Answers.Body: <p>Add <code>-r 25</code> to your command.</p>
  
  <p>The <code>q</code> readout refers to the allowed range for the quantizer. There's no bounds applied in your command, but you can limit by setting one or both of </p>
  
  <p><code>-qmin N</code> and <code>-qmax N</code></p>
  
  <p>Unless you have good reason to, don't change it.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-07-18T12:03:53.290Z
Answers.Text: How would this set the `tbc` to 50? I have exactly the same problem, I need to set `tbc` to 25 while keeping `fps` to 50
Answers.UserDisplayName: etuardu
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-07-18T13:11:37.730Z
Answers.Text: That's the opposite problem: tbc of 25 and fps of 50. `-r` will set the framerate and libx264 sets its time base (tbc) to twice that.
Answers.UserDisplayName: Gyan
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-01-22T12:54:09.893Z
Answers.LastActivityDate: 2016-01-22T12:54:09.893Z
Answers.UserDisplayName: Gyan
Answers.Body: <p>You can accomplish that by adding <code>-r 25</code> or even <code>-r 60</code>, as you like to experiment. Here's example:</p>
  
  <pre><code> ffmpeg -r 25 -i input.mov codec:v copy codec:a copy -f mp4 output.mp4
  </code></pre>
  
  <p>instead of</p>
  
  <pre><code>ffmpeg -i input.mov codec:v copy -r 25 codec:a copy -f mp4 output.mp4
  </code></pre>
  
  <p>The key I found to be in control exactly what I wanted is to place <code>-r 25</code> right before the input agrument.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-24T06:52:21.167Z
Answers.Text: When streamcopying, this only works for raw video streams.
Answers.UserDisplayName: Gyan
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-24T05:55:54.357Z
Answers.LastActivityDate: 2016-08-25T14:59:38.497Z
Answers.LastEditDate: 2016-08-25T14:59:38.497Z
Answers.UserDisplayName: Faron
Body: <p>I need to set tbc option for output video. For example, input video has 25 fps with 50 tbc and my encoded video has 25fps with 25 tbc. I used settb and video_track_timescale but these options did not change tbc. So my question is how can i set double fps for tbc?</p>
  
  <p>Input video log</p>
  
  <blockquote>
  <pre><code>Duration: 00:04:41.33, start: 0.000000, bitrate: 1258 kb/s Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1064 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc (default)
  </code></pre>
  </blockquote>
  
  <p>Output video log</p>
  
  <blockquote>
  <pre><code>Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 
      [SAR 1:1 DAR 16:9], q=-1--1, max. 1835 kb/s, 25 fps, 12800 tbn, 25 tbc (default)
  </code></pre>
  </blockquote>
  
  <p>The ffmpeg command</p>
  
  <pre><code>ffmpeg -y -i input.mp4 -filter_complex "scale=-2:'min(720,ih)',fps=25" -codec:v libx264 
      -profile:v high -level 4.0 -preset slow -minrate 1835k -maxrate 1835k -bufsize 2441k
      -c:a aac -strict experimental -q:a 9 -crf 20 -pix_fmt yuv420p 
      output.mp4 1&gt; output.log 2&gt;&amp;1
  </code></pre>
  
