Editing 4:2:2 without conversion?

[Al Slamecka]

I recently shot a bunch of vacation video at UHD 150Mbps 4:2:2 on my LS-300.

Similar to past experience shooting HD at 4:2:2: on the JVC, I'm unable to play back the native 4:2:2 video on my iMac (i.e. Quicktime) or within Davinci Resolve so I convert to Prores HD using Brosoft Video Converter. Is there any trick to getting the files to play natively without conversion on OSX Sierra?

One other observation... I have two SanDisk 256GB cards in Slots A and B configured to record video in series. Both show the capability to recording about 225 mins of UHD 150Mbps 4:2:2 when empty. I filled up card A on the trip and just a few mins on card B. When moving the footage from card A to my iMac, the total footage only amounted to 108GB... nowhere near the capacity of the 256GB card.

I popped the card back into the JVC and confirmed that it showed 0 mins left for recording on card A. All the footage I shot on card A is there but I haven't had a chance to total up the minutes to see if it's near the 225 min capacity. Will investigate a bit more but just wanted to share my observation.

Any thoughts on either comments above are appreciated :)

[William Hohauser]

First of all which editing program are you using on your iMac? How old is this iMac? The video card in it may not be able to handle decompressing AVCHD 4:2:2 in realtime, especially at 150Mbps.

As I am not sure how the JVC compressor is making 150Mbps at 4:2:2 it's hard to explain the discrepancy between the footage count and the results. I know that the standard setting in 4:2:0 have a per frame set bandwidth so if the chip says 115 minutes when empty you can be reasonably assured that's what a full chip gets. Try recording a still life or something with little motion happening on a different chip and see what happens.

It might be that there is a calculation error in the firmware JVC sent.

[Al Slamecka]

Hi William -

I'm using Davinci Resolve (both v12.5 and v14 Beta) to edit and grade the footage. I have no problem editing any JVC 4:2:0 UHD footage or the converted 4:2:2 UHD Prores footage on my early-2015 iMac with 4GHz Intel i7 processor and 32GB RAM. The video card is an AMD Radeon R9 with 2GB of memory.

I have a hunch the issue is related to JVC file format as typically any file I can edit in Resolve can also be played natively in Quicktime. That's not the case with JVC 4:2:2 footage but I find it interesting I can play / edit JVC 4:2:0 (HD and UHD) footage with no problem. Just hoping to find out if this is true for everyone or just me :)

I will run the still life test to measure if there's a discrepancy between the estimate of recorded time the camera calculates vs. the actual recorded time. Thanks for the suggestion.

[William Hohauser]

How are you ingesting the footage to Resolve? Direct transfer from the camera SD card to your hard drive and then into Resolve? Are your camera files native QuickTime or AVCHD?

[Christopher Young]

Originally Posted by William Hohauser

this iMac? The video card in it may not be able to handle decompressing AVCHD 4:2:2 in realtime, especially at 150Mbps.

Therein lies the problem if your system is running Nvidia hardware. What the situation is with AMD and Apple specifically I cannot comment because i haven't gone down those paths. The Windows journey has been enough so far!

Decoding 4:2:2 is not natively supported on Nvidia hardware in H.264. 4:2:2 is not included as part of the H.264 profile set. We first ran into this problem about three years back when we started to work with Sony's XAVC 4:2:2 10-bit codec, which is of course H.264 based. All of the camera manufactures implementations and 4:2:2 derivations of the H.264 family are outside of Nvidia's H.264 hardware capabilities. This is also one of the problems people have been running into with the 4:2:2 10-bit implementation of H.264 that Panasonic have been using in the GH5. For users of Adobe Premiere the decoding of 10-bit 4:2:2 runs even deeper. When we dug deeply into these 4:2:2 issues and contacted Nvidia this is what they pointed us to. A few statements from Nvidia. You will find a number of links further down which will reveal more info on this Nvidia Cuda decoding conundrum.

"NVIDIA GPUs contain a hardware-based decoder (referred to as NVDEC) which provides fully-accelerated hardware-based video decoding for several popular codecs. With complete decoding offloaded to NVDEC the graphics engine and the CPU are free for other operations. NVDEC supports much faster than real-time decoding which makes it suitable to be used for transcoding applications, in addition to video playback applications.

NVDECODE API enables software developers to configure this dedicated hardware video decoder. This dedicated accelerator supports hardware-accelerated decoding of the following video codecs on Windows and Linux platforms: MPEG-2, VC-1, H.264 (AVCHD), H.265 (HEVC), VP8, VP9 (see table below for codec support for each GPU generation)."

A further Nvidia statement that points out that there are further particular issues for users of Adobe products:

“NVIDIA Geforce graphics cards have offered 10-bit per color out to a full screen Direct X surface since the Geforce 200 series GPUs. Due to the way most applications use traditional Windows API functions to create the application UI and viewport display, this method is not used for professional applications such as Adobe Premiere Pro and Adobe Photoshop. These programs use OpenGL 10-bit per color buffers which require an NVIDIA Quadro GPU with DisplayPort connector. A small number of monitors support 10-bit per color with Quadro graphics cards over DVI."

