I'm trying to record video and audio from my webcam with the following command:
ffmpeg -f v4l2 -input_format mjpeg -s uhd2160 -i /dev/video0 -f pulse -channels 1 -i default video.mpg
but it seems to get stuck in some endless loop at the bottom of the output that looks like this:
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
...
Full output with -report flag enabled: https://pastebin.com/bV1ePJ2u
I can record video and audio separately just fine:
ffmpeg -f v4l2 -input_format mjpeg -s uhd2160 -i /dev/video0 video.mpg
ffmpeg -f pulse -channels 1 -i default audio.wav
So what could be the problem here? I'm on Ubuntu 16.04 kernel 4.14.1
You can combine them into one file by using this command (in cmd for Windows OS)
C:/this is just path of ffmpeg lib/ffmpeg_shared/ffmpeg/bin/ffmpeg -i "video_part.ts" -i "audio_part.aac" -map 0:V:0 -map 1:a:0 -c copy -f mp4 -movflags +faststart "./new/combined_file_name.mp4"
Related
I am trying to setup my linux desktop to be able to view and listent to the device connected to my capture card. I wrote this 2 liner script to be able to do that however my sound is out of tone and a bit distorted, how could I clean it up?
arecord --buffer-time=1 -f cd - | aplay --buffer-time=1 -c 5 -r 48000 -f S16_LE - 2> /dev/null &
ffplay -f video4linux2 -framerate 30 -video_size 1920x1080 -input_format mjpeg /dev/video1 2> /dev/null &
I also tried to do that with ffmpeg piped to ffplay and the sound is crystal clear however there is 2-3 seconds delay on the video and sound, is there a way to fix this?
ffmpeg -framerate 30 -video_size 1920x1080 -thread_queue_size 1024 -input_format mjpeg -i /dev/video1 -f pulse -i 'Analog Input - USB Video' -r 30 -threads 4 -vcodec libx264 -crf 0 -preset ultrafast -vsync 1 -async 1 -f matroska - |ffplay -
Could you try just using ffplay for your second approach?
ffplay -framerate 30 -video_size 1920x1080 \
-thread_queue_size 1024 -input_format mjpeg -i /dev/video1 \
-f pulse -i 'Analog Input - USB Video'`
I could be off-base as I'm only familiar with ffmpeg and don't personally use ffplay, but they share a lot of things (e.g., backend libraries and command line parsing) so I'm hedging this would work.
Also, what do you mean by "there is 2-3 seconds delay on the video and sound"? Are they 2-3 seconds behind what you are physically seeing and hearing? Or are they out of sync by that many seconds?
[addendum]
Not sure if OP is still checking this post, but there is a solution to combine two inputs for ffplay by using an input filtergraph with movie and amovie filters. The following worked in Windows (despite unacceptably large latency):
ffplay -f lavfi -i \
movie=filename=video="Logitech HD Webcam C310":format_name=dshow:format_opts=rtbufsize=702000k[out0]; \
amovie=filename=audio="Microphone (HD Webcam C310)":format_name=dshow[out1]
Note that this is only for the illustration purpose as dshow device can output multiple streams (though the latency is still too bad for real-time use).
The same should be possible in Linux:
ffplay -f lavfi -i \
movie=filename=/dev/video1:format_name=video4linux2:format_opts='framerate=30:video_size=1920x1080:thread_queue_size=1024:input_format=mjpeg'[out0]; \
amovie=filename='Analog Input - USB Video':format_name=pulse[out1]
(Disclaimer: Untested and it may be missing escaping)
The latency may be better in Linux (and with a higher spec'ed PC than mine) so it might be worth a try.
Currently, using ffmpeg, I am using two commands on my Terminal to:
1) create a video from a bunch of images:
ffmpeg -r 60 -f image2 -s 1920x1080 -i rotated-pano_frame%05d_color_corrected_gradblend.jpg -vcodec libx264 -crf 25 -pix_fmt yuv420p test.mp4
2) stream the video to a udp address:
ffmpeg -re -i test.mp4 -c copy -f flv udp://127.0.0.1:48550
I am trying to combine both these instructions into one command line instruction, using &&, as suggested in the answer to a previous question of mine:
ffmpeg -r 60 -f image2 -s 1920x1080 -i rotated-pano_frame%05d_color_corrected_gradblend.jpg -vcodec libx264 -crf 25 -pix_fmt yuv420p test.mp4 \
&& ffmpeg -re -i test.mp4 -c copy -f flv udp://127.0.0.1:48550
but am encountering an error which prevents streaming:
[flv # 0x7fa2ba800000] video stream discovered after head already parsed.
Thoughts on a different command line syntax to join the two instructions, different ffmpeg instruction (filters perhaps?), and why I am getting the error?
Currently, using ffmpeg, I am using two commands on my Terminal to:
1) create a video from a bunch of images:
ffmpeg -r 60 -f image2 -s 1920x1080 -i rotated-pano_frame%05d_color_corrected_gradblend.jpg -vcodec libx264 -crf 25 -pix_fmt yuv420p test.mp4
2) stream the video to a udp address:
ffmpeg -re -i test.mp4 -c copy -f flv udp://127.0.0.1:48550
How can I combine these two commands, into one single ffmpeg command?