  <p>Full output log</p>
  
  <pre><code>ffmpeg version N-76684-g1fe82ab Copyright (c) 2000-2015 the FFmpeg developers     
  built with gcc 5.2.0 (GCC)  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib  
    libavutil      55.  6.100 / 55.  6.100
    libavcodec     57. 15.100 / 57. 15.100
    libavformat    57. 14.100 / 57. 14.100
    libavdevice    57.  0.100 / 57.  0.100
    libavfilter     6. 15.100 /  6. 15.100
    libswscale      4.  0.100 /  4.  0.100
    libswresample   2.  0.101 /  2.  0.101
    libpostproc    54.  0.100 / 54.  0.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
    Metadata:
      major_brand     : mp42
      minor_version   : 0
      compatible_brands: isommp42
      creation_time   : 2015-02-20 11:51:25
    Duration: 00:04:41.33, start: 0.000000, bitrate: 1258 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1064 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc (default)
      Metadata:
        creation_time   : 1970-01-01 00:00:00
        handler_name    : VideoHandler
      Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 192 kb/s (default)
      Metadata:
        creation_time   : 2015-02-20 11:51:26
        handler_name    : IsoMedia File Produced by Google, 5-11-2011
  [libx264 @ 0000001d2ffe0a00] using SAR=1/1
  [libx264 @ 0000001d2ffe0a00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  [libx264 @ 0000001d2ffe0a00] profile High, level 4.0
  [libx264 @ 0000001d2ffe0a00] 264 - core 148 r2638 7599210 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=5 deblock=1:0:0 analyse=0x3:0x113 me=umh subme=8 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=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=crf mbtree=1 crf=20.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=1835 vbv_bufsize=2441 crf_max=0.0 nal_hrd=none filler=0 ip_ratio=1.40 aq=1:1.00
  Output #0, mp4, to 'output.mp4':
    Metadata:
      major_brand     : mp42
      minor_version   : 0
      compatible_brands: isommp42
      encoder         : Lavf57.14.100
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, max. 1835 kb/s, 25 fps, 12800 tbn, 25 tbc (default)
      Metadata:
        encoder         : Lavc57.15.100 libx264
      Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        creation_time   : 2015-02-20 11:51:26
        handler_name    : IsoMedia File Produced by Google, 5-11-2011
        encoder         : Lavc57.15.100 aac
  Stream mapping:
    Stream #0:0 (h264) -&gt; scale (graph 0)
    settb (graph 0) -&gt; Stream #0:0 (libx264)
    Stream #0:1 -&gt; #0:1 (aac (native) -&gt; aac (native))
  Press [q] to stop, [?] for help
  frame=    3 fps=0.0 q=0.0 size=       0kB time=00:00:05.89 bitrate=   0.1kbits/s dup=0 drop=148
  </code></pre>
  
  <p>Also in output video, i see option <strong>q=-1--1</strong>. What is this? How can i configure this option?</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-03-22T17:56:00.197Z
Comments.Text: Is this to create 25 PsF streams or what is the purpose of the operation?
Comments.UserDisplayName: Hans Meiser
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-03-25T11:40:47.700Z
Comments.Text: @HansMeiser No, i just wanted to set double tbc from fps. Now i understood that there is no neccessary to change this option.
Comments.UserDisplayName: nurmat
Tags: <ffmpeg><conversion><h.264>
Title: How to set double fps for tbc option of video
UserDisplayName: nurmat
ThreadText: # How to set double fps for tbc option of video
  
  (Asked by: username_0 on 2016-01-22)
  
  I need to set tbc option for output video. For example, input video has 25 fps with 50 tbc and my encoded video has 25fps with 25 tbc. I used settb and video\_track\_timescale but these options did not change tbc. So my question is how can i set double fps for tbc?
  
  Input video log
  
  > ```
  > Duration: 00:04:41.33, start: 0.000000, bitrate: 1258 kb/s Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1064 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc (default)
  >
  > ```
  
  Output video log
  
  > ```
  > Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 
  >     [SAR 1:1 DAR 16:9], q=-1--1, max. 1835 kb/s, 25 fps, 12800 tbn, 25 tbc (default)
  >
  > ```
  
  The ffmpeg command
  
  ```
  ffmpeg -y -i input.mp4 -filter_complex "scale=-2:'min(720,ih)',fps=25" -codec:v libx264 
      -profile:v high -level 4.0 -preset slow -minrate 1835k -maxrate 1835k -bufsize 2441k
      -c:a aac -strict experimental -q:a 9 -crf 20 -pix_fmt yuv420p 
      output.mp4 1> output.log 2>&1
  
  ```
  
