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• Setup FFMpegCore in Visual Studio 2019

  27 juillet 2022, par DsiakMondala

  I am confused on the basics of using a library. I understand that there is a library called FFMpeg and a wrapper called FFMpegCore so we can use FFMpeg with C#, correct ? I downloaded both FFMpeg and FFMpegCore and I have them in my project's folder. Although I didn't perceive any class named FFMpegOptions in either of the file's folders.
I am stuck on how to actually set it up so I can use it in my little project, I never downloaded someone's library before. Can somebody please walk me though the motions of connecting the three of them together ?

  


  So far I experimented with :

  


  

  • Add a reference to my project, but there doesn't seem to be any .dll, .tlb, .olb, .ocx or .exe files to add

  


  • Add an existing project to my solution. There is a project called FFMpegCore.csproj but adding it raises a missing SDK error. Weirdly enough, opening the same project as a standalone doesn't raise any issues which makes me thing the operation I am trying is inadequate.

  


  


  I am sure this is a silly and easy setup to perform but I just don't know enough to find a solution.

  


• Converting mkv file to mp4 gives me `filenotfounderror`

  8 juillet 2022, par Justin

  Here is the script being used :

  


  import os
import ffmpeg

start_dir =r'C:\Users\Videos_2'

def convert_to_mp4(mkv_file):
    name, ext = os.path.splitext(mkv_file)
    out_name = name + ".mp4"
    #ffmpeg.input(mkv_file).output(out_name, format = 'mp4', acodec ='aac', ar=16000, audio_bitrate=96000 ).run()
    ffmpeg.input(mkv_file).output(out_name, format = 'mp4', acodec ='aac', ar=16000, audio_bitrate=96000 ).run()
    print("Finished converting {}".format(mkv_file))

for path, folder, files in os.walk(start_dir):
    for file in files:
        if file.endswith('.mkv'):
            print("Found file: %s" % file)
            convert_to_mp4(os.path.join(start_dir, file))
        else:
            pass


  


  It is similar to the following : Converting mkv files to mp4 with ffmpeg-python

  


  It gives me the error FileNotFoundError: [WinError 2] The system cannot find the file specified on the line convert_to_mp4(os.path.join(start_dir, file)). From the link provided it says to fix the problem "Make sure ffmpeg.exe is in the same directory as the script." However I do not understand exactly what that means. I downloaded ffmpeg through the terminal window in the environment that I am using.

  


• Can't scrub frame by frame through .mp4 files in VLC created using FFmpeg command line, but changing container to .avi can scrub frame by frame in VLC

  16 juin 2022, par ICBanMI

  I wrote a really simple demonstration of the issue. I create a 4k video that is 150 frames, and output it to mp4. When I open that in VLC(Vent 3.0.17.4), I can scrub forward a few frames at the beginning(e key) before it stops entirely. If I move it towards the end of the file( 4 secs), it can't scrub forward at all.

  


  What I found out through testing. I can scrub forward/backward 3 seconds normal in vlc. I can scrub forward frame by frame using quicktime's latest version(2016). If I mux it to .avi file format, scrubbing using the e key works as expected in VLC. Copying the meta data from an mp4 that can scrub forward frame by frame doesn't change anything. Renaming the .mp4 file to .avi doesn't fix the issue... only muxing out to an avi does. Using a build of version 5.0.1 of ffmpeg.

  


  I included both VLC commands in code. I'd be more than happy to walk way from this with just muxing everything to avi... but .mp4 is a requirement along with being able to scrub forward frame by frame in VLC. Not sure if code or command line is where the issue is... as sample mp4s from the net used in VLC don't appear to have this issue.

  


  #include <iostream>&#xA;#include &#xA;&#xA;int main()&#xA;{&#xA;   FILE *m_pFFmpeg;&#xA;&#xA;   // Working - Can scrub forward frame by frame in latest version of vlc&#xA;   //const char *cmdOutput = "ffmpeg -hide_banner -y -r 30 -s 3840x2160 -f rawvideo -pix_fmt rgb24 -i - -framerate 30 -an -vcodec libx264 -pix_fmt yuv420p -video_track_timescale 30 -vf vflip -preset veryslow -qp 0 output.avi";&#xA;   &#xA;   // Not working - Can&#x27;t scrub forward frame by frame in latest version of vlc. Only difference is the .mp4 at the end&#xA;   const char *cmdOutput = "ffmpeg -hide_banner -y -r 30 -s 3840x2160 -f rawvideo -pix_fmt rgb24 -i - -framerate 30 -an -vcodec libx264 -pix_fmt yuv420p -video_track_timescale 30 -vf vflip -preset veryslow -qp 0 output.mp4";&#xA;  &#xA;   int g_x_dis_res = 3840;&#xA;   int g_y_dis_res = 2160;&#xA;&#xA;   m_pFFmpeg = _popen(cmdOutput, "wb");&#xA;&#xA;   uint8_t *export_buffer = new uint8_t[g_x_dis_res * g_y_dis_res * 3];&#xA;&#xA;   for (int i = 0; i &lt; (g_x_dis_res * g_y_dis_res * 3); i&#x2B;&#x2B;) {&#xA;      export_buffer[i] = 127;&#xA;   }&#xA;&#xA;   for (int j = 0; j &lt; 150; j&#x2B;&#x2B;) {&#xA;      fwrite(export_buffer, 3 * g_x_dis_res * g_y_dis_res, 1, m_pFFmpeg);&#xA;&#xA;      printf("Export Frame %d\n", j &#x2B; 1);&#xA;   }&#xA;&#xA;   delete[] export_buffer;&#xA;&#xA;   fflush(m_pFFmpeg);&#xA;   _pclose(m_pFFmpeg);&#xA;&#xA;   return 0;&#xA;}&#xA;</iostream>