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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 I’ve found that most of the posts are no longer valid with the newer versions of ffmpeg.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)

• Insert video into another video both of different formats in a time efficient way

  7 février 2017, par Sharath Huddar

  I have an assignment which requires that the code I write takes a large video(1 to 3 hrs) and a smaller video (10-60 seconds) and the smaller video is inserted at intervals of 30 minutes into the larger video. Note that the videos are not necessarily in the same format.

  I tried to encode the large and the small video to a common format (mp4) and then split the large video based on time (while encoding it to mp4) and then concat all the videos in a predefined sequence (also while encoding to mp4). All these operations were carried out using FFMPEG.

  Although this method worked, it too close to 20 hours to perform the whole operation on an Intel NUC (having an i5 processor and 8GB RAM)

  Is there a faster way to do this without compromising on quality ?