I also started out with the imx8mq and am familiar with its limitations. Right now, my Reform uses the a311d while my second board has an ls1028a. When I still had all three platforms around I was looking for benchmarks which would make it easier to decide for a platform. Unfortunately, this is not that simple. For example the phoronix-test-suite contains a benchmark that uses mpv to measure decoding framerates. But according to the mpv developers that benchmark is faulty: regression: --term-status-msg missing from --log-file since 2fd34889 · Issue #13038 · mpv-player/mpv · GitHub
So if you know a better benchmark, I could try to run it on a311d and ls1028a so that you have some real numbers to decide.
Until then, here is my “general impression”: it depends.
So yes, the imx8mq can do 1080p (even in software) but it depends on the codec, the framerate and the encoder settings. It also very much depends on whether you do hardware decoding or not. If your material is 1080p h264 then the imx8mq can even decode 60 fps without any issues. Theoretically the hardware decoder (hantro) can also do h265 but there are still bugs on the software side which result in really weird artifacts and color shifts depending on the video you try playing. So on my imx8mq I was preferring h264 and when it had to be h265 then i had to reduce resolution to 720p because that had to be software decoded (mpv). And then there is also the issue that firefox will not utilize the hardware decoder of the imx8mq and even though mpv managed to do 1080p@30 in software (for h264), firefox is far from the performance of mpv.
The main videos I watch are twitch (1080p@60 h264), youtube (1080p@60 vp9) and some anime (firstname.lastname@example.org h265 10bit) and the ls1028a has no hardware decoder. I’m also not much interested in watching youtube and twitch in a browser, so all my tests on ls1028a were with mpv and the yt-dlp backend. With that in mind, I can tell you that the ls1028a was not powerful enough to decode 1080p@60 h264 twitch streams, for example. I have some harder numbers for some cpu-loads which I documented here:
So indeed the A75 cores individually are faster than an individual core of the imx8mq but for loads that can utilize all cores (which video decoders are also able to do) the imx8mq is able to beat the ls1028a because it just has twice the number of (a bit slower) cores.
Finally, lets talk about the a311d bananapi. It’s my main platform right now and as vkoskiv already hinted in their response to my post above, its performance is far above that of imx8mq and ls1028a. I just tried it out and yes, you can play 1080p in firefox fullscreen without visible frame drops. If you send me a link, I can show you the CPU usage graphs so that you get an idea how taxing this is for the chip. As I said earlier, I’m mostly an mpv user and I have yet to find some material that the a311d is not able to handle (of course this means 1080p only – more doesn’t make sense with the display of the reform).
Bottom line: if you want raw performance, then there is not even a competition: a311d wins hands down over ls1028a – not only when it’s about software video decoding.