Fornax Fornax96

I hereby claim:

To claim this, I am signing this object:

	func videoThumbnail(ps *pixelstore.PixelStore, sourceFile pixelstore.FileID) (image.Image, error) {
	// To generate thumbnails from video files we use FFMPEG. One challenge is
	// that FFMPEG needs to seek to the end of the video to decode the stream
	// metadata. Saving the whole file to disk would be inefficient. Luckily
	// FFMPEG supports reading (and seeking) videos over HTTP. Here we start a
	// HTTP server on a random TCP port, then the address of the listener is
	// given to FFMPEG to read the file from. When FFMPEG exits we shut down the
	// listener and the HTTP server. The resulting thumbnail image is piped to
	// stdout and saved in a buffer. The buffer is then decoded and returned
	// from the function

	package util

	// ExecutionLimiter is a utility which limits the concurrent execution of a
	// function. When it is initialized it creates a channel with x capacity and
	// fills it with x booleans. Every time the Lock() function is called a bool is
	// removed from the channel. When the channel is empty the function will block
	// until the Unlock function is called, which puts a new bool into the channel.
	type ExecutionLimiter struct {
	channel chan bool
	}