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• How do I make a C# win form program that breaks a video down to frames, then put those frames back together to make a video ?

  30 juillet 2015, par Atom Scott

  First, I’m fairly new to C sharp so I’m looking for a thorough and easy to understand answer.

  How do I make a C# win form program that breaks a video down to frames, then puts those frames back together to make a video ?
  I also want to be able to select which frames to extract by setting an interval time. For example, extract frames that are one second apart.
  Is this possible, I have done some research but I don’t understand how to use the codes displayed on the following websites.

  Supposedly code to breakdown video into frames. However I do not know where to put it. Do I make it the event for a button or something. From my own research I am guessing this uses ffmpeg. But I’m not exactly sure how to use ffmpeg, I have tried downloading Aforge, and use Aforge.Video.ffmpeg. But I’m stuck there.
  http://www.researchgate.net/post/Has_anyone_code_in_C_to_read_video_file_and_split_it_into_frames[^]

  Code for making a video from images, it looked promising so i tried to copy and paste it visual studio. However the line using BytescoutImageToVideoLib ; has an error asking me whether I am missing a reference. What reference am I missing ?
  http://bytescout.com/products/developer/imagetovideosdk/imagetovideosdk_first_step_with_visual_c_sharp_net.html[^]

  I also noticed that there was a page on code project for something similar to this, but the downloadable demo project didn’t work at all. I didnt see the point in spending time on something where the end product is broken.
  http://www.codeproject.com/Articles/13237/Extract-Frames-from-Video-Files

  Any help is greatly appreciated.

• Using ffmpeg rtmp stream a static image and audio input [on hold]

  30 octobre 2017, par Chad

  Using a Raspberry Pi, stream audio in and use a static image as the video input thru ffmpeg over RTMP to a Cloud video provider (DaCast in this instance)

  So far, I’ve gone through many blog posts, Stack Overflow questions, and package documentation. I’ve found that most of the posts are no longer valid with the newer versions of ffmpeg. Or don’t quite line up with what I am trying to achieve.

  However, I have figured out the right settings to stream the Raspberry Pi Camera v2 with the audio in.

  ffmpeg \
    -f alsa -ac 1 -i plughw:1,0 \
    -f v4l2 -s 1920x1080 -r 30 -input_format h264 -i /dev/video0 \
    -vcodec copy -preset veryfast -r 15 -g 30 -b:v 64k -ar 44100 -threads 6 -b:a 96k -bufsize 3000k \
    -f flv rtmp ://streaming_server_url
  

  But can’t seem to get it right to replace the video input with a static image.

  I have tried removing the 3rd line and adding -loop 1 -i '/path/to/image.jpg'

  The logs look like :

  [alsa @ 0x55e4b980] Thread message queue blocking ; consider raising the thread_queue_size option (current value : 1024)
  [alsa @ 0x55e4b980] ALSA buffer xrun.  0kB time=00:00:00.00 bitrate=N/A speed=   0x
  [alsa @ 0x55e4b980] ALSA buffer xrun.130kB time=00:00:00.27 bitrate=3822.5kbits/s speed=0.0403x
  ...
  

  I have also tried looping a 4 second video, with similar outcomes.

  ---

  My Setup for context :

  • Raspberry Pi 3 Model B
  • USB Audio Device (Sabrent USB External Stereo Sound Adapter)
  • Ubuntu MATE 16.04.2 (Xenial)
  • ffmpeg version 3.2-2+rpi1 xenial1.7 (I can post what is configured with the build, if needed)

• HLS with FFmpeg, browser skips m3u8 in sequence

  16 octobre 2019, par Jongseok Yoon

  I’m writing a program with C++, receiving 2-second-long mp4 video and converting it to m3u8 and same-duration ts files in real-time.

  Problem is when I check it with browsers on PC, it doesn’t load m3u8 properly.

  For example, when I start to watch m3u8, it loads first m3u8 with #EXT-X-MEDIA-SEQUENCE : 1, then it keeps loading first m3u8, then suddenly skips to #EXT-X-MEDIA-SEQUENCE : 4 or larger.

  Streaming still works, but it is very unstable due to that problem. It loads some ts together, then loads nothing while loading same m3u8 it already loaded, and skips 3 or more m3u8 and loads ts files together and again.

  ffmpeg -loglevel level+warning -i SOURCE.mp4 -an -filter:v fps=fps=10 -f hls -hls_list_size 7 -strftime 1 -hls_segment_filename '1.ts' -hls_flags append_list+omit_endlist DEST.m3u8

  This is ffmpeg command in my program, using hls_segment_filename option to overwrite ts files so I limit number of files under 100, and it runs every 2 second.

  Maybe, I’m overwriting it too fast to be loaded ?