Continuing my explorations of FFmpeg for video visualization, today I came across this very nice blog post on creating “pixel array” images of videos. Here the idea is to reduce every single frame into only one pixel, and to plot this next to each other on a line. Of course, I wanted to try this out myself. I find that creating motiongrams or videograms is a good way to visualize the content of videos....
{width=“300”} This is a note to self, and could potentially also be useful to others in need of converting “old-school” MPEG-2 files into more modern MPEG-4 files using FFmpeg. In the fourMs lab we have a bunch of Canon XF105 video cameras that record .MXF files with MPEG-2 compression. This is not a very useful format for other things we are doing, so I often have to recompress them to something else....
Very many people are currently moving to video-based meetings. For that reason I have written up some quick advise on how to improve your setup. This is based on my interview advise, but grouped differently. Network {width=“200” height=“100”} The first important thing is to have as good a network as you can. Video conferencing requires a lot of bandwidth, so even though your e-mail and regular browsing works fine, it may still not be sufficient for good video transmission....
I am continuing my explorations of the great terminal-based video tool FFmpeg. Now I wanted to see if I could “flatten” a 360-degree video recorded with a Ricoh Theta camera. These cameras contain two fisheye lenses, capturing two 180-degree videos next to each other. This results in video files like the one I show a screenshot of below. These files are not very useful to watch or work with, so we need to somehow “flatten” them into a more meaningful video file....
I am happy to announce a new version of VideoAnalysis, a standalone application for OSX and Windows for creating visualizations and extract motion features from video files. VideoAnalysis was developed as a standalone version of the Musical Gestures Toolbox. I began working on the toolbox back in 2004, as a collection of modules for Max/MSP/Jitter. Then some people asked me to make a standalone version with some of the core functionality....
In some recent posts I have explored the creation of motiongrams and average images, multi-exposure displays, and image masks. In this blog post I will explore different ways of generating keyframe displays using the very handy command line tool FFmpeg. As in the previous posts, I will use a contemporary dance video from the AIST Dance Video Database as an example: The first attempt is to create a 3x3 grid image by just sampling frames from the original image....
As part of my exploration in creating multi-exposure keyframe image displays with FFmpeg and ImageMagick, I tried out a number of things that did not help solve the initial problem but still could be interesting for other things. Most interesting was the automagic creation of image masks from a video file. I will use a contemporary dance video from the AIST Dance Video Database as an example: The first step is to extract keyframes from the video file using this one-liner ffmpeg command:...
While I was testing visualization of some videos from the AIST database earlier today, I wanted to also create some “keyframe image displays”. This can be seen as a way of doing multi-exposure photography, and should be quite straightforward to do. Still it took me quite some time to figure out exactly how to implement it. It may be that I was searching for the wrong things, but in case anyone else is looking for the same, here is a quick write up....
Researchers from AIST have released an open database of dance videos, and I got very excited to try out some visualization methods on some of the files. This was also a good chance to test out some new functionality in the Musical Gestures Toolbox for Matlab that we are developing at RITMO. The AIST collection contains a number of videos. I selected one hip-hop dance video based on a very steady rhythmic pattern, and a contemporary dance video that is more fluid in both motion and music....
We just started a new run of our free online course Music Moves. Here we have a tradition of recording wrap-up videos every Friday, in which some of the course educators answer questions from the learners. We have recorded these in many different ways, from using high-end cameras and microphones to just using a handheld phone. We have found that using multiple cameras and microphones is too time-consuming, both in setup and editing....