Body: <p>I'm using ffmpeg over 3 years now mainly I'm doing live broadcasting on my site , currently I'm preparing to do 5 livebroadcast on the same time using my VPS server <code>CPU E3-1240 v5</code> <code>OpenVZ</code> Since I'm only allowed to use 1 vCore CPU usage jumps high very fast . What I ask , I know H264 algorithm based on calculation of previous frame (ref frame) and I frame So I tried -copyinkf and -break_non_keyframes 1 with no effect on the speed BTW here is my main broadcast command :-</p>
  
  <pre><code>ffmpeg -re -i "http://sorce.m3u " -s 720x406 -r 23.976 -vcodec libx264  -profile:v high444  \ 
  -crf 35 -copyinkf - break_non_keyframes 1 -preset slow -acodec libfdk_aac \
  -profile:a aac_he_v2 -b:a 8k -map_metadata -1 -f flv rtmp://localhost/hls/live 
  </code></pre>
  
  <p>Current I use <code>-preset slow</code> to improve image quality little bit CPU usage <code>60%</code> even with <code>preset fast</code> CPU usage were <code>47%</code> -preset veryfast CPU-usage <code>35%</code></p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-01-29T19:15:51.577Z
Comments.Text: What's wrong with the faster presets?
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-01-29T22:04:43.443Z
Comments.Text: it's peak the CPU usage sometime goes up `50%` which will kill the tow process , and their is huge quality drop, this setting is the lowest I can get for ~`265kbps`broadcast ,,+ I test it without the extra `-copyinkf` flags with no different at all , BTW I'm using `crf` method with value of  `35`
Comments.UserDisplayName: Salem F
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-01-30T17:06:34.933Z
Comments.Text: There is no way to use less CPU without reducing quality. If there was, that setting would be turned on by default.
Comments.UserDisplayName: SlimSCSI
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-01-30T18:23:30.403Z
Comments.Text: I'm using low pic size `720x406` with low bitrate , on my laptop cpu its run it fast , but the server VPS limited to 1 vCore so my code above will uses more cpu resources .
Comments.UserDisplayName: Salem F
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-01-30T20:05:09.180Z
Comments.Text: Alright I found out what's was peak CPU usage `-profile:v high444` once I remove it the cpu usage drooped dramatically to less  then `30%`
Comments.UserDisplayName: Salem F
Tags: <ffmpeg><h.264><rtmp>
Title: Reduce CPU usage when downscaling HD>SD>Low on the same codec (H264)
UserDisplayName: Salem F
ThreadText: # Reduce CPU usage when downscaling HD>SD>Low on the same codec (H264)
  
  (Asked by: username_0 on 2019-01-29)
  
  I'm using ffmpeg over 3 years now mainly I'm doing live broadcasting on my site , currently I'm preparing to do 5 livebroadcast on the same time using my VPS server `CPU E3-1240 v5` `OpenVZ` Since I'm only allowed to use 1 vCore CPU usage jumps high very fast . What I ask , I know H264 algorithm based on calculation of previous frame (ref frame) and I frame So I tried -copyinkf and -break\_non\_keyframes 1 with no effect on the speed BTW here is my main broadcast command :-
  
  ```
  ffmpeg -re -i "http://sorce.m3u " -s 720x406 -r 23.976 -vcodec libx264  -profile:v high444  \ 
  -crf 35 -copyinkf - break_non_keyframes 1 -preset slow -acodec libfdk_aac \
  -profile:a aac_he_v2 -b:a 8k -map_metadata -1 -f flv rtmp://localhost/hls/live 
  
  ```
  
  Current I use `-preset slow` to improve image quality little bit CPU usage `60%` even with `preset fast` CPU usage were `47%` -preset veryfast CPU-usage `35%`
  
  **Tags:** ffmpeg, h.264, rtmp
  
  > **Comments:**
  > **username_1**: What's wrong with the faster presets?  
  > **username_0**: it's peak the CPU usage sometime goes up `50%` which will kill the tow process , and their is huge quality drop, this setting is the lowest I can get for ~`265kbps`broadcast ,,+ I test it without the extra `-copyinkf` flags with no different at all , BTW I'm using `crf` method with value of  `35`  
  > **username_2**: There is no way to use less CPU without reducing quality. If there was, that setting would be turned on by default.  
  > **username_0**: I'm using low pic size `720x406` with low bitrate , on my laptop cpu its run it fast , but the server VPS limited to 1 vCore so my code above will uses more cpu resources .  
  > **username_0**: Alright I found out what's was peak CPU usage `-profile:v high444` once I remove it the cpu usage drooped dramatically to less  then `30%`  
  
  ---
  
  ## 0 answers
  
  