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Questions tagged [webm]

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

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11 views

I can't run streaming video WebM with Icecast2 both on Windows and Linux

I trying run a stream using WebM format, but it don't running. The image below show the web page with loading always but not loaded. Is important notice, I made two servers, one linux and other ...
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0answers
138 views

Extracting Opus from WebM losslessly with FFmpeg or MKVToolNix

I have come across a strange problem when remuxing Opus audio stream from WebM to another container like ogg or opus. Running the output files through a spectrum analyzer clearly shows that there is ...
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526 views

How to disable WEBM and GIF playback (Open video in new tab) in Chrome?

An analogy might make my intention clear. It's very easy to disable images in Google Chrome: Go to Settings, Click on 'Advanced' and scroll down to 'Privacy and security', where the option to disable ...
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1answer
771 views

How do I remove all metadata from a WebM file?

I've tried using ffmpeg, but it seems to keep all the metadata I'm actively looking to remove. I'm looking to remove ALL metadata, including length, bitrate, etc. Before you say this isn't possible, ...
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162 views

VirtualBox: webm files deleted, can't start guest OS

Configuration: Virtualbox5.2.22 on Win7 host running a LinuxOS guest. I was running out of diskspace and found several large size *.webm files under: /VirtualBox VMs/LinuxOS/ These files were said ...
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1answer
186 views

WEBM video looks correct in browsers, but not in video players

Ive been trying to figure out why a webm video renders incorrectly on my desktop... The correct file can be seen here, however, downloading the file, and trying to play it in VLC/MPC-HC produces a ...
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2answers
184 views

Find duplicate WEBM files

I have a large collection of files in webm format. Some of them are duplicates. They have totally different names, but their content is the same. It is annoying to find them by myself and then delete ...
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0answers
4k views

FFmpeg - convert WebM/Opus to WAV or FLAC in single step?

I want to create WAV and FLAC audio files from WebM files with Opus audio streams, and I want to do so without further degrading the audio. I am currently using a 2-step process as follows (WAV ...
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706 views

ffmpeg WebM to MP4: awful video quality

I'm trying to convert a WebM video coming from a webcam to an MP4 x264 format. I tried to use this ffmpeg command: ffmpeg -stats -nostdin -y -flags global_header -i "/home/Foto/incoming-video/2017-05-...
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0answers
284 views

What is the difference between webm and webm_chunk?

I am asking because I cannot check this myself, when running ffmpeg with "webm_chunk" format I get either "Output file #0 does not contain any stream" or "Could not write header for output file #0" ...
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1answer
521 views

FFmpeg fails to convert webm files when h264_nvenc forced

I have been working with below environment. ==>Ubuntu 16.04.3 ==>FFmpeg :3.4.2 -- configuration: --prefix=/usr/local/ffmpeg_new/ --enable-cuda --enable-cuvid --enable-nvenc --enable-nonfree --...
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2answers
10k views

What does Matroska have which WebM doesn't, that made the differentiation necessary?

I've read that WebM is essentially a subset of the Matroska format. What does Matroska support that WebM doesn't, which necessitated "christening" a new format rather than just saying "WebM = Matroska ...
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1answer
3k views

Is it ok to rename webm (audio-only) files to .opus?

For .webm files obtained with youtube-dl-f bestaudio containing no video stream, is it preferable to run ffmpeg -i input.webm -vn -c:a copy output.opus or can one simply rename the source file, ...
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0answers
103 views

How can I inspect the file structure of DASH injected webM files?

So we know after injecting DASH information, WebM files will have the init chunk and index chunk for DASH. How can I inspect the structure of the WebM files to understand the position of these chunks ...
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0answers
346 views

Converting video int Webm using ffmpeg, file size

I have found this article from google describing how to convert video into webm https://sites.google.com/a/webmproject.org/wiki/ffmpeg/vp9-encoding-guide I used following command to convert video ...
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1answer
1k 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....
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2answers
2k 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] ...
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0answers
334 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 ...
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1answer
572 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 ...
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1answer
348 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 ...
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1answer
3k 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 ...
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1answer
54 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 ...
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1answer
2k 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....
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1answer
1k 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 ...
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1answer
2k 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 ...
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2answers
727 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 ...
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1answer
756 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 ...
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3answers
13k 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. ...
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3answers
88k 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.
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3answers
1k 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 ...
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1answer
1k 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 ...
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1answer
639 views

IE will not seek audio/webm file

I'm trying to create a WebM audio file that will play back and seek in all browsers using the HTML5 <audio> tag and MIME type audio/webm. I've found workarounds to get this to work in all ...
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0answers
124 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't ...
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1answer
10k 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 ...
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1answer
812 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 ...
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1answer
1k 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 ...
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0answers
159 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 ...
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1answer
5k 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 ...
2
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1answer
3k 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 ...
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1answer
2k 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 ...
18
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1answer
23k 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% ...
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2answers
3k 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 (...
12
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2answers
6k 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 ...
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3answers
2k 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 ...
12
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1answer
8k 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
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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 ...
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1answer
321 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.
3
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1answer
4k 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/...
12
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1answer
5k 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 ...
7
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3answers
4k 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 ...