K-ON! Live, Let's Go!
It was held 4 years ago in Yokohama, and later released in BD. However I didn't find any satisfying BDRips, so I've done one on my own.
Explanation why this is encoded in 1920x540 (and use --sar 1:2 to force players to output in 16:9)
For the source video in BD, every two consecutive rows are identical(except for background quantization noise), meaning the images look like:
02468
02468
13579
13579
......
if left alone, it will result in blurring and aliasing(see the first picture below); remove duplicated rows and let video players(I'd recommend those with madVR ) do the twice-height-resizing, the situation got much better(see the second picture below):
pp: adaptive denoise, deband, deblock, sharpen
major encoding parameters: ref=10 / deblock=1:0:0 / me=tesa / subme=10 / fade_compensate=0.00 / psy_rd=0.80:0.00 / me_range=24 / fast_pskip=0 / chroma_qp_offset=-2 / fgo=0 / bframes=8 / b_adapt=2 / weightb=1 / weightp=2 / keyint=720 / keyint_min=1 / mbtree=1 / crf=19.0000 / qcomp=0.70 / aq=3:0.90 / aq2=0 / aq3=0