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I have a Blackmagic Intensity Pro 4K video capture card and Panasonic GH4, which can output 10-bit 4K from the HDMI port.

I'm running Windows 10 and I have two 1 TB SSDs, but with write speeds of about 450 MB/s, they are not fast enough to capture uncompressed 10-bit video, which is the only 10-bit option the included Blackmagic software provides.

I'm trying to find video capture software, but Google only reveals abandoned software like Virtualdub and tools for doing screencasts.

Is there video capture software that can handle 4K/10-bit encoded with some kind of codec on a "normal" SSD?

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    ffmpeg with the decklink API enabled. You can get such a precompiled Windows binary from ffmpeg.zeranoe.com/builds – Gyan Jan 26 '17 at 18:20
  • Hmm, I have ffmpeg installed for conversion, but didn't know it could do capture. I have the binary from that page installed, but when I run ffmpeg -f decklink -list_devices 1 -i dummy from the examples in the documentation (ffmpeg.org/ffmpeg-devices.html#decklink), I get the error "Unknown input format: decklink" – Patrick Kenny Jan 26 '17 at 18:33
  • Check the banner of your ffmpeg for --enable-decklink. – Gyan Jan 26 '17 at 18:44
  • Yep, it's there. ffmpeg version N-83133-ge664730 Copyright (c) 2000-2017 the FFmpeg developers built with gcc 5.4.0 (GCC) configuration: --enable-gpl ... --enable-lzma --enable-decklink --enable-zlib – Patrick Kenny Jan 26 '17 at 18:49
  • Broken since Dec 10. Get an earlier build from ffmpeg.zeranoe.com/builds/win64/static – Gyan Jan 26 '17 at 19:26
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Uncompressed Prores HQ at 10 bit will yield extremely large file sizes. Is there a reason you want prores? 4K 444 10bit uncompressed would be, in my opinion, better captured as an uncompressed AVI "true uncompressed". Or, if your decklink allows it; Uncompressed MOV using the animation codec with Alpha turned off, only RGB.

Also; you may want to use 2 SSDs and RAID 0 them; while your single SSD may be able to sustain 450mb/s, it is going to fill up rather quickly, and any hiccups will cause a stop in capture or drop in frames.

For a fast HDD solution, I recommend an Intel 4 Channel SAS Raid Card; with 4 SSDs in RAID 0; which of course you would want to back up after capture (due to no fault loss protection using RAID 0. I use this solution using (2) Intel Cards running (4) 1GB Crucial SSDs and I get sustained 2.4 GB/S read and write. So once your capture is finished, you can transfer all your files from your first RAID 0 to your 2nd RAID 0; in roughly 25 minutes - provided you filled the full 4 TB.

There is also a RAID SAS expansion card which allows more drives which can be helpful if you plan on running a RAID 5, 6 or 1, or other setup.

As far as software is concerned; FCP would interface with the Intensity Pro; as would Premiere Pro (recommended) I also believe that Blackmagic has a free download package that allows for captures in various (non-prores) codecs. But uncompressed would be available.

I'd only close with I see no reason to tie yourself to prores unless the post house you're working with or client demands it. AVI or MOV as animation when dealing with 444 is by far the way to go.

  • Thanks, yes I wanted just 10-bit uncompressed, not prores; I'm on Windows anyway so dealing with prores is a pain. The Blackmagic software has an option for 10-bit uncompressed but it chokes on my system, even though the Blackmagic speed test software says it should be fast enough. I also tried the two drives I have in a RAID 0, but that didn't work with the Blackmagic software. Maybe I'll give Premiere a try; I've been using Resolve, but it doesn't have that option. – Patrick Kenny Apr 8 '17 at 22:22
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    Avoid prores then; there is literally no need for it. I'm sure this comment would take heat for saying this; but cutting on apple and the FCP platform is a dying trend. The power now is in custom PC's running Intel XEON chips; in rack chassis setup. You have full control of how you want to set up- AND expand your system. Adding ram; graphics cards; upgrading, it's far more flexible. I would however; recommend at the very least using 2 SSDs; and Raiding them as a RAID 0. Your motherboard should have 4 ports marked RAID (likely white SATA ports). Use Rapid Storage Controller DL from Intel – McFlySoHigh Apr 8 '17 at 22:27
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I managed to get this working with ffmpeg using prores of the lowest quality (LT). This does not answer the original question exactly-- I still am trying to find a way to do uncompressed 10-bit, or least high quality prores-- but for now, this is the best I've been able to get.

ffmpeg -bm_v210 1 -rtbufsize 1500M -threads 4 -f decklink -i "Intensity Pro 4K@20" -c:a copy -c:v prores -profile:v 1 MYFILE.mov

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