Body: <p>This is a follow-up from my previous question <a href="https://video.stackexchange.com/questions/27498/">here</a>. Basically, I'm trying to use <code>FFmpeg</code>'s loop filter to freeze some frames and insert black frames. It's very weird; I swear it was working a few days ago, but now only the blackframe insertion works, the freezing frames doesn't work. So just no frozen frames inside. I don't know what's going wrong?!</p>
  
  <p>Here is my command. I also updated my ffmpeg to the latest version just now:</p>
  
  <pre><code>fn="sample.mp4"
  
  #
  ffmpeg -y -i "${fn}" -ss 00:00:05 -to 00:00:06 -r 1/1 _05.png
  ffmpeg -y -i "${fn}" -ss 00:00:10 -to 00:00:11 -r 1/1 _10.png
  ffmpeg -y -i "${fn}" -ss 00:00:15 -to 00:00:16 -r 1/1 _15.png
  ffmpeg -y -i "${fn}" -ss 00:00:20 -to 00:00:21 -r 1/1 _20.png
  ffmpeg -y -i "${fn}" -ss 00:00:25 -to 00:00:26 -r 1/1 _25.png
  ffmpeg -y -i "${fn}" -ss 00:00:30 -to 00:00:31 -r 1/1 _30.png
  ffmpeg -y -i "${fn}" -ss 00:00:35 -to 00:00:36 -r 1/1 _35.png
  
  #
  ffmpeg -y -i "${fn}" \
  -i _05.png \
  -i _10.png \
  -i _15.png \
  -i _20.png \
  -i _25.png \
  -i _30.png \
  -i _35.png \
  -filter_complex "
  [0:v]trim=0:5,setpts=PTS-STARTPTS[0v_1];
  [1:v]loop=loop=25*3:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=2:d=1[pause1];
  [0:v]trim=5:10,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_2];
  [2:v]loop=loop=25*4:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=1[pause2];
  [0:v]trim=10:15,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_3];
  [3:v]loop=loop=25*5:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=2[pause3];
  [0:v]trim=15:20,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_4];
  [4:v]loop=loop=25*6:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=3[pause4];
  [0:v]trim=20:25,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_5];
  [5:v]loop=loop=25*7:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=4[pause5];
  [0:v]trim=25:30,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_6];
  [6:v]loop=loop=25*5:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=2[pause6];
  [0:v]trim=30:35,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_7];
  [7:v]loop=loop=25*3:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -&gt; fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=2:d=1[pause7];
  [0:v]trim=35,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_8];
  
  [0v_1][pause1]
  [0v_2][pause2]
  [0v_3][pause3]
  [0v_4][pause4]
  [0v_5][pause5]
  [0v_6][pause6]
  [0v_7][pause7]
  [0v_8]
  concat=n=15:a=0:v=1[v]
  " -map '[v]' -an "freeze.mp4"
  </code></pre>
  
  <p>And here is the whole log (truncating some initial logs for PNG saving due to size limit):</p>
  
