Answers.Body: <p>Two ways:</p>
  
  <p><strong>#1</strong> By specifying gdigrab options:</p>
  
  <pre><code>ffmpeg -f gdigrab -framerate 24 -video_size 960x540 -offset_x 240 -offset_y 450 -i desktop -preset ultrafast -pix_fmt yuv420p out.mp4
  </code></pre>
  
  <p>This captures a 960x540 video whose top-left corner is at (240,450) measured from the top-left corner of the display.</p>
  
  <p><strong>#2</strong> By cropping it post-capture</p>
  
  <pre><code>ffmpeg -f gdigrab -framerate 24 -i desktop -vf crop=960:540:240:450 -preset ultrafast -pix_fmt yuv420p out.mp4
  </code></pre>
  
  <p>The former is preferable.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-07-28T05:01:25.583Z
Answers.LastActivityDate: 2017-07-28T05:01:25.583Z
Answers.UserDisplayName: Gyan
Body: <p>I'm using this line to record from the desktop to a video file:</p>
  
  <pre><code>ffmpeg -f gdigrab -framerate 24 -i desktop -preset ultrafast -pix_fmt yuv420p out.mp4
  </code></pre>
  
  <p>But this will record the whole desktop.
  Is there any way to record in real time only specific area/part of the desktop ?</p>
  
Tags: <ffmpeg>
Title: How can i crop part of a video while recording from desktop in real time using ffmpeg?
UserDisplayName: Hanan
ThreadText: # How can i crop part of a video while recording from desktop in real time using ffmpeg?
  
  (Asked by: username_0 on 2017-07-27)
  
  I'm using this line to record from the desktop to a video file:
  
  ```
  ffmpeg -f gdigrab -framerate 24 -i desktop -preset ultrafast -pix_fmt yuv420p out.mp4
  
  ```
  
  But this will record the whole desktop.
  Is there any way to record in real time only specific area/part of the desktop ?
  
  **Tags:** ffmpeg
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2017-07-28. Score: 2
  
  Two ways:
  
  **#1** By specifying gdigrab options:
  
  ```
  ffmpeg -f gdigrab -framerate 24 -video_size 960x540 -offset_x 240 -offset_y 450 -i desktop -preset ultrafast -pix_fmt yuv420p out.mp4
  
  ```
  
  This captures a 960x540 video whose top-left corner is at (240,450) measured from the top-left corner of the display.
  
  **#2** By cropping it post-capture
  
  ```
  ffmpeg -f gdigrab -framerate 24 -i desktop -vf crop=960:540:240:450 -preset ultrafast -pix_fmt yuv420p out.mp4
  
  ```
  
  The former is preferable.
  
  
  ---
  
  