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• How to stop ffmpeg user screen recording in c#

  14 juin 2016, par Akash Langhani

  I am using ffmpeg in application and It start and record video perfectly but when I want to stop it ask for press "q", so how can I pass "q" to process which is in runing state from application.

• Access two different webcams with same name ffmpeg dshow

  14 juin 2016, par Luke E

  I'm using ffmpeg to stream video from two webcams of the same type, and thus the same device name when selecting a dshow device with 'video="device name"' I would like to access both of them at the same time, but they seem to be indistinguishable using this approach. On https://www.ffmpeg.org/ffmpeg-devices.html#dshow I managed to find the following example code, which appears to be using some hardware id to reassign it a pin number, but for the life of me I can't figure out how I would identify the hardware id of my webcams such as to use this example.

  ffmpeg -f dshow -audio_pin_name "Audio Out" -video_pin_name 2 -i video=video="@device_pnp_\\?\pci#ven_1a0a&dev_6200&subsys_62021461&rev_01#4&e2c7dd6&0&00e1#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\{ca465100-deb0-4d59-818f-8c477184adf6}":audio="Microphone"
  

  Any help is very much appreciated.

• ffmpeg modify audio length/size ( stretch or shrink)

  14 juin 2016, par mido

  I am developing a web app, where people can record videos. I have been able to send chunks of audio n video to server successfully, where I am trying to combine them and return as single proper file.

  my problem is if the recording is for one hour, after merging the chunks

  video length : 1:00:00 , audio length : 00:59:30,

  now, this is not a issue of audio not getting recorded( I have checked that), the problem is, somehow, when i merge the chunks of audio, it shrinks,

  I find that it is progressive sync issue where it gets worse and worse as time increases.

  I have searched the net for the solution, most places say async, I have tried using it, but to no avail, is the below usage correct?

  ffmpeg -i audio.wav -async 1 -i video.webm -y -strict -2 v.mp4

  (v.mp4 is the final file that I provide to the users.)

• how to modify movie filter in ffmpeg using zmq

  14 juin 2016, par ramon1604

  So far, we can modify overlay, scale and others but we do not find the proper syntax to modify movie filter in ffmpeg. We are using perl to send zmq command to ffmpeg and it returns 0 success when command is properly received. Please help. thanks

• Mix two decoded FFmpeg AVFrame* objects of audio into one AVFrame*

  14 juin 2016, par williamtroup

  I'm currently using FFmpeg to decode frames from an audio file and add them to a new stream that is being written to a video. This all works correctly, but I was wondering how one would go about mixing two AVFrame* objects together (after they are decoded).

  I've mixed PCM data before, but was wondering if FFmpeg had a built in API to do the work more effectively.

  I'm currently using the FFMpeg AutoGen project in C# to do my work.