I've been searching for an answer to this but haven't been able to find anything definitive.

I use an Orah 4i 360 livestream video camera. It sends the camera video to a stitching box. The stitching box sends out 4K (4096x2160) H.264 prestitched 360 video over RTMP. It also can record to internal SD card. But it can't record internally at the same time it is outputting over RTMP.

In order to record the livestream, you have to use the HDMI 2.0 output, which also sends the the same H.264 mp4 video, but without the RTMP 360 control data.

I need to record the 4K mp4 video from HDMI to an external HD or SD card. Since it is already encoded mp4, even though 4K, it doesn't really need the data record rate that something like an Atomos Ninja Inferno or Black Magic options. They record RAW uncompressed video, and you pay for that. I only need to record mp4, even though 4K from HDMI.

So, does anyone know of a cheaper solution than Atomos has to record 4K HDMI mp4 to an external HD or SD card?

  • 1
    If it is outputting over HDMI, then it is not compressed H.264. HDMI 2.1 only uses DSC for resolutions over 8K. – Michael Liebman Jun 10 '17 at 16:04
  • You're kind of doing things backwards. Send feed to recorder, then loop and send feed to stream. I would do this with a computer and capture card (can take hdmi in), then something like vmix or wirecast to send to Web. – user24601 Jun 10 '17 at 21:13

Would you consider using a computer equipped with a 4K HDMI capture card like BlackMagic Intensity Pro 4K, to write to that SD card?

This will be cheaper than buying a recorder and you will have full control over how you capture this 4K stream over HDMI.

| improve this answer | |
  • Yep. This is what I do. Capture first, then stream – user24601 Jun 10 '17 at 21:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.