  Full output log
  
  ```
  ffmpeg version N-76684-g1fe82ab Copyright (c) 2000-2015 the FFmpeg developers     
  built with gcc 5.2.0 (GCC)  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib  
    libavutil      55.  6.100 / 55.  6.100
    libavcodec     57. 15.100 / 57. 15.100
    libavformat    57. 14.100 / 57. 14.100
    libavdevice    57.  0.100 / 57.  0.100
    libavfilter     6. 15.100 /  6. 15.100
    libswscale      4.  0.100 /  4.  0.100
    libswresample   2.  0.101 /  2.  0.101
    libpostproc    54.  0.100 / 54.  0.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
    Metadata:
      major_brand     : mp42
      minor_version   : 0
      compatible_brands: isommp42
      creation_time   : 2015-02-20 11:51:25
    Duration: 00:04:41.33, start: 0.000000, bitrate: 1258 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 1064 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc (default)
      Metadata:
        creation_time   : 1970-01-01 00:00:00
        handler_name    : VideoHandler
      Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 192 kb/s (default)
      Metadata:
        creation_time   : 2015-02-20 11:51:26
        handler_name    : IsoMedia File Produced by Google, 5-11-2011
  [libx264 @ 0000001d2ffe0a00] using SAR=1/1
  [libx264 @ 0000001d2ffe0a00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  [libx264 @ 0000001d2ffe0a00] profile High, level 4.0
  [libx264 @ 0000001d2ffe0a00] 264 - core 148 r2638 7599210 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=5 deblock=1:0:0 analyse=0x3:0x113 me=umh subme=8 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=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=crf mbtree=1 crf=20.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=1835 vbv_bufsize=2441 crf_max=0.0 nal_hrd=none filler=0 ip_ratio=1.40 aq=1:1.00
  Output #0, mp4, to 'output.mp4':
    Metadata:
      major_brand     : mp42
      minor_version   : 0
      compatible_brands: isommp42
      encoder         : Lavf57.14.100
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, max. 1835 kb/s, 25 fps, 12800 tbn, 25 tbc (default)
      Metadata:
        encoder         : Lavc57.15.100 libx264
      Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 128 kb/s (default)
      Metadata:
        creation_time   : 2015-02-20 11:51:26
        handler_name    : IsoMedia File Produced by Google, 5-11-2011
        encoder         : Lavc57.15.100 aac
  Stream mapping:
    Stream #0:0 (h264) -> scale (graph 0)
    settb (graph 0) -> Stream #0:0 (libx264)
    Stream #0:1 -> #0:1 (aac (native) -> aac (native))
  Press [q] to stop, [?] for help
  frame=    3 fps=0.0 q=0.0 size=       0kB time=00:00:05.89 bitrate=   0.1kbits/s dup=0 drop=148
  
  ```
  
  Also in output video, i see option **q=-1--1**. What is this? How can i configure this option?
  
  **Tags:** ffmpeg, conversion, h.264
  
  > **Comments:**
  > **username_1**: Is this to create 25 PsF streams or what is the purpose of the operation?  
  > **username_0**: @username_1 No, i just wanted to set double tbc from fps. Now i understood that there is no neccessary to change this option.  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_2 on 2016-01-22. Score: 1
  
  Add `-r 25` to your command.
  
  The `q` readout refers to the allowed range for the quantizer. There's no bounds applied in your command, but you can limit by setting one or both of
  
  `-qmin N` and `-qmax N`
  
  Unless you have good reason to, don't change it.
  
  > **Comments:**
  > **username_3**: How would this set the `tbc` to 50? I have exactly the same problem, I need to set `tbc` to 25 while keeping `fps` to 50  
  > **username_2**: That's the opposite problem: tbc of 25 and fps of 50. `-r` will set the framerate and libx264 sets its time base (tbc) to twice that.  
  
  ---
  
  ### Answer by username_4 on 2016-08-24. Score: 0
  
  You can accomplish that by adding `-r 25` or even `-r 60`, as you like to experiment. Here's example:
  
  ```
   ffmpeg -r 25 -i input.mov codec:v copy codec:a copy -f mp4 output.mp4
  
  ```
  
  instead of
  
  ```
  ffmpeg -i input.mov codec:v copy -r 25 codec:a copy -f mp4 output.mp4
  
  ```
  
  The key I found to be in control exactly what I wanted is to place `-r 25` right before the input agrument.
  
  > **Comments:**
  > **username_2**: When streamcopying, this only works for raw video streams.  
  
  ---
  
  