Libav is a fork of the popular FFmpeg multimedia tool, best known for appearing in the Ubuntu packages. Include the full, uncut console output when asking for help with a command.

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How to install libav manually for Video Download Helper on Windows 7?

I'm trying to get the Firefox Extension "Video Download Helper" (VDH) to convert and record videos. The suggested way of doing this is to install a precompiled version of libav called "Convert Helper" ...
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3k views

How do I merge a folder of PNG images to a mp4 movie using avconv?

I have a folder containing many time stamped PNG images which I'd like to merge to a short movie. The contents of that directory looks like this: └── images ├── img_20130421_115547.png ├── ...
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1answer
268 views

avconv stream to rtmp via nginx-rtmp-module - convert into html5 file/stream

just keeping things short at the beginning. I stream via rtmp with avconv through a nginx configuration. Catching that stream onto a website is only possible via flash as far as i know. Nowadays ...
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1answer
813 views

How to use avconv or ffmpeg to convert any video to an exact size and shape

We have a system that supports streaming video, but we support multiple players. I have multiple systems that I COULD use for this. Currently, I've been using the media server that we use to stream ...
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1answer
2k views

Encoding multiple video streams with a single avconv invocation

I played with avconv on Ubuntu and I'm now able to e.g. record the desktop with sound from a soundcard. One thing I wanted to do was recording two video inputs at the same time, for instance the ...
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300 views

Basic conversion of sequence of images to avi with avconv

I'm trying to convert sequnce of images to small avi. Each image should be shown 2 seconds. I'm using this basic command sudo avconv -r 0.5 -i test%05d.jpg out.avi I get the output, but it shows ...
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594 views

Concatenate .mp4 videos of different encoding parameters using avconv without losing quality?

How can I use the avconv tool to concatenate multiple .mp4 videos of different encoding parameters in a single container, without losing quality?
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1answer
628 views

Convert mkv with AVC High@L4.0 to mp4 with ACV High@L4.1 or higher

I am trying to convert some mkv files I have to mp4 so that they can be played to my chromecast. Here is the information about the video files. mkv file information As you can see that the video ...
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1answer
77 views

How can I make the output format of a video the same as the input format?

How can I make the output format of a video the same as the input format for general case? avconv -i source -vcodec copy -acodec copy -movflags empty_moov -f ??? output I would not like to use -f ...
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984 views

How can I record a video signal in Linux from the command line?

I have a Linux machine with a Pinnacle video card. I wanna record a video signal from my TV connected to the S-Video input in my Pinnacle card. I could record using VLC GUI, but I wanna cron it, so I ...
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1k views

How do I merge two videos and increase sound volume using Avconv?

I'm trying to merge two cd-s into 1 file and also boost sound volume 200%, I tried this using avconv tool, but I only got cd1 and without an boost in sound: nohup avconv -i cd1.avi -i cd2.avi -vcodec ...
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665 views

Accurate and reliable movie editing with avconv

I'm trying to perform movie editing in an automated way with avconv. It is made in two steps: extract some parts of an input movie: concatenate the parts to form an output movie: I tried some ...
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179 views

How to correctly use x265 lossless parameter with avconv

x265 has a lossless mode which is used for ultra-high bitrates with zero loss of quality. I tried using this mode with avconv as follows: avconv -i input.mp4 -c:v libx265 -x265-params lossless -c:a ...
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855 views

Why does avconv change the fps when deinterlacing?

I have a .MTS 1080i of 25fps (mediainfo) that I deinterlaced with avconv -i input.MTS -vf yadif -c:a copy output.mp4. As the wiki says, the default value for yadif is 0 which "outputs one frame for ...
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583 views

Non monotonically increasing dts to muxer in stream 1

I have an error with 1gb videofile and avconv Application provided invalid, non monotonically increasing dts to muxer in stream 1: 177873 >= 177849 av_interleaved_write_frame(): Invalid argument ...
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2k views

Avconv increases file size

I am using the version of avconv in Ubuntu 12.04 to archive videos. I would preferably use some kind of lossless video compression (e.g., huffyuv or FFV1), but using the original video stream (copy ...
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Cropping with avconv

