If you haven’t been paying attention, live streaming has become a big business. Streamers are getting out of their basements and moving around among us. While IRL streams may not be our cup of tea, the technology behind creating a solid high upstream bandwidth wireless internet connection is. Sure you can stream with a phone, the top streamers want something a bit more reliable. Enter [Gunrun], who has designed a backpack just for mobile streaming.
The backpack starts with a Sony AS300 Camera. [Gunrun] likes this particular camera for its exceptional audio capabilities. Network connections are handled with no less than four LTE modems. You never know which carrier will have good service out in the field, so the modems are available from a variety of carriers.
The real problem is bonding connections between LTE modems from various carriers, setting up streaming accounts, and piping captured data from an HDMI capture over those accounts. The average hacker would go at it with an HDMI capture card and a Linux Laptop. Most streamers need a more plug and play solution though, so [Gunrun] uses a LiveU Solo HDMI video encoder for the task.
This isn’t a cheap solution, all those parts together along with a beefy battery, LTE data plans, and of course a backpack to hold it all makes for a package north of $2000. Even at this price, plenty of streamers have been following [Gunrun’s] instructions and building their own setup.
Hackers do a bit of live streaming too – check out how [cnlohr] reverse engineered the Vive, while valve engineers played along in the chat.
Looks like we have niche on market…
Not really. Nearly all the live shots you see on your local news are using bonded cellular. You can buy backpacks like that off the shelf.
You have to shell out 600 bucks a month to get a reliable connection… wow.
Looks like the most expensive part of the set up is the HDMI encoder. I still reckon one of the easiest/least expensive ways of achieving this is to link an HDMI decoder chip to an IP camera, in place of the actual camera module. HDMI decoder decodes to parallel RGB, and the IP camera encodes it to H.264 or H.265, depending on sophistication of the silicon.
The only real complexity is handing the external selection of resolutions (i.e. chosen by the HDMI source). If worst comes to worst, one could work around that by only advertising a single choice in the EDID information. The rest should just be making sure of electrical compatibility between the HDMI decoder and the camera SoC.
For an idea of price, I got a two piece IP camera module (camera on a separate board to the SoC) for around $30, and a multi-input video to parallel RGB decoder board for around $20. Mashing the two together would probably add around $10-20, I guess?
Yes, this just works, but you need to configure the video encoder ISP fot RGB. You also likely need a HDMI to CSI2 decoder. Few cameras use parallel pixel busses nowadays. For many Chinese camera chips you can easily find the SDK online.
So you can buy an HDMI to CSI2 adapter for a Raspberry Pi, for around $100, IIRC. Uses a Toshiba chip, I think it is the only one in existence. The camera SoC that I have is a HiSilicon3516, which can do 1080p30, using parallel RGB, which is a perfect fit for the AdaFruit HDMI-LCD adapter that I bought. (Hopefully!)
The real trick will be synchronizing the video signal from the AdaFruit board to the camera. For that I bought a couple of FPC40 breakout boards, and plan to mix and match the signals one by one to see what I can actually come up with. i.e. start with the camera connected to all pins on the SoC, recording at 1080p30, then start substituting pins from the HDMI interface to see how it affects the received signal from the camera. e.g. remove Green1 from the camera, and replace it with Green1 from the HDMI board.
Hopefully, I end up with all signals from the AdaFruit board connected, and the camera completely disconnected, and a meaningful signal still being recorded! :-D
look into PEPLINK bonded cellular. NO monthly fees.
These guys well even sell you (probably lease instead) a professionally made streaming backpack:
https://teradek.com/blogs/articles/4-reasons-to-love-cellular-bonding
Wonder if it served any role as inspiration for [Gunrun].
They do have equipment that will stream HDMI over Cellular networks. The last demo I did with them didn’t impress me however. The LiveU stuff is great when there’s no traffic in the area, but once people start facebooking, compression up the wazoo.
I don’t want to completely be a buzzkill but how is this a hack at all? It’s taking an off the shelf product, using it in it’s intended way, and putting it in a backpack.
Forget hack, this is no more DIY than pouring milk in your cereal in the morning.
🤣