Since we discovered these issues we have now switched two systems to Quadro cards, display port outputs and 10-bit monitors. The difference is noticeable in terms of 10-bit playback in spite of the fact that the 4:2:2 color is still not supported. The only way we are getting 100% 10-bit 4:2:2 color is by converting all 10-bit 4:2:2 H.264 based video to a quality 10-bit 4:2:2 NON H.264 based codec so the CUDA hardware is not utilized. On windows we are using Cineform. I guess for Apple users the codec of choice would most likely be ProRes.

A few URL pointers.

NVDEC - Hardware-Accelerated Video Decoding

https://developer.nvidia.com/nvidia-video-codec-sdk

Video Encode and Decode GPU Support Matrix

https://developer.nvidia.com/video-e...matrix#Decoder

10-bit per color support on NVIDIA Geforce GPUs (Adobe products Premiere etc)

10-bit per color support on NVIDIA Geforce GPUs | NVIDIA

How to enable 30-bit color on Windows platforms

How to enable 30-bit color on Windows platforms | NVIDIA

If you really require 10-bit 4:2:2 color depth in your H.264 renders you will need to use either hardware or software that supports these “optional” outside of the H.264 standard 4:2:0 CUDA render capabilities. Such as this Mainconcept software:

http://www.mainconcept.com/us/gettin.../products.html

or this Kyrion hardware or similar:

http://sportsvideo.org/main/files/20...M3101-2010.pdf

A further list of software encoders that will support H.264 4:2:2 flavours can be found here. Go right down the page to see easy to read tables:

https://en.wikipedia.org/wiki/H.264/MPEG-4_AVC

I hope some of this might throw a little light on the confusion surrounding these 10-bit 4:2:2 H.264 issues.

Having now understood these issues on our end our workflow is now a smooth seamless 10-bit 4:2:2 experience rather than the frustrating issue it first was with 4:2:2 H.264 based codecs.

Happy editing folks!

Chris Young
CYV Productions
Sydney

[Al Slamecka]

I copy the files from SD card to hard drive then import into Resolve. The JVC 4:2:2 recorded files are .MOV which is a Quicktime compatible encapsulation or wrapper of the raw video/audio by JVC. The .MOV files however are not recognized by as playable by Quicktime or Resolve after importing so my best guess is that something is sufficiently wrong with the encapsulation / not supported in playback hardware / not supported in QT to prevent playback.

I am able to open/play the JVC native 4:2:2 files in VLC and view the file properties. VLC reports the codec as "H264 - MPEG-4 AVC (part 10) (avc1)". An earlier version of VLC reported the decoded format as 'Planar 4:2:2 YUV' but this detail is not part of the stream info in the latest VLC version. Even so, this seems correct to me as it matches what the camera is supposed to record so I'm stumped. I attempted to 're-encapsulate' a JVC 4:2:2 file - not transcode - into QT compatible as VLC allows for this however the output is still not recognized and the effort similar to transcoding so no real benefit.

Would still like to know if anyone has had a different experience playing back JVC 4:2:2 recorded files in Quicktime on OSX in a recent model Mac.

Appreciate the helpful input.

[Nick Haman]

Just to note, I can't play the files natively in Quicktime either, but in Premiere, they play just fine without conversion, so I just watch everything there.

I wish you could record proxys to the second card in camera, that'd make thing a lot easier, but for some reason, that's not possible in any of the 4K modes. I assume due to processing power etc.

About the time on the cards thing. It might be that only cards up to 128gb are supported, so the camera's calculations are based on that? Once it fills up that allotted space, it simply switches slot and won't go any further. - honestly that's just a guess, but kind of makes sense to me. You could test this buy putting a 128gb card in and seeing if it still says 225 mins.

[Stein Onshus]

Editing on my 2015 MacBook pro works fine directly from import to FCPX, but Quicktime does not handle the 4k 422 150 file. Will try on my iMac later this week.

[Al Slamecka]

Thanks Guys.

I have FCPX on my iMac and confirmed 4:2:2 works without transcoding. So if Premiere works too, I wonder what about the file Davinci Resolve doesn't like.

When I import into Davinci, the video window says 'Media Offline' however it correctly reads the file attributes and it plays the file's audio. Changed a few video parameters in Project Settings but no luck.

I'm going to search for some info on the BMD Post Production forum and will post a question there too if I can't find an answer.

[Nick Haman]

Let us know what you find - could help others :)

[Zach Cobb]

The JVC 4:2:2 Codec does not work in DaVinci. Talking with Blackmagic, they have not had enough interest expressed to develop a decoder for it. The codec is proprietary and Blackmagic would have to work with JVC to incorporate it into their workflow.