I am trying to crop a video with avconv avconv -r 25 -i test.avi -vf "crop=out_w=in_w" -b 1024k test2.avi but avconv tells me Invalid chars '=in_w' at the end of expression 'out_w=in_w' whatever ...
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928 views

avconv stream video from USB webcam without delay

I need to stream video from USB webcam. I am using avconv, but it has delay min 5s. Is possible to stream in real time without delay? avconv -f video4linux2 -i /dev/video0 -vcodec libx264 -f mpegts ...
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420 views

ffmpeg/avconv crashes when video frame isn't expected size

I'm capturing my webcam using ffmpeg/avconv, but I keep running into this problem: The v4l2 frame is 828212 bytes, but 829440 bytes are expected And then it crashes. It should just skip that frame, ...
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Use avconv and image magick to convert video into reduced size gif

I'm using this answer to convert a video capture of a small section of my screen to a gif for a tutorial on a webapp. The problem is that the gif conversion increases the file size. avconv -i ...
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libav - readability of text from high resolution to low viewing resolution

Scenario: Trying to create a screencast of a linux system for a tutorial.. The two monitors I have are a combined (3400x1200).. When I play it back on a windows machine, either using VLC or Windows ...
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avconv / ffmpeg covert images to video skips frames when frame type changes

I have an instance of ffmpeg that captures one fps from our home CCTV cameras. At the end of the day I have an ffmpeg script that takes those images and turns them into a video. This is fine with one ...
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793 views

How do I get avconv/ffmpeg to output video with specific tbn, tbc

My father can only use an old video editor (Pinnacle Studio 12) that is very picky on what video files it imports. Here is the output of avprobe one of the videos it manages to import: encoder: ...
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260 views

FFmpeg / libav / Avconv settings to add higher contrast to a video

I successfully convert videos to mp4 from images turning the video black and white, is there a way to add contrast and brightness to balance the higher contrast so that it looks sharper? Here is the ...
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315 views

Access to IP camera stream

I'm trying to set up three IP cameras I got for using them in ZoneMinder. According to the webinterface of the camera, the stream can be viewed at: http://192.168.47.202:8090/live.asf But, since I'm ...
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Using avconv to convert an animated gif to mp4 with sound

I want to convert an animated gif and a midi (music) file into a mp4 video. Is it possible? I saw a lot of topics on documentation, foruns and stackexchange sites, but I didn't find. It works with 1 ...
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534 views

Why can't I seem to get the framerate right when using avconv to convert a sequence of images to a gif?

I need to convert a series of images to gifs. I found three broad ways to do this. One involving ImageMagick, One involving gifsicle and another involving avconv. I can't use Imagemagick because ...
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227 views

Piping images to avconv at unknown fps

I am currently reading images from a camera "as fast as possible" (>50fps), outputting them as JPEGs, and piping them to avconv using the image2pipe input. What is a good approach to getting the ...
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571 views

Use avconv to convert iMovie DV streams to other formats

I have a bunch of DV streams that were imported from a DV camcorder using iMovie. Unfortunately, neither avconv nor VLC seem to be capable of converting these files correctly, whereas QuickTime ...
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418 views

AVCONV errors while grabbing af stream from an IPCAM

When im trying to grab a stream from my D-Link DSC-932L Cam, using avconv, I keep getting errors. Depending of framerate etc. the proces will terminate whitin a minute. Here is the string and common ...
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avconv - Error for scale filter

I'm trying to rescale a video via avconv with the following command: /usr/bin/avconv -i /home/user/video.mp4 -filter:v crop=960:720:160:0,scale=h=498:w=-1 -an -y -frames:v 1 media/image.png But I'm ...
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38 views

How to redirect video subtitles to pipe?