  <pre><code>ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (h264 (native) -&gt; png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_25.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.8 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.817x
  video:663kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (h264 (native) -&gt; png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_30.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.7 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.715x
  video:503kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (h264 (native) -&gt; png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_35.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.6 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.637x
  video:539kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Input #1, png_pipe, from '_05.png':
    Duration: N/A, bitrate: N/A
      Stream #1:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #2, png_pipe, from '_10.png':
    Duration: N/A, bitrate: N/A
      Stream #2:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #3, png_pipe, from '_15.png':
    Duration: N/A, bitrate: N/A
      Stream #3:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #4, png_pipe, from '_20.png':
    Duration: N/A, bitrate: N/A
      Stream #4:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #5, png_pipe, from '_25.png':
    Duration: N/A, bitrate: N/A
      Stream #5:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #6, png_pipe, from '_30.png':
    Duration: N/A, bitrate: N/A
      Stream #6:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #7, png_pipe, from '_35.png':
    Duration: N/A, bitrate: N/A
      Stream #7:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  [Parsed_drawtext_3 @ 0x6b53ec0] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_9 @ 0x6b5de40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_15 @ 0x6a1a780] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_21 @ 0x6a11940] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_27 @ 0x6b59f40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_33 @ 0x6a12880] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_39 @ 0x698d740] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  Stream mapping:
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #0:0 (h264) -&gt; trim
    Stream #1:0 (png) -&gt; loop
    Stream #2:0 (png) -&gt; loop
    Stream #3:0 (png) -&gt; loop
    Stream #4:0 (png) -&gt; loop
    Stream #5:0 (png) -&gt; loop
    Stream #6:0 (png) -&gt; loop
    Stream #7:0 (png) -&gt; loop
    concat -&gt; Stream #0:0 (libx264)
  Press [q] to stop, [?] for help
  [Parsed_drawtext_3 @ 0x6f3e480] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_9 @ 0x6f4ec00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_15 @ 0x6f57e00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_21 @ 0x6f65600] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_27 @ 0x6f6ed00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_33 @ 0x6f79c40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_39 @ 0x6f84dc0] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [libx264 @ 0x68fb900] using SAR=8/9
  [libx264 @ 0x68fb900] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
  [libx264 @ 0x68fb900] profile Progressive High, level 3.0, 4:2:0, 8-bit
  [libx264 @ 0x68fb900] 264 - core 157 r2969 d4099dd - H.264/MPEG-4 AVC codec - Copyleft 2003-2019 - http://www.videolan.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 lookahead_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_lookahead=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 'freeze.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc (default)
      Metadata:
        encoder         : Lavc58.52.100 libx264
      Side data:
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  frame= 1351 fps= 75 q=-1.0 Lsize=    5080kB time=00:00:44.97 bitrate= 925.2kbits/s dup=0 drop=5 speed=2.49x
  video:5064kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.321138%
  [libx264 @ 0x68fb900] frame I:19    Avg QP:18.75  size: 30579
  [libx264 @ 0x68fb900] frame P:424   Avg QP:22.86  size:  7793
  [libx264 @ 0x68fb900] frame B:908   Avg QP:26.77  size:  1431
  [libx264 @ 0x68fb900] consecutive B-frames:  5.8% 11.5%  6.2% 76.4%
  [libx264 @ 0x68fb900] mb I  I16..4: 11.1% 63.3% 25.6%
  [libx264 @ 0x68fb900] mb P  I16..4:  1.6%  6.2%  1.0%  P16..4: 45.2% 16.3%  8.6%  0.0%  0.0%    skip:21.0%
  [libx264 @ 0x68fb900] mb B  I16..4:  0.3%  0.5%  0.1%  B16..8: 33.2%  3.4%  0.6%  direct: 1.3%  skip:60.6%  L0:47.5% L1:46.2% BI: 6.3%
  [libx264 @ 0x68fb900] 8x8 transform intra:66.7% inter:72.0%
  [libx264 @ 0x68fb900] coded y,uvDC,uvAC intra: 52.5% 70.2% 34.8% inter: 11.4% 19.5% 0.9%
  [libx264 @ 0x68fb900] i16 v,h,dc,p: 55% 14% 10% 22%
  [libx264 @ 0x68fb900] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28% 13% 22%  5%  6%  8%  6%  7%  5%
  [libx264 @ 0x68fb900] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 23% 14% 12%  7% 10% 10%  8%  8%  7%
  [libx264 @ 0x68fb900] i8c dc,h,v,p: 52% 15% 26%  7%
  [libx264 @ 0x68fb900] Weighted P-Frames: Y:23.3% UV:21.0%
  [libx264 @ 0x68fb900] ref P L0: 67.4% 15.6% 13.4%  3.5%  0.2%
  [libx264 @ 0x68fb900] ref B L0: 92.2%  6.5%  1.3%
  [libx264 @ 0x68fb900] ref B L1: 98.2%  1.8%
  [libx264 @ 0x68fb900] kb/s:920.11
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-01T06:45:38.040Z
Comments.Text: Why `size=2`? Each input is one image.
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-01T14:40:23.100Z
Comments.Text: Heh thanks. That solved the problem. I got the code from somewhere else!
Comments.UserDisplayName: angel_30
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-01T21:10:11.420Z
Comments.Text: @Gyan do you happen to know what is the license for freezedetect filter? Can we use it from the source code?
Comments.UserDisplayName: angel_30
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-02T04:48:59.847Z
Comments.Text: freezedetect is LGPL 2.1. By source code, do you mean via C API?
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-02T15:00:56.597Z
Comments.Text: @Gyan yes via C API.
Comments.UserDisplayName: angel_30
Tags: <video><ffmpeg><video-editor><encoding>
Title: FFmpeg loop filter doesn't work
UserDisplayName: angel_30
ThreadText: # FFmpeg loop filter doesn't work
  
  (Asked by: username_0 on 2019-04-30)
  
  This is a follow-up from my previous question [here](https://video.stackexchange.com/questions/27498/). Basically, I'm trying to use `FFmpeg`'s loop filter to freeze some frames and insert black frames. It's very weird; I swear it was working a few days ago, but now only the blackframe insertion works, the freezing frames doesn't work. So just no frozen frames inside. I don't know what's going wrong?!
  
