Answers.Body: <p>Use the <a href="http://www.ffmpeg.org/ffmpeg-filters.html#setparams-1" rel="nofollow noreferrer">setparams</a> filter to mark the frames as interlaced.</p>
  <pre><code>ffmpeg -i tf.avi -i bf.avi -filter_complex vstack,il=l=i:c=i,setparams=field_mode=tff -c:v ffv1 out_i.avi
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-02-23T05:06:19.047Z
Answers.Text: Thank you very much Now, my NLE detects it as interlaced, at least when switching to a well supported codec, Prores. However, ffprobe shows 'top coded first (swapped)', instead of  'top first' and, tbn and tbc show 12800 (default), instead of 50. Not clear if this has any negative impact. I assume I have to create a new thread on this?
Answers.UserDisplayName: The Lightworker
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-02-23T04:10:22.667Z
Answers.LastActivityDate: 2021-02-23T04:10:22.667Z
Answers.UserDisplayName: Gyan
Body: <p>I'm having trouble with the command found here: <a href="https://video.stackexchange.com/questions/27524/combining-two-video-fields-into-one-to-create-an-interlaced-video">Combining two video fields into one (to create an interlaced video)</a></p>
  <p><code>ffmpeg -i tf.avi -i bf.avi -filter_complex vstack,il=l=i:c=i -c:v ffv1 out_i.avi</code></p>
  <p>It seems to combine the fields correctly, the output, however, appears to be progressive. To test, I used
  the video 'in_i.mxf' (XCDCAM HD 422, 1080i25) and separated the fields in tf.avi and bf.avi, using this:</p>
  <p><code>ffmpeg -i in_i.mxf -vf field=top -c:v ffv1 -an tf.avi -vf field=bottom -c:v ffv1 -an bf.avi</code></p>
  <p>That's the result of 'ffmpeg -i in_i.mxf -i tf.avi -i bf.avi -i out_i.avi':</p>
  <pre><code>Input #0, mxf, from 'in_i.mxf':
    Metadata:
      operational_pattern_ul: 060e2b34.04010101.0d010201.01010900
      uid             : 25e9aa02-7405-4800-809e-0700022483ea
      generation_uid  : 25e9aa02-7405-4800-811e-0700022483ea
      company_name    : CANON
      product_name    : XF105
      product_version : 1.00
      product_uid     : 060e2b34-0401-010d-0e15-005658460100
      modification_date: 2016-01-15T14:48:13.000000Z
      material_package_umid: 0x060A2B340101010501010D43130000000A25E9AB0274058000008500022483EA
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 51874 kb/s  
    Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
    Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
      Side data:          cpb: bitrate max/min/avg: 50000000/0/0 buffer size: 17825792 vbv_delay: N/A
  Stream #0:1: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
  Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
  Stream #0:2: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
  Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
  
  Input #1, avi, from 'tf.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 98506 kb/s
    Stream #1:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x540, 98889 kb/s, SAR 1:1 DAR 32:9, 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  Input #2, avi, from 'bf.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 98381 kb/s
    Stream #2:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x540, 98763 kb/s, SAR 1:1 DAR 32:9, 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  Input #3, avi, from 'out_i.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 201187 kb/s
    Stream #3:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x1080, 201979 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 25 tbn, 25 tbc          
  </code></pre>
  <p>It might be just a metadata problem? Any ideas how to optimize?</p>
  
Tags: <ffmpeg>
Title: Trouble When Combining two video fields into one (to create an interlaced video)
UserDisplayName: The Lightworker
ThreadText: # Trouble When Combining two video fields into one (to create an interlaced video)
  
  (Asked by: username_0 on 2021-02-23)
  
  I'm having trouble with the command found here: [Combining two video fields into one (to create an interlaced video)](https://video.stackexchange.com/questions/27524/combining-two-video-fields-into-one-to-create-an-interlaced-video)
  
  `ffmpeg -i tf.avi -i bf.avi -filter_complex vstack,il=l=i:c=i -c:v ffv1 out_i.avi`
  
  It seems to combine the fields correctly, the output, however, appears to be progressive. To test, I used
  the video 'in\_i.mxf' (XCDCAM HD 422, 1080i25) and separated the fields in tf.avi and bf.avi, using this:
  
  `ffmpeg -i in_i.mxf -vf field=top -c:v ffv1 -an tf.avi -vf field=bottom -c:v ffv1 -an bf.avi`
  
  That's the result of 'ffmpeg -i in\_i.mxf -i tf.avi -i bf.avi -i out\_i.avi':
  
  ```
  Input #0, mxf, from 'in_i.mxf':
    Metadata:
      operational_pattern_ul: 060e2b34.04010101.0d010201.01010900
      uid             : 25e9aa02-7405-4800-809e-0700022483ea
      generation_uid  : 25e9aa02-7405-4800-811e-0700022483ea
      company_name    : CANON
      product_name    : XF105
      product_version : 1.00
      product_uid     : 060e2b34-0401-010d-0e15-005658460100
      modification_date: 2016-01-15T14:48:13.000000Z
      material_package_umid: 0x060A2B340101010501010D43130000000A25E9AB0274058000008500022483EA
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 51874 kb/s  
    Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 50000 kb/s, 25 fps, 25 tbr, 25 tbn, 50 tbc
    Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
      Side data:          cpb: bitrate max/min/avg: 50000000/0/0 buffer size: 17825792 vbv_delay: N/A
  Stream #0:1: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
  Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
  Stream #0:2: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
  Metadata:
    file_package_umid: 0x060A2B340101010501010D43130000000A25E9AA0274058000008500022483EA
  
  Input #1, avi, from 'tf.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 98506 kb/s
    Stream #1:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x540, 98889 kb/s, SAR 1:1 DAR 32:9, 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  Input #2, avi, from 'bf.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 98381 kb/s
    Stream #2:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x540, 98763 kb/s, SAR 1:1 DAR 32:9, 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  Input #3, avi, from 'out_i.avi':
    Metadata:
      software        : Lavf58.67.100
      timecode        : 13:13:46:14
    Duration: 00:00:10.08, start: 0.000000, bitrate: 201187 kb/s
    Stream #3:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p, 1920x1080, 201979 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 25 tbn, 25 tbc          
  
  ```
  
  It might be just a metadata problem? Any ideas how to optimize?
  
  **Tags:** ffmpeg
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2021-02-23. Score: 1
  
  Use the [setparams](http://www.ffmpeg.org/ffmpeg-filters.html#setparams-1) filter to mark the frames as interlaced.
  
  ```
  ffmpeg -i tf.avi -i bf.avi -filter_complex vstack,il=l=i:c=i,setparams=field_mode=tff -c:v ffv1 out_i.avi
  
  ```
  
  > **Comments:**
  > **username_0**: Thank you very much Now, my NLE detects it as interlaced, at least when switching to a well supported codec, Prores. However, ffprobe shows 'top coded first (swapped)', instead of  'top first' and, tbn and tbc show 12800 (default), instead of 50. Not clear if this has any negative impact. I assume I have to create a new thread on this?  
  
  ---
  
  