I am watching subtitled videos. I would like the subtitles to be sent to a pipe instead of being displayed on the video. The aim is to process the subtitle data with some other software, like sed, in ...
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0answers
71 views

openRTSP default 25fps encoding (not 24)

I want to capture the RTSP stream from some IP cameras, and after looking around I found 2 great tools to do this: avconv and openRTSP openRTSP -u user password ...
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issue sending user and password in VLC

Basically I have a net where I can do this without problem: vlc rtsp://10.48.1.10/mpeg4/media.3gp --rtsp-user=user --rtsp-pwd=password but when I do this: vlc ...
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51 views

avconv combined audio and video streams, mplayer fails to play audio

I have a movie.avi file compressed with DivX which I'm trying to recompress with H264. I compressed the video stream with x264, leaving the audio as is. I'd prefer to compress everything at once, but ...
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130 views

avconv Error “Header missing” while converting mkv audio to AAC

I want to convert Videos from MKV (h.254 + MP3) to MKV (h.264 + AAC), because the Chromecast no longer supports MKV with MP3. When I try avconv -y -i /media/user/Data/toImport/Fr\ S02-01\ Das\ ...
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577 views

streaming to rtmp using avconv or ffmpeg

I have an IP webcam HiSilicon Hi3516C that I can successfully access from a raspberry pi. I can get still images by using a command like this: avconv -i "rtsp://192.168.1.10:554" myfile.jpg now ...
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117 views

Pipe remote jpg webcam image to ffmpeg as video

I have a cheap ip webcam. All it provides is a single http url to a static jpg file. Such as http:///image.jpg. Repeatedly requesting the same url will provide subsequent frames from the ip camera. ...
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26 views

avconv - how to use two input files for transcoding to maximize quality

Let's say I have two video files encoded in lossy formats, for instance sample.mp4 (H.264) and sample.265 (H.265). Now I want to transcode to sample.webm (VP8). We all know transcoding degrades video ...
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98 views

avconv stream dies after 2 hours

I have a live stream running from a Raspberry Pi camera using the following command: avconv -f h264 -r 25 -i fifo.264 -metadata title="Raspberry Pi Camera Module (LIVE)" -f flv ...
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100 views

How to constrain/stretch a video to a fixed duration using ffmpeg or avconv?

So I have a few hundred clips of videos, about 1 to 5 seconds each, that I'd like to all play at 2 seconds each...this means for the 1 second videos, they get stretched out, and the 5 second videos, ...
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0answers
306 views

avconv and ffmpeg: errors reading png files

I'm trying to use avconv to overlay data onto a video. I generate PNG files representing the overlay data at 4fps. The PNG files are the 120px wider and 60px taller than the original video, because ...
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141 views

Force avprobe format detection

I have a gif file without an extention called loop. the command avprobe loop returns: [mp3 @ 0x7faa59004a00] Format detected only with low score of 1, misdetection possible! avprobe subsequently ...
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183 views

Ubuntu Screencasting: Libavdevice segmentation fault

I'm trying to stream to twitch a screencast of a remote desktop, but I meet some segmentation fault. The OS is: Xubuntu 14.04 , xfce, x2go I tried with Ubuntu 14.04, Ubuntu 12.04, ffmpeg and avconv, ...
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327 views

Converting RAW Blackmagic Intensity Card frames

I am trying to convert raw video frames that I have captured using a Blackmagic Design Intensity card. The output frames are of the format: YCbCr 4:2:2 packed 8 Bit UYVY Abekas How can I convert ...
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393 views

FFmpeg/Avconv: Scaling Filter “Error when evaluating the expression”

I'm trying to scale a video with FFmpeg with the following command: ffmpeg -i input.jpg -vf scale="'if(gt(a,4/3),320,-1)':'if(gt(a,4/3),-1,240)'" output_320x240_boxed.png This is taken verbatim ...
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715 views

Understanding avconv console output

I'm using avconv to broadcast a video on justin.tv from my Raspberry Pi. I get it (weakly) working a very few times. Most of the times justin.tv is not being updated and says "disconnected". The ...
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594 views

avconv overlay for live video

I want to combine two stream and I want a single stream with both video in a single stream by simultaniously, both stream want to be visible at a time left half first video should be there and right ...
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632 views

How to loop audio when mixing with longer movie in avconv

Is it possible to loop audio when mixing with longer movie using avconv? I want music to repeat itself through whole movie. In avconv manual i found parameter "-flags loop" but it doesn't work. Music ...
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2k views

avconv and ffmpeg - drawtext filter text_w evaluates as 0 in Ubuntu Precise

I'm attempting to draw text onto a video using either the avconv or ffmpeg commands. When specifying x= for where on the final video to place the text, the 'text_w' value is evaluating to 0, rather ...