Answers.Body: <p>You can use ffmpeg (and grep) to do this.</p>
  <p>Run</p>
  <p><code>ffmpeg -i H264file -c copy -bsf:v trace_headers -f null - 2&gt;&amp;1 | grep first_mb_in_slice</code></p>
  <p>This should print out lines of the form</p>
  <pre><code>[trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice                     1 = 0
  [trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice     00000000101000001 = 320
  [trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice   0000000001010000001 = 640
  </code></pre>
  <p>If each frame is a single slice then ALL lines will have value 0 (<code>1 = 0</code>) for <code>first_mb_in_slice</code>. A non-zero value indicates sliced encoding.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-04-13T06:11:49.173Z
Answers.Text: Thank you. This is helpful and does workout.
Answers.UserDisplayName: Bivas
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-04-12T04:50:29.193Z
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Body: <p>I'm a software tester and I need to test a certain requirement for a vehicle camera that I'm not sure on how to test.
  As in the title it's to verify that each frame is encoded with a single slice. This is done for more efficient encoding.</p>
  <p>AVTP/h264, configured with high profile, to have only I-frames, progressively encoded.</p>
  <p>I'm not that knowledgeable with imaging and video streaming, so any help would be appreciated.</p>
  
Tags: <ffmpeg><encoding><video-quality><streaming><h.264>
Title: How do I verify that the H264 video stream is encoded with a single slice per frame?
UserDisplayName: Bivas
ThreadText: # How do I verify that the H264 video stream is encoded with a single slice per frame?
  
  (Asked by: username_0 on 2022-04-11)
  
  I'm a software tester and I need to test a certain requirement for a vehicle camera that I'm not sure on how to test.
  As in the title it's to verify that each frame is encoded with a single slice. This is done for more efficient encoding.
  
  AVTP/h264, configured with high profile, to have only I-frames, progressively encoded.
  
  I'm not that knowledgeable with imaging and video streaming, so any help would be appreciated.
  
  **Tags:** ffmpeg, encoding, video-quality, streaming, h.264
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2022-04-12. Score: 0 | Accepted answer
  
  You can use ffmpeg (and grep) to do this.
  
  Run
  
  `ffmpeg -i H264file -c copy -bsf:v trace_headers -f null - 2>&1 | grep first_mb_in_slice`
  
  This should print out lines of the form
  
  ```
  [trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice                     1 = 0
  [trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice     00000000101000001 = 320
  [trace_headers @ 000002087b24c3c0] 8   first_mb_in_slice   0000000001010000001 = 640
  
  ```
  
  If each frame is a single slice then ALL lines will have value 0 (`1 = 0`) for `first_mb_in_slice`. A non-zero value indicates sliced encoding.
  
  > **Comments:**
  > **username_0**: Thank you. This is helpful and does workout.  
  
  ---
  
  