Libav is a fork of the popular FFmpeg multimedia tool, best known for appearing in the Ubuntu packages
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0answers
20 views
Codec choice for non CPU-intensive video transcoding
I am trying to achieve real-time transcoding of mkv / H264 videos on a low-end (slow CPU) platform.
Using the following command line as a testing harness:
avconv -i test.mkv -c:v mjpeg -q:v 3 -c:a ...
0
votes
2answers
48 views
H264 decompression/decomposition into JPG - quality issues
I'm trying to decode a 1920x1080 30fps h264 stream. Individual frames look outstanding in VLC media player (pausing the playback), but when I decode using avconv (ffmpeg has been deprecated and ...
0
votes
2answers
40 views
Encode mp3 to playback at 1.5x speed in avconv (libav)
I would like to take an mp3 file and re-encode it to play faster (perhaps at 1.5x speed). I primarily use avconv in debian linux, but can use any other program if recommended. I can use any operating ...
0
votes
1answer
33 views
avconv option -c:a copy
I am converting a bunch of videos from FLV to MP4 (for iphone compatibility) and using AAC codec it kept throwing out "invalid audio bitrate" or similar errors. I tried -c:a copy option and it works, ...
1
vote
1answer
53 views
Avconv Can not resample 6 channels
I'm getting a message, that it cannot resample 6 channels into 2 channel audio. This is the command i'm using to convert into h.264+aac:
avconv -i ...
2
votes
1answer
145 views
Converting RGB images into lossless video with avconv / ffmpeg
I am trying to convert a series of PNG24 images containing a screen animation to a lossless video, so that every pixel is reproduced exactly as it was in the original. But avconv (and ffmpeg) both ...
1
vote
2answers
66 views
Bash script to extract audio from video
I have written this little script to batch extract audio from video using avconv. It was working fine, but strangely it doesn't work anymore (since I have changed the codec from aac to mp3).
The ...
1
vote
1answer
165 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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0answers
122 views
Simplest video grab from webcam: how to
On Raspbery Pi's Raspbian (based on Debian Wheezy) I'm trying to make a simplest video grab from a Logitech C910 webcam to a video file via ffmpeg/avconv.
I say:
$ avconv -t 5 -f video4linux2 -s ...
2
votes
1answer
82 views
imagemagick image conversion piped in avconv fails
I am trying to write a script that should take all sort of images (format, size...) and create a video with avconv. I've managed to make it work with a series of jpg (all the same size though) and I'm ...
0
votes
0answers
99 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
...
0
votes
1answer
76 views
How to use avconv filters after encoding?
I have this avconv command:
avconv -i file -s [new size options] -vf "[filters]" /root/converted/1.mp4
Avconv uses the -vf filters before the -s scaling, but I need one avconv command to:
Resize ...
0
votes
0answers
131 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 ...
1
vote
1answer
98 views
Avconv generating HUGE metadata over 90mb for 718mb video file
This is the metadata file, extracted with Atom box studio:
https://www.dropbox.com/s/tok76wospngf854/moov
Video was converted with avconv, info:
/usr/local/bin/avconv -version
avconv version 9.4, ...
2
votes
1answer
131 views
Stream/record desktop, mic and system output
Im try to stream my desktop, and two audio: system output, and mic.
Im using this command, but the audio from my system (hw:0,0) dont hear in output file...
avconv \
-f alsa -i pulse \
-f alsa -i ...
0
votes
1answer
54 views
avconv crashes after ~3 minutes - could be source regression, how do I get last stable version in git?
Application provided invalid, non monotonically increasing dts to muxer in stream 1: 8657 >= 8657
av_interleaved_write_frame(): Invalid argument
[pulse @ 0x2a03400] pa_simple_read failed: Bad state
...
1
vote
1answer
91 views
How do I recompile libav on ubuntu 12.04 without breaking anything
I have a "Little" script for screencasting - I'll skip to the good part.
In my avconv command I record 3 different sources simultaneously to 3 different tracks. The only way I know of getting audio ...
0
votes
1answer
407 views
Install latest libav/avconv on OSX? [closed]
I'm looking for an easy way to grab a working avconv setup on OSX (with working cpu-capabilities).
2
votes
1answer
245 views
how to record/stream multiple audio output from a single input?
This is the command I am currently using to stream live audio under the Raspbian distro:
ffmpeg -f alsa -ac 1 -i hw:1 -ar 44100 -f flv rtmp://10.255.11.53/
The functionality I am looking for is ...