[Lee Powell]

Originally Posted by Christopher Young

If you really require 10-bit 4:2:2 color depth in your H.264 renders you will need to use either hardware or software that supports these “optional” outside of the H.264 standard 4:2:0 CUDA render capabilities. Such as this Mainconcept software:

http://www.mainconcept.com/us/gettin.../products.html

Thanks for the detailed account of your experiences working with 10-bit 4:2:2 H.264 codecs on Windows. The MainConcept link you included above contains links to their SDK products, which are targeted for develpers building OEM products rather than end-users of post-production software. MainConcept also offers an Adobe Premiere Pro plug-in that supports fully-customizable encoding and decoding of 10-bit 4:2:2 H.264 files in both Premiere and Adobe Media Encoder: TotalCode for Premiere Pro. However, this plug-in is compatible only with stand-alone versions of Windows Adobe CS5, CS5.5, and CS6:

https://www.mainconcept.com/us/produ...de-cs-5-6.html

I've also had experiences using nVidia 10-bit Quadro video cards to enable 10-bit color depth support on Windows 7. While I was able to get this to work with an NEC PA272W monitor, it was finicky and difficult to confirm whether 10-bit color was fully activated. The problem is that Windows 7 does not provide a user-accessible manual color depth selection mechanism. You have to assemble a video driver and hardware chain that fully supports 10-bit color and rely on Windows to automatically detect this configuration and enable it. I found this highly problematic in practice, and reverted back to affordable nVidia 8-bit GeForce video cards.

[Christopher Young]

Yes understood. The MC reference was mainly to point out that there were solutions to the 10-bit 4:2:2 problem. The 4:2:2 depth specifically.

Regarding the 8-bit GeForce cards they will automatically open up the 10-bit option in Win 7 and so far we have had nil issues when using the latest Nvidia drivers. The video driver chain with the latest Nvidia drivers and a fully updated Win 7 box just works for us on the 1080 cards without any intervention.

There was a period where the 10-bit driver option was disabled on the Nvidia GeForce drivers. Without doing some fact checking I can't remember on which driver version the GeForce 10-bit option was re-enabled. As long as you have the correct drivers to enable that 10-bit option then we have found no problem using the the GeForce cards in 10-bit using the BenQ 270 monitors. Which by the way we find extremely good given the price range they sit in. I've used the Sony Trimaster OLED monitors in the recent past and they are very good bar the fact that if there was no timeline action they would quite quickly go into a sleep mode to save the OLED which I found rather annoying. I'd put these BenQ 270 panels right up there witth the Sony Trimasters for editing and grading with. The only thing being the BenQs dont have SDI. Not a big issue in the post area but nice to have on location.

BenQ PV270 Video Post-Production Monitor with 100% Rec.709 and 96% DCI-P3 color gamut support | BenQ Global

We have a couple of the GeForce 1080 cards with the current drivers in other work stations. When running them to the BenQ 270's via their Display Ports under the Nvidia Control Panel a new bit depth option appears. This is probably best explained by watching the video link below rather than me trying to explain it longhand. The BenQ 270 monitors then just drop straight in to the 10-bit mode once the 10-bit option is selected in the Nvidia Control Panel. As we produce for broadcast we then just select the Rec 709 mode on the BenQ displays and everything is running 10-bit under Win 7 with no issues. The 10-bit option on the GeForce cards will not activate unless a full 10-bit compliant path is detected.

Nvidia Geforce 10bit Setting - YouTube

Must admit I didn't know MC had a plugin version for Adobe. We don't use Premier so wasn't aware this option was available. With regards to TotalCode we run that as a standalone application as it handles all flavors of CBG and VBR XAVC beautifully which then allows us with TotalCodes' massive feature set to export to almost any format we wish. Love TotalCode, Not cheap but worth every cent for us.

Chris Young
CYV Productions
Sydney.

[Al Slamecka]

Zach -

Thanks for the info regarding your conversations with Blackmagic. From my initial scan of BMD's Davinci forums there aren't any references to JVC 422 decoding so it perhaps confirms there's low demand for producing a Davinci decoder.

On the whole, there's little love within the BMD forum community for 8-bit codecs (due to flexibility in color grading) so even less likely that BMD will develop a decoder. Seems like transcoding JVC 422 is the only way to go for Davinci Resolve... shame as we have J-Log1 and would be nice to work with it straight from the camera in Resolve.

Somewhat related... I've been pinging the Film Convert folks for a JVC J-Log1 profile for their software and they say they've seen little demand and haven't been able to source a camera to develop one. Wish JVC would step in to provide them a camera as there's even a profile now for the iPhone 7!

[Jakob Schlupmann]

To get Resolve to read JVC's 422 files the best way is to rewrap them into mxf.

The same problem arose with Sony/Magix Vegas and was discussed in following thread : https://www.vegascreativesoftware.in...5152/#ca650043

You will find some tools GJeffrey provided there to rewrap 422 movs into mxfs (with ffmepg) which is much faster than transcoding. The mxfs are then directly read by Vegas & Resolve. At least this did work for all 422 files from my JVC ls300.