overlay_cuda: green line on overlaid video

[pero]

Hello,

With filter "overlay_cuda", the overlaid video has a green line at the bottom. It only happens, if the overlaid video was scaled down with "scale_npp" before overlaying. Screenshot attached.

How to reproduce:

ffmpeg -y -hwaccel cuvid -hwaccel_output_format cuda -c:v h264_cuvid -i v1.mp4 -hwaccel cuvid -hwaccel_output_format cuda -c:v h264_cuvid -i v2.mp4 -filter_complex "[1:v]scale_npp=w=640:h=360[scaled];[0:v][scaled]overlay_cuda=x=0:y=0" -an -c:v h264_nvenc output.mp4

Output:

ffmpeg version N-103787-ga487635b85 Copyright (c) 2000-2021 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.3.0-17ubuntu1~20.04)
  configuration: --enable-filter=overlay_cuda --enable-nonfree --enable-cuda-nvcc --enable-libnpp --extra-cflags=-I/usr/local/cuda/include --extra-ldflags=-L/usr/local/cuda/lib64
  libavutil      57.  6.100 / 57.  6.100
  libavcodec     59.  9.100 / 59.  9.100
  libavformat    59.  5.100 / 59.  5.100
  libavdevice    59.  0.101 / 59.  0.101
  libavfilter     8.  9.100 /  8.  9.100
  libswscale      6.  1.100 /  6.  1.100
  libswresample   4.  0.100 /  4.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'v1.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.26.100
  Duration: 00:00:56.00, start: 0.000000, bitrate: 1489 kb/s
  Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1351 kb/s, 25 fps, 25 tbr, 90k tbn (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
  Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]
Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'v2.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.26.100
  Duration: 00:01:28.01, start: 0.000000, bitrate: 1487 kb/s
  Stream #1:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1350 kb/s, 25 fps, 25 tbr, 90k tbn (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
  Stream #1:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]
Stream mapping:
  Stream #0:0 (h264_cuvid) -> overlay_cuda:main
  Stream #1:0 (h264_cuvid) -> scale_npp
  overlay_cuda -> Stream #0:0 (h264_nvenc)
Press [q] to stop, [?] for help
Output #0, mp4, to 'output.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf59.5.100
  Stream #0:0: Video: h264 (Main) (avc1 / 0x31637661), cuda(tv, progressive), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 2000 kb/s, 25 fps, 12800 tbn (default)
    Metadata:
      encoder         : Lavc59.9.100 h264_nvenc
    Side data:
      cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 4000000 vbv_delay: N/A

Thank you!

[pero]

I've just realized that it is working with scale_cuda filter instead of scale_npp.
I don't know if I should close this or leave it open?

[Timo R.]

This should be fixed since 37745b49049d4dbb5aa4ea84bcc289ed511971f9