2nd pass won't start..."file size too small"

[Toothache]

Enabling 'x265>Rate Control->Rate Distortion Optimization-> Scene cut aware quantization' seems to allow using 2pass encoding.
Seems to be a known bug in the latest x265 build, see: https://bitbucket.org/multicoreware/x265...with-32-15

Cu Selur

How do I enable that in Hybrid? Does enabling it change anything for the resulting file? I mean, are there any drawbacks?

[Selur]

Enable 'x265->Rate Control->Rate Distortion Optimization-> Scene cut aware quantization' is how you enable it in Hybrid.
encoding might be slower but quality can be a bit better,...

[Selur]

x265 devs released a new build which fixes the problem.
-> will send you a link to a dev version with that x265 build for testing in a few minutes

Cu Selur

[Toothache]

Thanks, that worked. So for the record, it was a bug in x265, which has now been rectified.

[Selur]

yup, seems like it was a small bug in x265 which they fixed in:
https://bitbucket.org/multicoreware/x265...f5c4e02ac7

Cu Selur

[firsak]

I'm still getting the same error with ffmpeg-20200102-81172b5-win64-static.

G:\Video\auto\test>ffmpeg -i 2015_0101_142521_006.mp4 -c:v libx265 -b:v 4000k -x265-params pass=2 -c:a copy output.mp4
ffmpeg version git-2020-01-02-81172b5 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.2.1 (GCC) 20191125
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-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 --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 38.100 / 56. 38.100
  libavcodec     58. 65.102 / 58. 65.102
  libavformat    58. 35.101 / 58. 35.101
  libavdevice    58.  9.102 / 58.  9.102
  libavfilter     7. 70.101 /  7. 70.101
  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 '2015_0101_142521_006.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.20.100
  Duration: 00:07:28.54, start: 0.000000, bitrate: 20189 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080, 20067 kb/s, SAR 1:1 DAR 16:9, 30 fps, 30 tbr, 30k tbn, 60 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 112 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> hevc (libx265))
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
x265 [info]: HEVC encoder version 3.2+15-04db2bfee5d6
x265 [info]: build info [Windows][GCC 9.2.1][64 bit] 8bit+10bit
x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
x265 [info]: Main profile, Level-4 (Main tier)
x265 [info]: Thread pool created using 16 threads
x265 [info]: Slices                              : 1
x265 [info]: frame threads / pool features       : 4 / wpp(17 rows)
x265 [error]: different scenecut setting than first pass (40 vs 40)
[libx265 @ 000000e2152bf080] Cannot open libx265 encoder.
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Conversion failed!

[Selur]

Bug has been fixed in x265 since end of November (https://bitbucket.org/multicoreware/x265...f5c4e02ac7).
Running:

ffmpeg -i "F:\TestClips&Co\files\test.avi" -c:v libx265 -b:v 4000k -x265-params pass=1 -c:a copy "E:\Output\teste.mp4"

and then

ffmpeg -i "F:\TestClips&Co\files\test.avi" -c:v libx265 -b:v 4000k -x265-params pass=2 -c:a copy "E:\Output\teste.mp4"

works fine here, so the problem is with the FFmpeg build you use.
Seems like the FFmpeg build you use is build with an old libx265 version.

Cu Selur