Edge artifacts at >8K

[Brendan Bolles]

I'm getting some edge artifacts at resolutions larger than 8K, such as 8192x1494.

I'm using the latest build of FFmpeg, HEVC encoder version 2.8+52-c258d214c97.

Here's a sample log:

ffmpeg-4.0.3b1 -loglevel verbose -y -i H265_bug_2xHD/H265_bug_2xHD_v001.mov -vf "scale=8192x1494" -c:v libx265 -tag:v hvc1 -pix_fmt yuv420p -crf 20 -x265-params keyint=10 FFmpeg_H265_bug_2xHD_v001.mp4

ffmpeg version N-91528-ged647ab79f-tessus Copyright (c) 2000-2018 the FFmpeg developers built with Apple LLVM version 9.1.0 (clang-902.0.39.2) configuration: --cc=/usr/bin/clang --prefix=/opt/ffmpeg --extra-version=tessus --enable-avisynth --enable-fontconfig --enable-gpl --enable-libaom --enable-libass --enable-libbluray --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libmysofa --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopus --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-version3 --pkg-config-flags=--static --disable-ffplay libavutil 56. 18.102 / 56. 18.102 libavcodec 58. 22.100 / 58. 22.100 libavformat 58. 17.101 / 58. 17.101 libavdevice 58. 4.101 / 58. 4.101 libavfilter 7. 26.100 / 7. 26.100 libswscale 5. 2.100 / 5. 2.100 libswresample 3. 2.100 / 3. 2.100 libpostproc 55. 2.100 / 55. 2.100 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Volumes/Rodan/Staff_Folders/Brendan_Bolles/Renders/H265_bug_2xHD/H265_bug_2xHD_v001.mov': Metadata: major_brand : qt
minor_version : 537199360 compatible_brands: qt
Duration: 00:00:05.00, start: 0.000000, bitrate: 329200 kb/s Stream #0:0(eng): Video: prores, 1 reference frame (apch / 0x68637061), yuv422p10le(tv, bt709, progressive), 3840x2160, 327522 kb/s, SAR 1:1 DAR 16:9, 30 fps, 30 tbr, 30 tbn, 30 tbc (default) Metadata: handler_name : Apple Video Media Handler encoder : Apple ProRes 422 (HQ) timecode : 00:00:00:00 Stream #0:1(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default) Metadata: handler_name : Time Code Media Handler timecode : 00:00:00:00 Stream mapping: Stream #0:0 -> #0:0 (prores (native) -> hevc (libx265)) Press [q] to stop, [?] for help [Parsed_scale_0 @ 0x7fb763a00000] w:8192 h:1494 flags:'bicubic' interl:0 [graph 0 input from stream 0:0 @ 0x7fb763a005c0] w:3840 h:2160 pixfmt:yuv422p10le tb:1/30 fr:30/1 sar:1/1 sws_param:flags=2 [Parsed_scale_0 @ 0x7fb763a00000] w:3840 h:2160 fmt:yuv422p10le sar:1/1 -> w:8192 h:1494 fmt:yuv420p sar:83/256 flags:0x4 x265 [info]: HEVC encoder version 2.8+52-c258d214c978 x265 [info]: build info [Mac OS X][clang 9.1.0][64 bit] 8bit+10bit+12bit x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 x265 [info]: Main profile, Level-6 (Main tier) x265 [info]: Thread pool created using 24 threads x265 [info]: Slices : 1 x265 [info]: frame threads / pool features : 4 / wpp(24 rows) x265 [info]: Coding QT: max CU size, min CU size : 64 / 8 x265 [info]: Residual QT: max TU size, max depth : 32 / 1 inter / 1 intra x265 [info]: ME / range / subpel / merge : hex / 57 / 2 / 2 x265 [info]: Keyframe min / max / scenecut / bias: 1 / 10 / 40 / 5.00 x265 [info]: Lookahead / bframes / badapt : 20 / 4 / 2 x265 [info]: b-pyramid / weightp / weightb : 1 / 1 / 0 x265 [info]: References / ref-limit cu / depth : 3 / on / on x265 [info]: AQ: mode / str / qg-size / cu-tree : 1 / 1.0 / 32 / 1 x265 [info]: Rate Control / qCompress : CRF-20.0 / 0.60 x265 [info]: tools: rd=3 psy-rd=2.00 rskip signhide tmvp strong-intra-smoothing x265 [info]: tools: lslices=8 deblock sao Output #0, mp4, to '/Volumes/Rodan/Staff_Folders/Brendan_Bolles/Renders/H265_bug_2xHD/FFmpeg_H265_bug_2xHD_v001.mp4': Metadata: major_brand : qt
minor_version : 537199360 compatible_brands: qt
encoder : Lavf58.17.101 Stream #0:0(eng): Video: hevc (libx265), 1 reference frame (hvc1 / 0x31637668), yuv420p, 8192x1494 [SAR 83:256 DAR 16:9], q=2-31, 0.03 fps, 15360 tbn, 30 tbc (default) Metadata: handler_name : Apple Video Media Handler timecode : 00:00:00:00 encoder : Lavc58.22.100 libx265 frame= 150 fps=2.9 q=-0.0 Lsize= 3995kB time=00:00:04.90 bitrate=6678.3kbits/s speed=0.0947x
video:3990kB audio:0kB subtitle:0kB other streams:0kB global headers:2kB muxing overhead: 0.128535% Input file #0 (/Volumes/Rodan/Staff_Folders/Brendan_Bolles/Renders/H265_bug_2xHD/H265_bug_2xHD_v001.mov): Input stream #0:0 (video): 150 packets read (204701648 bytes); 150 frames decoded; Input stream #0:1 (data): 0 packets read (0 bytes); Total: 150 packets (204701648 bytes) demuxed Output file #0 (/Volumes/Rodan/Staff_Folders/Brendan_Bolles/Renders/H265_bug_2xHD/FFmpeg_H265_bug_2xHD_v001.mp4): Output stream #0:0 (video): 150 frames encoded; 150 packets muxed (4085254 bytes); Total: 150 packets (4085254 bytes) muxed [AVIOContext @ 0x7fb761e00240] Statistics: 2 seeks, 19 writeouts x265 [info]: frame I: 15, Avg QP:15.36 kb/s: 43407.14 x265 [info]: frame P: 16, Avg QP:17.11 kb/s: 8115.39 x265 [info]: frame B: 119, Avg QP:20.33 kb/s: 1675.33 x265 [info]: Weighted P-Frames: Y:0.0% UV:0.0% x265 [info]: consecutive B-frames: 3.2% 0.0% 0.0% 3.2% 93.5%

encoded 150 frames in 51.68s (2.90 fps), 6535.45 kb/s, Avg QP:19.49 [AVIOContext @ 0x7fb761d00580] Statistics: 204767188 bytes read, 3 seeks sf23:~ bbolles$