That’s the end of the good news, however. If you play 1080i content on the PS4, you’ll find that the system deinterlaces it, and does a poor job of it. There doesn’t seem to be any semi-advanced motion-adaptive deinterlacing on the PS4 at all, with the entire screen (and not just the moving areas) being deinterlaced with a fairly crude algorithm. Visually, that translates into fine details flickering slightly. Of course, it’s more obvious in test charts than it is in content, but the resolution is being lost either way.
Nearly all films are stored at 24p so don’t count on seeing any issues with those, but if you play a video-based concert or documentary on the machine, you’ll be getting lessened vertical resolution compared to what you’d get from a better Blu-ray player such as the PS3, or nearly any standalone player.
Don’t think about setting the output to 1080i to send 1080i discs out in their native format, either: this compounds the problem. Even with the output set to 1080i, all 1080i content is deinterlaced internally and then output. There’s no native path for 1080i Blu-ray content on the PS4 (yet?), everything goes through the sub-par 1080p conversion process.
The diagonal interpolation test (which tests for a player’s ability to smooth jaggies during interlace to progressive conversion) didn’t return good results either, with jaggies being obvious on steep angles.
Unsurprisingly with all of this in mind, there is no provision made for film mode deinterlacing (detecting the presence of film content stored in an interlaced signal). Just so it’s clear, here are the tests from the 60hz tests on the Spears & Munsil disc:
2-2 (30fps inside 60i): Fail
2-2-2-4: Fail
2-3-2-3 PF-T (24fps inside 60i with MPEG metadata): Fail
2-3-2-3 (24fps inside 60i): Fail
2-3-2-3: Fail
2-3-3-2: Fail
3-2-3-2-2: Fail
5-5: Fail
6-4: Fail
8-7-8-7: Fail
Time-adjusted: Fail
Likewise, for European users watching European content (BBC TV shows are an obvious example), it’s worth knowing that the Blu-ray format does not have provision for 25p, so all of this content is encoded at 50i, and accordingly falls foul of the PS4′s lack of deinterlacing capabilities. With 1080i HD content, this is actually not a gigantic problem, and we imagine most users won’t notice owed to the high HD resolution masking the resolution loss. It’s still poorer quality than many standalone players, however.
It’s a strange decision on Sony’s part, because when first launched, the PS3 system simply output 1080i content as 1080i (natively), meaning that the other components in the user’s AV system (AV receiver or TV) would do the deinterlacing. We’d hope this is something Sony addresses with a system update – either give us good deinterlacing with film mode detection, or just output the 1080i content as pure 1080i and let another device that has the same capabilities take care of it.
