.

Anyway, 1.45 GiB isn't all that huge in the grand scheme of things. Storage is relatively inexpensive these days. Keep the originals!

[Devore]

How good is the 4k quality on a smartphone camera? It's a short enough clip, you can do some test encodes to see what looks good. Assuming the camera is not that great (although you seem impressed with it) downscaling to 1080p with slightly higher CRF and preset might be plenty good enough even if the display upscales it back to 4k. When it comes to fine detail resolution, I haven't really been impressed with any consumer- or smartphone-level camera, for moving or still pictures, thus ultra-high resolution is wasted and captures noise anyways.

Aside from a general CRF guideline, if you want good results you'll have to tailor them to the individual input file and viewing scenario.