A concern I have is that it takes a couple of minutes to generate the video from the images. Therefore, these commands have to happen serially, whereby the second command waits a few minutes for the first command to be completed, before it ensues.
Just add && between the two commands. This will execute the second command if the first executes successfully.
ffmpeg -r 60 -f image2 -s 1920x1080 -i rotated-pano_frame%05d_color_corrected_gradblend.jpg -vcodec libx264 -crf 25 -pix_fmt yuv420p test.mp4 && ffmpeg -re -i test.mp4 -c copy -f flv udp://127.0.0.1:48550
I'd like to record audio from my microphone. My OS is ubuntu. I've tried the following and got errors
$ ffmpeg -f alsa -ac 2 -i hw:1,0 -itsoffset 00:00:00.5 -f video4linux2 -s 320x240 -r 25 /dev/video0 out.mpg
ffmpeg version 0.8.8-4:0.8.8-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav
developers
built on Oct 22 2013 12:31:55 with gcc 4.6.3
*** THIS PROGRAM IS DEPRECATED ***
This program is only provided for compatibility and will be removed in a future release.
Please use avconv instead.
ALSA lib conf.c:3314:(snd_config_hooks_call) Cannot open shared library
libasound_module_conf_pulse.so
ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM hw:1,0
[alsa # 0xbda7a0] cannot open audio device hw:1,0 (No such file or directory)
hw:1,0: Input/output error
Then I tried
$ ffmpeg -f oss -i /dev/dsp audio.mp3
ffmpeg version 0.8.8-4:0.8.8-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav
developers
built on Oct 22 2013 12:31:55 with gcc 4.6.3
*** THIS PROGRAM IS DEPRECATED ***
This program is only provided for compatibility and will be removed in a future release.
Please use avconv instead.
[oss # 0x1ba57a0] /dev/dsp: No such file or directory
/dev/dsp: Input/output error
I haven't been able to get ffmpeg to find my microphone. How can I tell ffmpeg to record from my microphone?
It seems the 'Deprecated' message can be ignored because of this topic
I realise this is a bit old. Just in case anyone else is looking:
ffmpeg -f alsa -ac 2 -i default -itsoffset 00:00:00.5 -f video4linux2 -s 320x240 -r 25 -i /dev/video0 out.mpg
This way it will use the default device to record from. You were also missing a -i before the video capture device - /dev/device0
If you want to get more specific you should take a look in /proc/asound.
Check the cards, devices, pcm files and the card subdirectories. You should be able to glean enough information there to be able to make an educated guess; e.g hw:1,0 or hw:2,0
The documentation may provide further clues:
http://www.alsa-project.org/main/index.php/DeviceNames
The same goes for the webcam - it may not be /dev/video0, perhaps you have an external webcam plugged in and its at /dev/video1 - Have a look in the /dev directory and see whats available
solved !
ffmpeg -f pulse -ac 2 -i default -f x11grab -r 30 -s 1920x1080 -i :0.0 -acodec pcm_s16le -vcodec libx264 -preset ultrafast -threads 0 -y /media/t/TBVolume/desktop/output.mkv
First, list your AV devices using:
ffmpeg -list_devices true -f dshow -i dummy
Assuming your audio device is "Microphone Array", you can use:
ffmpeg -f dshow -i audio="Microphone Array" -c:a libmp3lame -b:a 128k OUTPUT.mp3
Here, 128k is the sampling rate. You can check all options for sampling rates (CBR) here.
./ffmpeg \
-f alsa -async 1 -ac 2 -i hw:2,0 \
-f video4linux2 -vsync 1 -s:v vga -i /dev/video0 \
-acodec aac -b:a 40k \
-r 25 -s:v vga -vcodec libx264 -strict -2 -crf 25 -preset fast -b:v 320K -pass 1 \
-f flv rtmp://192.168.2.105/live/testing
with the above command i able to stream with fps of 25 but their is no audio and video synchronization i.e., audio is faster than video,i am using ffmpeg 0.11.1 version on the pandaboard for an rtmp streaming ,help me out to solve this problem.
Thanks
Ameeth
Don't use -pass 1 if you're not actually doing two-pass encoding.
From the docs (emphasis added):
‘-pass[:stream_specifier] n (output,per-stream)’
Select the pass number (1 or 2). It is used to do two-pass video encoding. The statistics of the video are recorded in the first pass into a log file (see also the option -passlogfile), and in the second pass that log file is used to generate the video at the exact requested bitrate. On pass 1, you may just deactivate audio and set output to null, examples for Windows and Unix:
ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y NUL
ffmpeg -i foo.mov -c:v libxvid -pass 1 -an -f rawvideo -y /dev/null
I was streaming to Twitch, and, funnily enough, removing the -r option made video sync with the audio. Now, you might want to have the framerate limited in some way; unfortunately, I have no solution for that, but it does allow to sync the video with the audio very well.