2
votes
1answer
127 views
Extract M4A audio from a video and associate the artwork
Why on Ubuntu 12.04, when I extract audio in M4A from a video (MP4 or FLV, etc.) with avconv:
avconv -i video.mp4 -c:a libvo_aacenc sound.m4a
there is a video stream in it, and if I want only ...
3
votes
0answers
203 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 ...
1
vote
1answer
196 views
Reuse transcoding outputs to generate multiple files with AvConv
I am trying to find information about how to transcode a file into multiple outputs in one shot, but I don't seem to be able to. Most of the results I find describe the opposite: merging multiple ...
0
votes
0answers
68 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 ...
1
vote
0answers
133 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 ...
1
vote
1answer
257 views
User Generated Chroma Key Composite Videos with FFMPEG / AVCONV
I want to create a system where a user can upload two videos to a website, one of which has blue screen in the background, and the website uses AVCONV (or similar) to create a composite video of the ...
2
votes
2answers
1k views
Resizing videos with ffmpeg/avconv to fit into static sized player
I have a html 5 video player which is 700px wide, 400px high. I'm trying to use avconv to use ffmpeg to resize (while retaining the aspect ratio) and making sure it fits into my player.
Input can be ...
3
votes
1answer
173 views
A way to capture error output from ffmpeg/avconv in a bash script
I am trying to batch convert a bunch of files and i am doing an simple listing of the converted files to a text document so that i can stop the script and continue from approximately were i started.
...
0
votes
2answers
221 views
X Error of failed request: BadCursor (invalid Cursor parameter) when recording Xvfb with ffmpeg/avconv
I am trying to record video output from Xvfb using ffmpeg or avconv. I start Xvfb with:
$ Xvfb :29 -screen 0 1024x768x24
When I later try to record display :29 with avconv (same output for ffmpeg):
...
1
vote
1answer
1k views
avconv (ffmpeg) on Raspberry Pi often corrupts extracted video still images
I'm using avconv on a Raspberry Pi to try to fetch a still image from an IP camera with an RTSP stream of H.264 video:
$ avconv -v verbose -i $url -fflags discardcorrupt -t 00:00:01 -r 0.1 -an -vsync ...
2
votes
1answer
290 views
LIBFAAC cannot resample channels
Im using avconv to convert video files into MP4, but whenever I try to encode files with 6 or 8 channels into 2 channels using libfaac I get these error messages:
Can not resample 8 channels @ 44100 ...
1
vote
1answer
440 views
Avconv video merging audio overlays
I join 3 video files using avconv and create a intermediate file, using following syntax
cat inter1.mpg inter2.mpg inter3.mpg > interAll.mpg
inter1.mpg,inter2.mpg contains no audio track.
After ...
1
vote
1answer
859 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 ...
0
votes
0answers
228 views
AVConv increases song duration when converting MP3
I am struggling with the following issue. I want to convert an MP3 ADTS into pure a MP3. I am using AVConv on Ubuntu 12.10. The outcome is a file that has the same size, but the duration is now ...
0
votes
1answer
107 views
Only video playback not working for Xbox using uShare
I have been mucking around with video encode for a while now using Handbrake without any success. (just recently tried EncodeHD on a Windows machine with no luck) So far all music and pictures play ...
6
votes
2answers
8k views
libav vs ffmpeg - better to use libav (avconv) today?
From what I've seen it looks to me like libav is thought to become a successor of ffmpeg, is that correct? If that's true why is that so? What exactly is libav doing better and why should I choose it ...
2
votes
0answers
161 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, ...
2
votes
0answers
1k 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 ...
0
votes
0answers
856 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 ...
1
vote
2answers
3k views
Using avconv (ffmpeg) to concatenate a bunch of .bmps into a mkv/avi video
Trying to figure out how to get avconv to concatenate a bunch of .bmps together into a video file.
Here's what I've got so far:
avconv -f image2 -i Capture/%d.bmp -vcodec mpeg4 -r 24 -b:v 20M ...
4
votes
1answer
7k views
avconv giving error on audio stream
Trying to convert an mkv file to avi:
avconv -i 1.mkv ./converted/1.avi
Getting this output:
avconv version 0.8.1-4:0.8.1-0ubuntu1, Copyright (c) 2000-2011 the Libav developers
built on Mar 22 ...

