Sponsored by Google, WebM is a new protocol used to convert audio/video files to HTML 5 compliant feeds.

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0
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1answer
20 views

ffmpeg - Is it possibe to retain real timecodes using -copyts?

It's is a simple task. I want to make a converted clip of a video using -copyts to have it's real timecodes. For example, the converted clip of this command: ffmpeg -hide_banner -ss 57:41.76 -i input....
0
votes
0answers
5 views

Webm big play button doesn't play the video

When I click the big play button that's in the center of a webm (see image) the video doesn't play. It just shows the animation of the big play button disappearing. I have to click the small play ...
1
vote
1answer
2k views

How do I split a WebM file without re-encoding?

I have this WebM file that I need to split, but I'd like to do it without re-encoding. Putting it in an MKV container doesn't work, because the point where I need to split it is not a keyframe, so it ...
1
vote
1answer
173 views

Extract alpha channel from webm video

I'm trying to extract a mask from a webm video with alpha transparency: ffmpeg -i test.webm -vf "alphaextract" -y output.mp4 But I'm getting an error: [Parsed_alphaextract_2 @ 0x7f924b700d00] ...
0
votes
0answers
79 views

FFmpeg script to convert all WebM files in a folder to Gif, and then delete the WebM files

I'm using FFmpeg with DirectoryMonitor, a folder watching program. When a webm is added to the folder i want to execute a script to convert all webm files in that folder to gif, and then delete those ...
0
votes
0answers
79 views

FFAStrans walkthrough to transcode webm to gif

I would like to use the watch folder features to detect when a webm file is downloaded, and convert it to gif. I'm a bit lost with the UI though. Thanks for reading and help mucho grande appreciated.
0
votes
1answer
88 views

FFMpeg image sequence to video using VP9 encoder

I'm trying to transcode mp4 to webm format in a lossless way. I tried two ways to do that. For that purpose, I extracted mp4 video to image sequences (png). Then, I converted image sequence(without ...
0
votes
1answer
75 views

How do I transcode/compress mp4 source files on the Linux command line?

I have some rather large mp4s produced by my phone. They aren't very long, so they're probably not very compressed. What's an example of using a command line Linux tool to transcode one of these to ...
0
votes
1answer
79 views

Correcting for wildly incorrect time of .webm with FFMPEG

I have a file that when I run ffpmeg -i on it will display a time of 351909:41:29.64. I know I didn't record for 40 + years. Any suggestions on what would be the best way to fix this? I ...
1
vote
3answers
941 views

Seek Issues in WebM (VP8 IVF/OGG) File

I have a file downloaded from the web this is the media below. General Format : WebM Format version : Version 2 File size ...
0
votes
1answer
35 views

How can I locate a local html file that has been loaded into the browsers element inspector?

Since there don't seem to be any video players with a seamless loop, I've been opening my webms through Firefox since the webm player is capable of seamless looping. Problem is every time I open a ...
0
votes
1answer
197 views

Compiling libvorbis with MinGW

I'm attempting to cross compile libvorbis ready to then do the same for libvpx to ultimately compile a windows version of ffmpeg that can handle WebM (along with a few other options that I've yet to ...
0
votes
0answers
19 views

Does WebM expire?

Recently, I was told by a client that one of his recordings (a .webm file) said that it had expired and so he could no longer play it. I haven't found documentation to that effect, but I'd like to ...
1
vote
1answer
235 views

How can I convert a series of images to WebM in FFmpeg?

I’ve got a series of JPG images going from 108-AN-001 to 108-AN-045. I need to convert these into a single WebM video file. I've tried this command: ffmpeg -f image2 -i 108-AN-%03d.jpg -vf 12 output....
0
votes
1answer
234 views

How to mux Vorbis audio and VP8 video into WebM format with ffmpeg?

I have a Vorbis audio and VP8 encoded video, and would like to mux them into WebM format. How do I mux them with FFmpeg, and also set the display aspect ratio to 16:9? I'm using Windows 7 with the ...
5
votes
2answers
3k views

WebM on Mac OS X

What options are there for playing WebM video files on Mac OS X other than VLC? A plugin to Quicktime Player would be perfect.
0
votes
1answer
452 views

How to Resize WEBM Videos

I find that a lot of the webm videos (or gifv) on imgur and the like are too small to see (yes, my eyesight is horrible). These types of videos allow for viewing in full screen, but since the source ...
10
votes
2answers
32k views

What's the easiest way to save a GIFV as a simple GIF?

Usually I open the context menu right clicking on the image. Now theres no option for "save image as", just options for the WEBM/MP4 format.
-2
votes
3answers
4k views

Conversion from WebM to MP4 in Ubuntu is slow and bad quality

I have used the command ffmpeg -i input.webm -q:v 10 -c:a copy out.mp4 I also tried using avconv instead of ffmpeg. The conversion is successful but the quality is bad. Also it takes a lot of time....
11
votes
3answers
9k views

Lossless extraction of streams from WebM

I would like to extract streams from WebM video files without converting them (re-compression), can somebody recommend any software that can allow this?
2
votes
1answer
416 views

Why does FFmpeg segment_times create webm files with incorrect duration and start times?

I have a MOV file that I want to split into several smaller files (at certain timestamps in a comma-separated list). I'm simultaneously compressing the video into WEBM files. The command I'm using ...
-1
votes
1answer
274 views

FFMPEG conversion from webm to mp4 intermittent on Ubuntu 14.04 [duplicate]

I am trying to convert .webm file that we get from google's screencastify to .mp4 file. I need it to be playable using Windows Media Player. I need it the file to be playing with all the WMP versions ...
10
votes
1answer
4k views

What bunch of ffmpeg scripts do I need to get HTML5-compatible “Video for everybody”?

