artifacts using delogo filter on some videos

[Mengye Lyu]

Summary of the bug:

When using delogo filter on some videos, the areas delogoed will sometimes show artifacts, like the TV snow noise. I tried v4.1 and the lastest build on linux and windows, all having this problem. I processed around 10k videos, a few percent of them had this problem.
I also tried to first re-encode the videos to others format, did not help fix the problem.

How to reproduce:

command:
 ffmpeg -i D:/782848_cut.mp4 -vf "delogo=x=62:y=41:w=197:h=101" D:/782848_cut_delogo.mp4 -y

ffmpeg version N-94455-g01994c93db Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9.1.1 (GCC) 20190716
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enabl
e-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enab
le-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enabl
e-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 -
-enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enabl
e-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --en
able-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-l
ibopenmpt
  libavutil      56. 33.100 / 56. 33.100
  libavcodec     58. 55.100 / 58. 55.100
  libavformat    58. 30.100 / 58. 30.100
  libavdevice    58.  9.100 / 58.  9.100
  libavfilter     7. 58.100 /  7. 58.100
  libswscale      5.  6.100 /  5.  6.100
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:/782848_cut.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2mp41
    encoder         : Lavf58.12.100
  Duration: 00:00:20.17, start: 0.000000, bitrate: 2432 kb/s
    Stream #0:0(und): Video: mpeg4 (Simple Profile) (mp4v / 0x7634706D), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 2106 kb/s
, 25.05 fps, 25 tbr, 10000k tbn, 25 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: mp3 (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 319 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg4 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (mp3 (mp3float) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 000002d530180140] using SAR=1/1
[libx264 @ 000002d530180140] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 000002d530180140] profile High, level 3.1, 4:2:0, 8-bit
[libx264 @ 000002d530180140] 264 - core 158 r2984 3759fcb - H.264/MPEG-4 AVC codec - Copyleft 2003-2019 - http://www.vid
eolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed
_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 looka
head_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b
_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookah
ead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'D:/782848_cut_delogo.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2mp41
    encoder         : Lavf58.30.100
    Stream #0:0(und): Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 25 fps,
12800 tbn, 25 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc58.55.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      encoder         : Lavc58.55.100 aac
frame=  505 fps= 88 q=-1.0 Lsize=    5675kB time=00:00:20.17 bitrate=2303.9kbits/s speed=3.53x
video:5340kB audio:320kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.261392%
[libx264 @ 000002d530180140] frame I:3     Avg QP:19.33  size: 37616
[libx264 @ 000002d530180140] frame P:461   Avg QP:20.26  size: 11030
[libx264 @ 000002d530180140] frame B:41    Avg QP:21.11  size:  6583
[libx264 @ 000002d530180140] consecutive B-frames: 84.8% 12.7%  1.8%  0.8%
[libx264 @ 000002d530180140] mb I  I16..4: 39.7% 59.1%  1.2%
[libx264 @ 000002d530180140] mb P  I16..4: 11.5% 14.9%  0.3%  P16..4: 29.1%  5.3%  2.7%  0.0%  0.0%    skip:36.2%
[libx264 @ 000002d530180140] mb B  I16..4:  5.9%  6.1%  0.0%  B16..8: 34.8%  3.5%  0.5%  direct: 9.8%  skip:39.3%  L0:72
.5% L1:16.8% BI:10.6%
[libx264 @ 000002d530180140] 8x8 transform intra:55.5% inter:85.2%
[libx264 @ 000002d530180140] coded y,uvDC,uvAC intra: 15.7% 40.7% 5.6% inter: 12.6% 14.9% 1.1%
[libx264 @ 000002d530180140] i16 v,h,dc,p: 62% 25% 12%  1%
[libx264 @ 000002d530180140] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 26% 17% 50%  3%  1%  1%  1%  1%  2%
[libx264 @ 000002d530180140] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 45% 25% 13%  2%  5%  3%  3%  2%  2%
[libx264 @ 000002d530180140] i8c dc,h,v,p: 44% 23% 31%  2%
[libx264 @ 000002d530180140] Weighted P-Frames: Y:1.7% UV:0.7%
[libx264 @ 000002d530180140] ref P L0: 73.2% 11.9% 11.1%  3.7%  0.1%
[libx264 @ 000002d530180140] ref B L0: 84.8% 14.9%  0.4%
[libx264 @ 000002d530180140] ref B L1: 99.2%  0.8%
[libx264 @ 000002d530180140] kb/s:2165.42
[aac @ 000002d5301e7bc0] Qavg: 489.392

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

[Mengye Lyu]

input file

[Carl Eugen Hoyos]

Regression since e74f1a121e94587d0df8a7f5a12f2d48a974695c

[Jun Zhao]

fixed by 9f353e376b161eb16a78fd7ad727c9513ac60d13

[Jun Zhao]

fixed by 9f353e376b161eb16a78fd7ad727c9513ac60d13