Issue with conversion to mp4

[TanmayHiremath]

When I'm trying to convert https://scalelite2.fossee.in/playback/presentation/2.0/playback.html?meetingId=99057b15d0c38982911dd5b48efb5c63649e41b4-1613011815604 export this recording to mp4, the output video is stuck after 5-6 seconds, whereas the webm file generated is perfectly fine.

/home/captain/Lecture.mp4
/home/captain/Downloads/Lecture.webm
stderr: ffmpeg version 4.3.1-0york0~18.04 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
  configuration: --prefix=/usr --extra-version='0york0~18.04' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libzimg --enable-pocketsphinx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared

stderr:   libavutil      56. 51.100 / 56. 51.100
  libavcodec     58. 91.100 / 58. 91.100
  libavformat    58. 45.100 / 58. 45.100
  libavdevice    58. 10.100 / 58. 10.100
  libavfilter     7. 85.100 /  7. 85.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  7.100 /  5.  7.100
  libswresample   3.  7.100 /  3.  7.100
  libpostproc    55.  7.100 / 55.  7.100

stderr: Input #0, matroska,webm, from '/home/captain/Downloads/Lecture.webm':
  Metadata:
    encoder         : Chrome
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0(eng): Audio: opus, 48000 Hz, stereo, fltp
stderr:  (default)
    Stream #0:1(eng): Video: h264 (Constrained Baseline), yuv420p(progressive), 1280x720, SAR 1:1 DAR 16:9, 59.94 fps, 59.94 tbr, 1k tbn, 2k tbc (default)

stderr: Stream mapping:
  Stream #0:1 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:0 -> #0:1 (opus (native) -> aac (native))
Press [q] to stop, [?] for help

stderr: [libx264 @ 0x55b7ea0d3d40] using SAR=1/1

stderr: [libx264 @ 0x55b7ea0d3d40] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2

stderr: [libx264 @ 0x55b7ea0d3d40] profile High, level 4.2

stderr: [libx264 @ 0x55b7ea0d3d40] 264 - core 155 r2917 0a84d98 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=18 lookahead_threads=5 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=1 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=10 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00

stderr: Output #0, mp4, to '/home/captain/Lecture.mp4':
  Metadata:
    encoder         : Lavf58.45.100

stderr:     Stream #0:0(eng): Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 59.94 fps, 60k tbn, 59.94 tbc (default)
    Metadata:
      encoder         : Lavc58.91.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      encoder         : Lavc58.91.100 aac

stderr: frame=    2 fps=0.0 q=0.0 size=       0kB time=00:00:14.23 bitrate=   0.0kbits/s speed=28.5x    
stderr: frame=    2 fps=2.0 q=0.0 size=       0kB time=00:00:28.69 bitrate=   0.0kbits/s speed=28.7x    
stderr: frame=    2 fps=1.3 q=0.0 size=       0kB time=00:00:43.76 bitrate=   0.0kbits/s speed=29.2x    
stderr: frame=    2 fps=1.0 q=0.0 size=       0kB time=00:00:57.44 bitrate=   0.0kbits/s speed=28.7x    
stderr: frame=    2 fps=0.8 q=0.0 size=       0kB time=00:01:11.36 bitrate=   0.0kbits/s speed=28.5x    
stderr: [mp4 @ 0x55b7ea0f0980] Starting second pass: moving the moov atom to the beginning of the file

stderr: frame=    2 fps=0.7 q=-1.0 Lsize=      62kB time=00:01:19.94 bitrate=   6.3kbits/s speed=28.1x    
video:3kB audio:22kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 
stderr: 148.519852%

stderr: [libx264 @ 0x55b7ea0d3d40] frame I:1     Avg QP:15.02  size:  1825
[libx264 @ 0x55b7ea0d3d40] frame P:1     Avg QP:19.31  size:   130
[libx264 @ 0x55b7ea0d3d40] mb I  I16..4: 97.6%  0.8%  1.6%

stderr: [libx264 @ 0x55b7ea0d3d40] mb P  I16..4:  5.1%  0.0%  0.0%  P16..4:  0.0%  0.8%  0.0%  0.0%  0.0%    skip:94.1%
[libx264 @ 0x55b7ea0d3d40] 8x8 transform intra:0.8%
[libx264 @ 0x55b7ea0d3d40] coded y,uvDC,uvAC intra: 1.7% 2.1% 1.3% inter: 0.0% 0.0% 0.0%
[libx264 @ 0x55b7ea0d3d40] i16 v,h,dc,p: 82% 16%  2%  0%
[libx264 @ 0x55b7ea0d3d40] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  9% 28% 21% 17%  2%  0%  5%  2% 17%
[libx264 @ 0x55b7ea0d3d40] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 25% 22% 24%  8%  4%  5%  4%  4%  4%
[libx264 @ 0x55b7ea0d3d40] i8c dc,h,v,p: 94%  5%  1%  0%
[libx264 @ 0x55b7ea0d3d40] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x55b7ea0d3d40] kb/s:234.37

stderr: [aac @ 0x55b7ea0ef4c0] Qavg: 65536.000

child process exited with code 0
Convertion done to here: /home/captain/Lecture.mp4
successfully deleted /home/captain/Downloads/Lecture.webm```

[amitnactus]

I am also facing similar issue. Request you to please check and do the needful asap.