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0answers
11 views

Libav, slow internet, the golden median

Some time ago I was to configure a streaming service, unfortunately there were surprises at every corner... (awesome official bugs, delays on deliveries and etc.) After tweaking around a lot I found ...
0
votes
0answers
42 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 ...
0
votes
1answer
105 views

speed up video using avconv without quality loss

After having read this page, I'm using avconv (which in this case is apparently same as ffmpeg, and which I need to use instead since I'm on Ubuntu trusty) to speed up a .swf video. I don't want a ...
0
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0answers
93 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 ...
0
votes
0answers
46 views

Converting with avconv without trying to increase quality

This might just be a quick question or a matter of a specific flag, but I have a standard format that I use for storing videos on my computer. The idea is to cut down on storage requirements while ...
0
votes
0answers
309 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 ...
0
votes
0answers
149 views

using avconv to convert rbga image sequence into video while preserving alpha chanel

Is there any way to use "avconv" to convert a sequence of png images with alpha channel into a video and preserving the alpha channel? $ avconv -f image2 -framerate 60 -i img_%5d.png -r 29 foo.mp4 ...
1
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2answers
2k views

reduce size of mp4 using avconv

I'm looking at this question Reduce size of MP4 and I want to do it using avconv, however, I'd also like to shrink the frame size by about half. My problem is when I do avconv -i "$file" -s 640x480 ...
0
votes
1answer
328 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 ...
2
votes
1answer
196 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 ...
2
votes
1answer
2k 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
267 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
1k 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
291 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 orĀ 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 ...
1
vote
0answers
298 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 ...
3
votes
1answer
543 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. ...