Do I have the right stuff?

I'm kinda in the same boat waiting for someone more knowledgeable to answer about the capture stuff as I posted a similar thread last week.
I can however comment on a couple of your points.
If you have a choice I would go with 12 volt strips just due to Ohm's law. You can push further with higher voltage so you can get away with fewer power injection points. The PSU should have a label on the side that tells you how many amps it can provide on each rail....Like for 5v +, 12v + and so on.

This is what you need to look at to be able to tell, but I have some very old 300w PSUs that say they can give 20 amps on the 5v+ rail so you are most likely ok there. Rule of thumb I go by is never go past 80% of what is rated.
So doing some quick math and looking at the 2815 strip (12v) you linked we have it rated for Power: 34.5 watt/meter, 172.5 watt/16.4ft
So lets round to 175 watts which at 12 volts gives us just under 15 amps DC. 16 is 80% of 20 so I wouldn't use a power supply that can give less than 20 amps DC on the 12volt+ rail.
This is with 144 leds/meter though. Your choice of course, but you probably don't need that density for a nice ambient display. The power budget would be much less with less leds (duh, I know) and so would the price.

Keep us updated with your build. I'm interested to see how it goes as I'm still trying to buy (working) components for mine.

144Leds/m is not needed.
60Leds/m is a good compromise and you'll get perfect results with it.

Zitat von NeeeeB

144Leds/m is not needed.
60Leds/m is a good compromise and you'll get perfect results with it.

even with 30leds/m (i think) is more than okay.

advantage with less led is that you can run them on maximum brightness, which improves density of the colours. I've experimented with 60 Leds/m but its too bright, at least for me
now i am running the APA102 30 Leds/m on maximum brightness so there you go

a couple of pointers'

just use a powersource with a steady 5 volts and capable of providing minimum of 10amps or more.
my setup is 130 led's 30leds/m on APA102 provided with a selfmade frame on 4K 65inch tv. ( had to cut 20 leds)
i use a PSU type ATX with 5 and 12 volts lines. > capable of providing 30 A and more on 5volts.
It uses with PI and RCA converter about 3,5 amps

you dont need the "law of ohm" just provide 5 volts to the begin and end of the ledstrip so you will even out the power
make sure that you have enough amps to "feed" the ledstrip.
make sure you ground everything to ground (-)

144leds/m is way too much and will destract you from watching tv, don't take my word for it just try it and you will see.

buy ledstrip on aliexpress instead of ledstripshops, will save you at least half of your money

what Hyperion indicates of how much power your ledstrip needs, take about half of that number and you are right in the ballpark
goodluck!

Zitat von kouklo

The PSU I have can do 170W on 5V so the 60/M should go full brightness. The website says that a full 5M uses 90W, even if that was a mistake I still have 80W of wiggle room. If I don't use this PSU its just going to sit there doing nothing, so I may as well use it.

you are not reading what i am saying.

first of all the PSU only can provide a power, the device demands only power the PSU can deliver (or not because its too light).
it doesn't matter how much amps your PSU is, the only thing is that it should provide ( for basics) a minimum of 10 A

further of all, you don't need a 12volt strip. Somebody here said this but its not true, you can do it with only a STEADY and clean 5.0 volts.

good luck.

Zitat von kouklo

1-Is there any reason that a 12V wouldn't work with this?
2-If I go for the 5V will my PSU be enough to power the strips and the PI 3?
3-Are APA102 that much better than ws2815 (ws2812b)?

1; it works with a level shifter or arduino
2; your PSU will be plenty okay ( i use ATX too)
3; APA102 are quite okay, also experimented with WS2801, its just a matter of personal preference

its not a kit you can order and build immediately guy, there's a lot here constantly improving installations/settings etc.
i started with reading a lot on it on the internet and read a lot of forum topics and articles.

good luck with everything.

Zitat von kouklo

You make so good points @jeroen warmerdam, Ill go with the APA102 60/M and use my PSU.

Does anyone have any good info about splitters for 4K/HDR etc? Will one of the 2 splitters I posted work?

me and a friend of mine have ours from XOLORspace

And to buy your Led strip, the official "BTF Lightning" shop on Aliexpress will save you a lot of money as stated by @jeroen warmerdam .

https://btf-lighting.aliexpres…1000001.12.214627d85qhIi2

You're really unlucky, I order tons of stuff every week and it gets to France usually in 2 weeks, never more than 3.

Ah sorry...that forum displays funky flags sometimes and it currently says to me that you are in Spain...
Btw, BTF prices are great and quality is even better.
You can find BTF products on Amazon too, but they are at least twice more expensive...
Be patient and you'll save a good amount of money