What list of commands should I do in ffmpeg/mencoder/some_other_CLI_app to get a video in all the right formats to use Video for Everybody? i.e. Is there a subtlety that prevents there being a ...
0
votes
3answers
321 views

combining 1 image + 1 audio using FFmpeg

I want to combine an audio file and one image file into a video. Output will be in .webm format so I will be using libvpx. The video must have one frame with the best/lossless quality. So far I have ...
0
votes
1answer
587 views

ffmpeg constant rate factor for different webm qualities

So i came across the following question What is the right way to calculate 1080p 720p 360p 240p quality? But that is for H264 MP4 files. For MP4 files i set the -crf constant rate factor as 18 for ...
5
votes
0answers
204 views

IE will not seek audio/webm file

I'm trying to create a WebM audio only that will playback and seek in all browsers using the HTML5 tag and mime type audio/webm. I've found workarounds to get this to work in all browsers, but they ...
2
votes
1answer
6k views

FFmpeg “ass” filter not working

I'm haveing a bit of a problem when trying to use FFmpeg. I've mostly been using it to extract clips from videos and such. However, I've been trying to get some subtitles embedded (hardsubs) into the ...
0
votes
0answers
98 views

Video is not playing on any of browsers

When I am trying to open Google Material Design Spec and click on play button nothing happens. Checked on Chrome, Opera, Firefox. When I am trying to open video url directly, first time - it doesn'...
0
votes
1answer
465 views

FFmpeg error when doing first pass of WebM encoding: Unrecognized option 'auto-alt-ref'

I'm using OS X Mavericks (10.9.4) and installed ffmpeg from homebrew. When executing this command (assuming input file exists): ffmpeg -i ololo.wmv -vf scale=500:-1 -auto-alt-ref 1 -lag-in-frames 20 ...
3
votes
1answer
857 views

How do I convert webm to mp4 for MacOSX?

I'm on MacOSX Lion and would like a method for converting webm to mp4 (or another iTunes compatible format). ffmpeg seems like a possibility but the documentation is a bit obtuse for me; step-by-step ...
2
votes
1answer
3k views

Why are my WebM files larger than OGG and MP4 versions?

I have some OGG and MP4 files and I am converting them WebM for use on my website. I have used VLC to convert to WebM. What I have noticed is the WebM file is 8MB while the MP4 and OGG are around 1-...
1
vote
0answers
130 views

error while merging videos with ffmpeg

I am trying to concat videos with different resolutions using ffmpeg and I am encountering this error shown below while that the video resizes when playing the videos I merge them using ffmpeg with ...
2
votes
1answer
2k views

Merge segments from different videos ffmpeg

Could I use ffmpeg to make one video which takes different segments from different videos? 1.webm, 2.webm, 3.webm, 4.webm Those are my 4 video files. I want the 10 seconds from each video. The ...
3
votes
1answer
1k views

How do you combine multiple ffserver streams into a grid in real time?

I'm trying to set up a CCTV system with ffmpeg/ffserver/zoneminder and want a nice looking 4x4 grid without all the Java applet borders and window dongles on it, just a full screen 4x4 grid. I've ...
16
votes
1answer
19k views

Converting video to WebM with ffmpeg/avconv

While trying to optimize the size of my home videos I converted some of them to WebM as a test, using Pitivi on Xubuntu. The size difference is significant. The resulting webm-file is only around 10% ...
3
votes
2answers
2k views

In which format to store home made videos

TL;DR: my home videos are taking up too much space and are impractical to backup on Dropbox. Which format do you advice to convert them to? Long version: One year ago I bought a new compact camera (...
2
votes
2answers
5k views

Working FFMPEG settings for converting to WebM format?

Can anyone give me working settings for converting video to WebM with ffmpeg? I am on Windows 7 with the FFmpeg git-67f5650 64-bit Static (Latest) build from http://ffmpeg.zeranoe.com/builds/ I've ...
8
votes
1answer
4k views

Does WebM have its own delivery method? How does it relate to RTMP and HTTP Live Streaming?

When I read up on streaming media formats and packaging methods, I am confused by the way WebM is described as mutually exclusive to RTMP and HTTP Live Streaming. From my understanding, WebM is a ...
2
votes
1answer
2k views

Transcode videos to webm with lossless compression

I am using GNU/Linux(Arch Linux), and i need to transcode some videos from .avi/.mov to .webm. I don't have the original file for most videos, only the "very compressed" .avi, and i can't loose any ...
0
votes
1answer
303 views

How to make YouTube search results to be of webm format in Firefox?

In Google Chrome there is an extension that add &webm=1 in all YouTube search URIs. I did not find an alternative add-on in Firefox, any alternative methods? Thanks.
2
votes
1answer
3k views

mkvmerge error “formats do not match” when appending oga files

we're using mkvmerge to concat user uploaded audio into a single file (this is all done from code in a django website). The command line looks like mkvmerge -o /path/to/output.webm -w /file/to/...
5
votes
2answers
2k views

Joining webm videos under Linux

How can I concatenate several .webm files (e.g. downloaded from youtube) into a single file? I've tried a simple cat followed by "mencoder -forceidx -oac copy -ovc copy ..." - didn't work. I'm using ...
0
votes
0answers
100 views

Encoding to WebM and OggVorbis without changing original dimensions?

Trying to convert original Quicktime.movs to both WEbM and OggVorbis-Theora formats. Was using the free Miro video converter but when it converts it always uses preset sizes. Is there any way of ...