And yes it eats up HDCP streams no problem.
Show this thread
I just got one of these and I would've documented it, but @Ascii211 already did, so there you go.
It's surprisingly good bang/buck, though the MJPEG quality isn't great (esp. the chroma); definitely better on YUV but you lose framerate.
I have some USB3 units ordered. We'll seehttps://twitter.com/Ascii211/status/1268631069051453448 …
-
-
-
Looks like you don't get all 1920 pixels horizontally, though. It seems to be more like half the horizontal res, due to some kind of filtering. You do get 1080 lines though. So 960x1080 effectively? First image is the cheap thing, second is an AverMedia LGP2 (crop of 1080p frame)pic.twitter.com/kwANLY2wWZ
Show this thread -
At 1280x720 you do get all the pixels you paid for, though, but there is some kind of horizontal sharpening being applied. Again, compared against the LGP2.pic.twitter.com/NREwPMiR0o
Show this thread -
(Right click and open those images at original resolution to get the proper idea; Twitter always scales by default)
Show this thread -
I would rate the artifacts at 720p as a bit worse than the LGP2, but not terrible (chinese left, LGP2 right). This is after adjusting the brightness/contrast/saturation/hue on both to attempt to match the original image (neither has good defaults).pic.twitter.com/sVYN4OVp5t
Show this thread -
So I would call this a fairly capable 720p capture card overall, and only slightly lower performance at that resolution than devices that cost 10 times as much. At 1080p things are a bit messier, but it does work.
Show this thread -
So it turns out they report audio at 1ch 96kHz, but it's actually 2ch 48kHz. Currently testing a quirk patch for Linux, assuming it works as intended expect it in a stable series near you once it percolates through the pipeline.
Show this thread -
FWIW, interpreting 48k stereo as 96k mono (and downsampling to 48k, because you are, right?) is mathematically equivalent to a clean mono mixdown except one channel is delayed by 0.5 samples, which is negligible. So it's safe to use the card on Win/Mac and pretend it's mono.
Show this thread -
Basically for mono (center panned) content you'll get a slight high frequency rolloff (4dB or so at Nyquist = 24kHz), and hard panned content will sound fine with no distortion.
Show this thread -
OMG. I think this is why they claim 96kHz mono. Assuming this isn't a bug in my USB config... these things have a hardware bug which briefly swaps the channels intermittently. Every second or so. So they probably set it to 96k mono as a hack so you won't notice!pic.twitter.com/XGnJ9OQogJ
Show this thread -
I have a suspicion as to what causes this and Linux might already have a quirk to deal with it. I think this happens when the USB transfer size is not a multiple of the number of channels.
Show this thread -
Yup, QUIRK_AUDIO_ALIGN_TRANSFER fixed it... and now the channels are just backwards. Lovely. At least it seems they're *consistently* backwards. Hopefully there's a way of quirking this in ALSA...
Show this thread -
Patch for the kernel quirk sent to alsa-devel (cc stable).
Show this thread
End of conversation
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.