Install FFmpeg with homebrew. You'll need to install it with a couple flags for webm and the AAC audio codec.
brew install ffmpeg --with-libvpx --with-libvorbis --with-fdk-aacc --with-opus
If you already have ffmpeg installed, but not with the other libraries, use the reinstall
command.
brew reinstall ffmpeg --with-opus
FFmpeg options. The -c:v
option is an alias for -vcodec
and -c:a
is an alias for -acodec
. -crf
is Constant Rate Factor.
This method allows the encoder to attempt to achieve a certain output quality for the whole file when output file size is of less importance. This provides maximum compression efficiency with a single pass. Each frame gets the bitrate it needs to keep the requested quality level. The downside is that you can't tell it to get a specific filesize or not go over a specific size or bitrate.
When converting to an MP4, you want to use the h264 video codec and the aac audio codec because IE11 and earlier only support this combination. The FFmpeg and H.264 Encoding Guide can walk you through some of the H.264 specific options.
ffmpeg -i input.mov -vcodec h264 -acodec aac -strict -2 output.mp4
For maximum compatibility, use the profile
option. This may, however, increase the bit rate quite a bit. You can disable the audio stream with the -an
option. -pix_fmt yuv420p
is for Apple Quicktime support.
In this example, input.mov
is converted to output.mp4
with maximum compatibility, with Quicktime support, and without an audio stream.
ffmpeg -an -i input.mov -vcodec libx264 -pix_fmt yuv420p -profile:v baseline -level 3 output.mp4
libvpx
is the VP8 video encoder for WebM. FFmpeg and WebM Encoding Guide will walk you through webm specifics.
In this example, input.mov
is converted to output.webm
with a constant rate factor of 10
(lower is higher quality) at a bitrate of 1M
. Changing the bitrate to something lower (e.g. 700K
) will result in lower file sizes and lower quality. If your video does not have audio, you may leave off the -acodec libvorbis
part.
ffmpeg -i input.mov -vcodec libvpx -qmin 0 -qmax 50 -crf 10 -b:v 1M -acodec libvorbis output.webm
VP9 can encode videos at half the file size 😄👏 You can check out Google's VP9 encoding guide for their recommend settings or the FFmpeg VP9 guide.
Here's an example from the FFmpeg guide:
ffmpeg -i input.mov -vcodec libvpx-vp9 -b:v 1M -acodec libvorbis output.webm
And here's Google's "Best Quality (Slowest) Recommended Settings". You need to run the first line(s). It will create a log file (and warn you the out.webm is empty). On the second pass, the video will be output.
ffmpeg -i <source> -c:v libvpx-vp9 -pass 1 -b:v 1000K -threads 1 -speed 4 \
-tile-columns 0 -frame-parallel 0 -auto-alt-ref 1 -lag-in-frames 25 \
-g 9999 -aq-mode 0 -an -f webm /dev/null
ffmpeg -i <source> -c:v libvpx-vp9 -pass 2 -b:v 1000K -threads 1 -speed 0 \
-tile-columns 0 -frame-parallel 0 -auto-alt-ref 1 -lag-in-frames 25 \
-g 9999 -aq-mode 0 -c:a libopus -b:a 64k -f webm out.webm
As of January 2015, all major browsers support MP4.
Data current as of March 2017. Sourced from jwplayer's research and caniuse for mp4 and webm.
Edge 14+ has partial support for VP9
Browser | H264 | H265 | VP8 | VP9 | AAC | MP3 | VORBIS | OPUS |
---|---|---|---|---|---|---|---|---|
Chrome for Desktop | 30+ | - | 30+ | 30+ | 30+ | 30+ | 30+ | 33+ |
Chrome for Android | 30+ | - | 30+ | 30+ | 30+ | 30+ | 30+ | - |
IE | 9+ | - | - | - | 9+ | 9+ | - | - |
IE Mobile | 10+ | - | - | - | 10+ | 10+ | - | - |
Edge | 12+ | - | - | 14+ | 12+ | 12+ | - | 14+ |
Firefox for Desktop | 22+ | - | 20+ | 28+ | 22+ | 22+ | 20+ | 20+ |
Firefox for Android | 20+ | - | 20+ | 28+ | 20+ | - | 20+ | 20+ |
Safari for Mac | 3+ | - | - | - | 3+ | 3+ | - | - |
Safari for iOS | 3+ | - | - | - | 3+ | 3+ | - | - |
Opera for Desktop | 25+ | - | 11+ | 16+ | - | - | 11+ | 12+ |
Android Stock Browser | 2.3+ | - | 4.0+ | - | 2.3+ | 2.3+ | 4.0+ | - |
Since all browsers except Opera support MP4, we can use WebM's VP9 codec for modern browsers and fall back to MP4s for the rest.
<video>
<source src="path/to/video.webm" type="video/webm; codecs=vp9,vorbis">
<source src="path/to/video.mp4" type="video/mp4">
</video>
Here's their guide. Output a single frame from the video.
ffmpeg -i input.mp4 -ss 00:00:14.435 -vframes 1 out.png
Output one image every second as a jpg.
ffmpeg -i input.mp4 -vf fps=1 out%3d.jpg
FFmpeg cannot reverse a video by itself. One way to reverse a video is to use After Effects' Time-Reverse Layer.
- Open After Effects. Drag your clip in to the project and then into the timeline.
- Right click on your video clip layer and choose Time.
- From the Time menu, choose Time-Reverse Layer ⌥⌘R
- Export lossless as an .mov. (Choose Composition and then Add to render queue).
- Not sure if required - Convert to h.264 mp4 with and Adobe Media Encoder
- Following encoding steps as usual.