0
votes
0answers
5 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 ...
1
vote
1answer
30 views

Video concatenating, with overlay

I have a video recorded from a gopro which is split into 3 parts as the maximum filesize is reached after about 17 minutes and the gopro automatically splits it into multiple parts. I also have a ...
0
votes
1answer
55 views

How to convert any video to .avi with wmv1 codec using ffmpeg/avconv?

I have installed ffmpeg to convert a video. I am trying to convert a .mp4 to a .avi video with the codec wmv1. How to do this? I am using the command avconv in a Kubuntu terminal. Last attempt I did ...
0
votes
1answer
420 views

What is the difference beetween ffmpeg and libav, and how to chech which one is used for application? [duplicate]

I am working with some gstreamer based application and some other streaming stuff and I came to some confusion: What is difference between libav and ffmpeg? I found no explanation what are they and ...
0
votes
1answer
591 views

ffmpeg/avconv async is not working - unsync audio

I have a javascript that records video from a webcam as webm and audio from microphone as wav together. I am encoding these webm and wave files to generate a mp4 file using ffmpeg/avconv. But i've ...
1
vote
0answers
342 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 ...
0
votes
1answer
269 views

avconv gets killed if mkv has subtitles

What I'm trying to do is to take a movie (in an Matroska container), convert all audio tracks to AC3 and don't touch anything else. I'm using this line: avconv -i infile.mkv -map 0 -vcodec copy ...
2
votes
1answer
2k views

Burn-in subtitles with avconv?

I have a mkv file and want to convert it to an DVD compatible mpg file with avconv. How can I also burn-in one subtitle stream from the same mkv file? avconv -i input.mkv -map 0:0 -map 0:1 -target ...
1
vote
1answer
130 views

Where in FFmpeg is the DTS decoder located?

Where is the actual DTS decoder located? When I search through the FFmpeg folders, dtsdec.c and dtshddec.c show up, but they're only 2–4 kB, and don't have any actual decoding code anywhere within ...
1
vote
1answer
358 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
1k 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
1answer
2k 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 ├── ...
1
vote
1answer
786 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
363 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 ...
2
votes
1answer
342 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 ...
2
votes
1answer
614 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 ...
3
votes
0answers
448 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
951 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 ...
6
votes
2answers
6k 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
416 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
660 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): ...
0
votes
1answer
168 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 ...
12
votes
2answers
19k views

libav vs ffmpeg - better to use libav (avconv) today? [closed]

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
254 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
1k 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
4k 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 ...