  Here is my command. I also updated my ffmpeg to the latest version just now:
  
  ```
  fn="sample.mp4"
  
  #
  ffmpeg -y -i "${fn}" -ss 00:00:05 -to 00:00:06 -r 1/1 _05.png
  ffmpeg -y -i "${fn}" -ss 00:00:10 -to 00:00:11 -r 1/1 _10.png
  ffmpeg -y -i "${fn}" -ss 00:00:15 -to 00:00:16 -r 1/1 _15.png
  ffmpeg -y -i "${fn}" -ss 00:00:20 -to 00:00:21 -r 1/1 _20.png
  ffmpeg -y -i "${fn}" -ss 00:00:25 -to 00:00:26 -r 1/1 _25.png
  ffmpeg -y -i "${fn}" -ss 00:00:30 -to 00:00:31 -r 1/1 _30.png
  ffmpeg -y -i "${fn}" -ss 00:00:35 -to 00:00:36 -r 1/1 _35.png
  
  #
  ffmpeg -y -i "${fn}" \
  -i _05.png \
  -i _10.png \
  -i _15.png \
  -i _20.png \
  -i _25.png \
  -i _30.png \
  -i _35.png \
  -filter_complex "
  [0:v]trim=0:5,setpts=PTS-STARTPTS[0v_1];
  [1:v]loop=loop=25*3:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=2:d=1[pause1];
  [0:v]trim=5:10,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_2];
  [2:v]loop=loop=25*4:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=1[pause2];
  [0:v]trim=10:15,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_3];
  [3:v]loop=loop=25*5:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=2[pause3];
  [0:v]trim=15:20,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_4];
  [4:v]loop=loop=25*6:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=3[pause4];
  [0:v]trim=20:25,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_5];
  [5:v]loop=loop=25*7:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=4[pause5];
  [0:v]trim=25:30,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_6];
  [6:v]loop=loop=25*5:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=3:d=2[pause6];
  [0:v]trim=30:35,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_7];
  [7:v]loop=loop=25*3:size=2
  ,drawtext='fontsize=40:fontcolor=0x0000FF@0.7
  :text=pause -> fade-out':x=920:y=20:shadowcolor=black@0.7:shadowx=1:shadowy=1
  ,fade=t=out:st=2:d=1[pause7];
  [0:v]trim=35,setpts=PTS-STARTPTS
  ,fade=t=in:d=1[0v_8];
  
  [0v_1][pause1]
  [0v_2][pause2]
  [0v_3][pause3]
  [0v_4][pause4]
  [0v_5][pause5]
  [0v_6][pause6]
  [0v_7][pause7]
  [0v_8]
  concat=n=15:a=0:v=1[v]
  " -map '[v]' -an "freeze.mp4"
  
  ```
  
  And here is the whole log (truncating some initial logs for PNG saving due to size limit):
  
