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• How to stream live h.264 (IP camera) video to browser ? (bonus : low bandwidth and latency)

  4 octobre 2018, par Ryan Griggs

  I need to stream live h.264-encoded video from an IP camera to the browser, while supporting all common browsers and mobile devices (i.e. Android, Firefox, Chrome, IE, Safari (Mac OS and iOS)), and while keeping bandwidth requirements and latency to a minimum.

  MPEG-DASH requires browser support for Media Source Extensions, which are NOT supported by iOS. So that’s out.

  HLS is only supported by Safari and Edge.

  Also DASH seems to impose a latency of several seconds, which is not preferable.

  I would like to be able to chunk the incoming h.264 data (i.e. fragmented MP4), pass the chunked data to the browser via Websockets, then dump the chunks into some sort of player as they arrive.

  Broadway and its forks are a javascript h.264 decoder, and there is a Broadway-stream project that supports streams instead of files, but the docs are poor and I can only find examples of streaming when the source is not live.

  The most pressing question is : how do I hand the "chunked data" to a player or Video HTML element as it arrives at the browser ?

  I think the ideal setup would be to

  1. Use ffmpeg to transcode the original video to a chunked format (fMP4)
  2. Pipe the chunked output to a Node JS app which emits each chunk out through a Websocket to all connected viewers
  3. Viewers’ browsers dump each incoming chunk into some sort of decoder which renders the video.

  I’m clear up to the point of handing the received chunks to a video decoder. How can that be done without depending on Media Source Extensions, and allowing viewers to join the stream at random times ?

• In FFmpeg, using -filter_complex, how can I overlay and blend at the same time ?

  20 avril 2023, par Kristian Boruff

  My code works to combine three videos, resize the videos to 1920X1080, resize the watermark to the correct size, and then overlays the watermark to the lower left hand side. Then converts to the intended codecs for Youtube.
My question is how do I Blend at the same time using the -filter_complex workflow ?
Currently, I have the following workflow that does everything but set the opacity

  



  ffmpeg -y -i fancy movie.mov -i logo.png -i in.mov -i out.mov -c:v libx264 -crf 18 -b:v 50000k -preset veryfast -tune film -profile:v high -x264opts cabac=1:keyint=16:bframes=2:keyint_min=15 -c:a libvo_aacenc -ab 128K -ar 48000 -filter_complex "[0:0] scale=1920X1080 [main]; [2:0] scale=1920X1080 [start]; [3:0] scale=1920X1080 [end]; [start] [2:1] [main] [0:1] [end] [3:1] concat=n=3:v=1:a=1 [prog]; [1:0] scale=480:90 [wm]; [prog] [wm] overlay=36:main_h-overlay_h-45" fart.mp4


  



  I'm trying to add "blend=all_opacity=0.7" in the last step so the watermark will screen against the background. If I just add

  



  [prog] [wm] overlay=36:main_h-overlay_h-45, blend=all_mode='overlay':all_opacity=0.7" fart.mp4


  



  I get the error, Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_blend_6

  



  If I try a semicolon instead,

  



  [prog] [wm] overlay=36:main_h-overlay_h-45; blend=all_mode='overlay':all_opacity=0.7


  



  I get the error, Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_blend_6 which makes me think that it's expecting something like [input 1] [input 2] blend command [output]. The problem is that I need it to overlay and blend.

  



  I tried simplifying the code to just test if the blend operation was working properly.

  



  ffmpeg -i test.mp4 -i logo.png -filter_complex "[0:0] scale=1920x1080 [wm]; [1:0] scale=1920x1080 [prog], [wm][prog] blend=all_mode='overlay':all_opacity=0.7" fart.mp4


  



  I got the error First input link top parameters (size 1920x1080, SAR 1:1) do not match the corresponding second input link bottom parameters (1920x1080, SAR 243:80)
Failed to configure output pad on Parsed_blend_2

  



  So, in addition to the trouble with combining of filters, I'm also having an issue with resizing the watermark as FFMpeg sees it as a different aspect ratio than the other videos.

  



  This is my second day with FFmpeg, so any help would be appreciated.

  



  I'm currently working with FFMpeg version N-61061-gf34cceb

  


• In FFmpeg, using -filter_complex, how can I overlay and blend at the same time ?

  5 mars 2014, par Kristian Boruff

  My code works to combine three videos, resize the videos to 1920X1080, resize the watermark to the correct size, and then overlays the watermark to the lower left hand side. Then converts to the intended codecs for Youtube.
  My question is how do I Blend at the same time using the -filter_complex workflow ?
  Currently, I have the following workflow that does everything but set the opacity

  ffmpeg -y -i fancy movie.mov -i logo.png -i in.mov -i out.mov -c:v libx264 -crf 18 -b:v 50000k -preset veryfast -tune film -profile:v high -x264opts cabac=1:keyint=16:bframes=2:keyint_min=15 -c:a libvo_aacenc -ab 128K -ar 48000 -filter_complex "[0:0] scale=1920X1080 [main]; [2:0] scale=1920X1080 [start]; [3:0] scale=1920X1080 [end]; [start] [2:1] [main] [0:1] [end] [3:1] concat=n=3:v=1:a=1 [prog]; [1:0] scale=480:90 [wm]; [prog] [wm] overlay=36:main_h-overlay_h-45" fart.mp4

  I'm trying to add "blend=all_opacity=0.7" in the last step so the watermark will screen against the background. If I just add

  [prog] [wm] overlay=36:main_h-overlay_h-45, blend=all_mode='overlay':all_opacity=0.7" fart.mp4

  I get the error, Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_blend_6

  If I try a semicolon instead,

  [prog] [wm] overlay=36:main_h-overlay_h-45; blend=all_mode='overlay':all_opacity=0.7

  I get the error, Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_blend_6 which makes me think that it's expecting something like [input 1] [input 2] blend command [output]. The problem is that I need it to overlay and blend.

  I tried simplifying the code to just test if the blend operation was working properly.

  ffmpeg -i test.mp4 -i logo.png -filter_complex "[0:0] scale=1920x1080 [wm]; [1:0] scale=1920x1080 [prog], [wm][prog] blend=all_mode='overlay':all_opacity=0.7" fart.mp4

  I got the error First input link top parameters (size 1920x1080, SAR 1:1) do not match the corresponding second input link bottom parameters (1920x1080, SAR 243:80)
  Failed to configure output pad on Parsed_blend_2

  So, in addition to the trouble with combining of filters, I'm also having an issue with resizing the watermark as FFMpeg sees it as a different aspect ratio than the other videos.

  This is my second day with FFmpeg, so any help would be appreciated.

  I'm currently working with FFMpeg version N-61061-gf34cceb