Qualitative video analysis

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This page documents some techniques that are useful if you want to carry out analysis of musical material from either a music DVD, from a video downloaded from the web, or from your own video recordings. Please also refer to the introduction to quantitative video analysis for more information.

Contents

Source material

DVD

If you want to store files from a DVD to your hard drive, you will have to "rip" the files. This used to be a non-trivial task, but it is not so difficult when you understand some of the basics and get the right tools. This is how to do it (and assumes that you are only doing this to your own DVDs!):

First you need to download and install the following programs:

  • VLC is a video player which is needed for being able to play back zone-protected DVDs on your system without having to set to another region (if your computer asks you to change your region you should just avoid this, since VLC will work anyway).
  • Handbrake is a program that handles the "ripping" of video from the DVD and sends it to the compression engine.

Which settings to use? There are so many video formats around, and it is difficult to say that one is better than the other. There are also various engines converting into the same format but at different speed and with different quality. The rule of thumb is that MPEG-4 is the preferred format to use, but there are several different versions of MPEG-4... Too many people just give up on the whole thing, so the best advice is to use any format that you manage to install and get working on your system!

Here are some suggested settings that give decent result:

  • Video: MPEG-4 (either H.264 or FFmpeg)
  • 2-pass encoding
  • Bitrate: this depends on the size of the video, but 1500 kbps is often ok.
  • Crop your video to remove the black lines surrounding the image. This both makes a better-looking video file, and gives a smaller file size.
  • Deinterlace the video (typically use fast deinterlace) to remove unwanted horizontal lines in the video file.
  • Audio: 160 kbps AAC stereo.
  • Select the correct audio track that you want to store. Notice that many music-DVDs often provide multiple audio tracks to choose from (e.g. 5.1, stereo, etc.).

Web downloads

There are several video services online that allow you to watch videos. Some of these also provide the possibility to download files, but all of them. Youtube, for example, is a great source for video material, although many at a fairly low resolution. While there is no option to save files directly from Youtube, there are several thirdparty solutions for doing this. The simplest is probably to use Kickyoutube. When you find a file that you want to download from Youtube, you simply type "kick" in front of the URL and you get an option to store the file.

Tips:

  • Store your file as an .MP4 file rather than .FLV (Flash video).
  • If you download a .FLV and can't get it to play back on your computer, you can open it in QuickTime Pro and save it as a QuickTime movie. This will not recompress the file, it will only camouflage the flash video content as a QuickTime movie.

Personal recording

A third way of getting digital video material for your music research is to record it yourself! Digital video cameras are dropping in price all the time, and even the cheapest consumer cameras offer decent image quality.

Tips for transferring to computer: Most new video cameras offer the possibility to transfer your video to a computer. If the material is on a DV-tape, you will need to record the files to your computer through the camera, connecting it with either a USB or a FireWire cable. Then you can record from the camera using e.g. iMovie on Mac or Windows Movie Maker on Windows, or any other video editing application you have lying around.

For harddrive based cameras, on the other hand, it is often as simple as connecting the camera or plugging in your memory card and copy over the files. These files are typically recorded in different formats, e.g. MPEG-2, AVI, MOV. You can recompress these files, but since this is your raw material it is good to always keep the original in case you want to recompress to another format later on.

Analysis

Here we are going to focus on qualitative analysis, where the video material is going to be used for observation and annotation.

Text editor

Perhaps the most basic and simple way of doing this is by manually extracting frames from the video file, pasting them into a text editor and type your comments below. We have found that the best software to take a screen capture from is QuickTime. On Windows there seems to be a restriction when using Windows Media Player or VLC, so if you try to make a screen capture this will only work as long as the source file is up and running, and will disappear when you close it down.

  • Mac: press shift+cmd+3 to take a picture of the whole screen, or shift+cmd+4 to select a region to take a picture of.
  • Win: press "print screen" to copy a picture to the clipboard, then paste (ctrl+v) it into your document.

Videonotetaker

Videonotetaker is a very simple, yet easy-to-use video annotation software. It is based on Java and Quicktime, and runs on both OSX and Windows.

Anvil

Anvil is a video annotation tool made for speech/behaviour analysis, but can also be used for musical applications. It works on all platforms, but requires Java to be installed. It is also possible to import the results of audio analysis from Praat into Anvil, which makes it useful for music analysis.

Sequencer

Yet another way of doing this is to use a music sequencer with video support for doing the analysis. This was first described by Rune Fagereng, and is a clever (tough somewhat odd) way of carrying out video analysis if you already have a sequencer program on your computer. Since a sequencer allows for presenting multiple MIDI tracks, you can (ab)use this functionality to write your annotations into the tracks.

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