  ```
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -> #0:0 (h264 (native) -> png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_25.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.8 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.817x
  video:663kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -> #0:0 (h264 (native) -> png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_30.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.7 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.715x
  video:503kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Stream mapping:
    Stream #0:0 -> #0:0 (h264 (native) -> png (native))
  Press [q] to stop, [?] for help
  Output #0, image2, to '_35.png':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0(und): Video: png, rgb24, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
        encoder         : Lavc58.52.100 png
  frame=    1 fps=0.6 q=-0.0 Lsize=N/A time=00:00:01.00 bitrate=N/A speed=0.637x
  video:539kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  ffmpeg version N-48722-gac551c54b1-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
    libavutil      56. 26.100 / 56. 26.100
    libavcodec     58. 52.100 / 58. 52.100
    libavformat    58. 27.103 / 58. 27.103
    libavdevice    58.  7.100 / 58.  7.100
    libavfilter     7. 50.100 /  7. 50.100
    libswscale      5.  4.100 /  5.  4.100
    libswresample   3.  4.100 /  3.  4.100
    libpostproc    55.  4.100 / 55.  4.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
    Duration: 00:00:45.02, start: 0.000000, bitrate: 1242 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1105 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
      Stream #0:2(eng): Data: none (tmcd / 0x64636D74)
      Metadata:
        handler_name    : VideoHandler
        timecode        : 00:59:55:12
  Input #1, png_pipe, from '_05.png':
    Duration: N/A, bitrate: N/A
      Stream #1:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #2, png_pipe, from '_10.png':
    Duration: N/A, bitrate: N/A
      Stream #2:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #3, png_pipe, from '_15.png':
    Duration: N/A, bitrate: N/A
      Stream #3:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #4, png_pipe, from '_20.png':
    Duration: N/A, bitrate: N/A
      Stream #4:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #5, png_pipe, from '_25.png':
    Duration: N/A, bitrate: N/A
      Stream #5:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #6, png_pipe, from '_30.png':
    Duration: N/A, bitrate: N/A
      Stream #6:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  Input #7, png_pipe, from '_35.png':
    Duration: N/A, bitrate: N/A
      Stream #7:0: Video: png, rgb24(pc), 720x480 [SAR 8:9 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
  [Parsed_drawtext_3 @ 0x6b53ec0] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_9 @ 0x6b5de40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_15 @ 0x6a1a780] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_21 @ 0x6a11940] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_27 @ 0x6b59f40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_33 @ 0x6a12880] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_39 @ 0x698d740] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  Stream mapping:
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #0:0 (h264) -> trim
    Stream #1:0 (png) -> loop
    Stream #2:0 (png) -> loop
    Stream #3:0 (png) -> loop
    Stream #4:0 (png) -> loop
    Stream #5:0 (png) -> loop
    Stream #6:0 (png) -> loop
    Stream #7:0 (png) -> loop
    concat -> Stream #0:0 (libx264)
  Press [q] to stop, [?] for help
  [Parsed_drawtext_3 @ 0x6f3e480] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_9 @ 0x6f4ec00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_15 @ 0x6f57e00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_21 @ 0x6f65600] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_27 @ 0x6f6ed00] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_33 @ 0x6f79c40] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [Parsed_drawtext_39 @ 0x6f84dc0] Using "/usr/share/fonts/dejavu/DejaVuSans.ttf"
  [libx264 @ 0x68fb900] using SAR=8/9
  [libx264 @ 0x68fb900] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
  [libx264 @ 0x68fb900] profile Progressive High, level 3.0, 4:2:0, 8-bit
  [libx264 @ 0x68fb900] 264 - core 157 r2969 d4099dd - H.264/MPEG-4 AVC codec - Copyleft 2003-2019 - http://www.videolan.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 lookahead_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_lookahead=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 'freeze.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf58.27.103
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc (default)
      Metadata:
        encoder         : Lavc58.52.100 libx264
      Side data:
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  frame= 1351 fps= 75 q=-1.0 Lsize=    5080kB time=00:00:44.97 bitrate= 925.2kbits/s dup=0 drop=5 speed=2.49x
  video:5064kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.321138%
  [libx264 @ 0x68fb900] frame I:19    Avg QP:18.75  size: 30579
  [libx264 @ 0x68fb900] frame P:424   Avg QP:22.86  size:  7793
  [libx264 @ 0x68fb900] frame B:908   Avg QP:26.77  size:  1431
  [libx264 @ 0x68fb900] consecutive B-frames:  5.8% 11.5%  6.2% 76.4%
  [libx264 @ 0x68fb900] mb I  I16..4: 11.1% 63.3% 25.6%
  [libx264 @ 0x68fb900] mb P  I16..4:  1.6%  6.2%  1.0%  P16..4: 45.2% 16.3%  8.6%  0.0%  0.0%    skip:21.0%
  [libx264 @ 0x68fb900] mb B  I16..4:  0.3%  0.5%  0.1%  B16..8: 33.2%  3.4%  0.6%  direct: 1.3%  skip:60.6%  L0:47.5% L1:46.2% BI: 6.3%
  [libx264 @ 0x68fb900] 8x8 transform intra:66.7% inter:72.0%
  [libx264 @ 0x68fb900] coded y,uvDC,uvAC intra: 52.5% 70.2% 34.8% inter: 11.4% 19.5% 0.9%
  [libx264 @ 0x68fb900] i16 v,h,dc,p: 55% 14% 10% 22%
  [libx264 @ 0x68fb900] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28% 13% 22%  5%  6%  8%  6%  7%  5%
  [libx264 @ 0x68fb900] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 23% 14% 12%  7% 10% 10%  8%  8%  7%
  [libx264 @ 0x68fb900] i8c dc,h,v,p: 52% 15% 26%  7%
  [libx264 @ 0x68fb900] Weighted P-Frames: Y:23.3% UV:21.0%
  [libx264 @ 0x68fb900] ref P L0: 67.4% 15.6% 13.4%  3.5%  0.2%
  [libx264 @ 0x68fb900] ref B L0: 92.2%  6.5%  1.3%
  [libx264 @ 0x68fb900] ref B L1: 98.2%  1.8%
  [libx264 @ 0x68fb900] kb/s:920.11
  
  ```
  
  **Tags:** video, ffmpeg, video-editor, encoding
  
  > **Comments:**
  > **username_1**: Why `size=2`? Each input is one image.  
  > **username_0**: Heh thanks. That solved the problem. I got the code from somewhere else!  
  > **username_0**: @username_1 do you happen to know what is the license for freezedetect filter? Can we use it from the source code?  
  > **username_1**: freezedetect is LGPL 2.1. By source code, do you mean via C API?  
  > **username_0**: @username_1 yes via C API.  
  
  ---
  
  ## 0 answers
  
  