Answers.Body: <p>ffmpeg's <code>libx265</code> wrapper is very minimal, and doesn't pass on very many settings.  e.g. <code>-pass 1</code> requires manually setting <code>-x265-params pass=1</code>.</p>
  
  <p>Also, if x265 is anything like x264, don't use ultrafast except for lossless or for testing things.</p>
  
  <p>sorry for not taking the time to dig this up myself, but have a look and see if you can get your desired I frame locations into x265-params.  Probably not, though.</p>
  
  <p>If you want to hack some C code, have a look at <code>libx264.c</code> and <code>libx265.c</code>, and maybe you can see how to ffmpeg sends frame-type requests to x264.  And maybe you can port that to the libx265 wrapper.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2015-02-25T04:42:49.893Z
Answers.LastActivityDate: 2015-02-25T04:42:49.893Z
Answers.UserDisplayName: Peter Cordes
Body: <p>I'm trying encode a video stream using HEVC with ffmpeg and create a MPEG-TS file. I need to be able to insert IDR frames to certain locations in the stream. I came across the flag <code>-force_key_frames</code> under ffmpeg documentation, but it doesn't seem to work for me. </p>
  
  <p>Here is the command I tried:</p>
  
  <p><code>ffmpeg -s:v 1280x720 -i input.yuv -c:v libx265 -x265-params crf=20:keyint=25:fps=25:preset=ultrafast -force_key_frames 1,12,30,111 -f mpegts out.ts</code></p>
  
  <p>Please help me to sort out this issue.</p>
  
  <p>Thanks.</p>
  
Tags: <ffmpeg><transcoding>
Title: using -force_key_frames in ffmpeg with libx265
UserDisplayName: userDtrm
ThreadText: # using -force_key_frames in ffmpeg with libx265
  
  (Asked by: username_0 on 2015-02-24)
  
  I'm trying encode a video stream using HEVC with ffmpeg and create a MPEG-TS file. I need to be able to insert IDR frames to certain locations in the stream. I came across the flag `-force_key_frames` under ffmpeg documentation, but it doesn't seem to work for me.
  
  Here is the command I tried:
  
  `ffmpeg -s:v 1280x720 -i input.yuv -c:v libx265 -x265-params crf=20:keyint=25:fps=25:preset=ultrafast -force_key_frames 1,12,30,111 -f mpegts out.ts`
  
  Please help me to sort out this issue.
  
  Thanks.
  
  **Tags:** ffmpeg, transcoding
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2015-02-25. Score: 1
  
  ffmpeg's `libx265` wrapper is very minimal, and doesn't pass on very many settings. e.g. `-pass 1` requires manually setting `-x265-params pass=1`.
  
  Also, if x265 is anything like x264, don't use ultrafast except for lossless or for testing things.
  
  sorry for not taking the time to dig this up myself, but have a look and see if you can get your desired I frame locations into x265-params. Probably not, though.
  
  If you want to hack some C code, have a look at `libx264.c` and `libx265.c`, and maybe you can see how to ffmpeg sends frame-type requests to x264. And maybe you can port that to the libx265 wrapper.
  
  
  ---
  
  