The Inputs Tab
MJPG-streamer is made for streaming video from a UVC camera, but it includes the option of streaming two alternating still images instead of a video feed. This is useful if you want to check the operation of MJPG-streamer independently of your camera. StreamMinder features a check box at the top of the Inputs tab that allows you to use this test image if you so desire. Because MJPG-streamer only allows one input to be used, checking this check box will disable the camera input.
Within the Camera group box, three settings are availble. The "Video device" combo box allows you to select the camera to use, based on its device name in your system's /dev directory. MJPG-streamer only supports UVC-compatible cameras, so StreamMinder checks all video devices to see which ones are UVC cameras (as opposed to, say, TV tuner cards or non-UVC devices) and shows only compatible devices. If you have more than one UVC camera plugged in, you can choose which one to use from the combo box. If the combo box is empty, that means no UVC cameras were recognized.
The "Image size" combo box allows you to select the size of the image to be captured from your camera. Currently supported resolutions are 640x480, 800x600, and 960x720. Some cameras may support higher resolutions, and MJPG-streamer will even allow you to use those higher resolutions, but they require the image format to be an uncompressed YUY rather than a compressed JPG. Uncompressed images may work fine over a high-speed (480Mb/s) USB line, but don't do well over 100Mb/s Ethernet and are quite useless for streaming over the Web. I don't intend to support the uncompressed format unless there's a very high demand for it.
The "Frames per second" spin box allows you to choose the frame rate at which images will be captured from the camera. Valid values range from 1 to 30, though what you see in your Web browser depends mostly on what frame rate your connection can support. Obvisouly, if you're viewing the output on the same machine that the camera is plugged into, then you'll get the full frame rate that you asked for (as long as your image rendering engine can keep up, which is often CPU-bound). But if you're trying to view 960x720 images from a remote computer over a DSL connection, be prepared to wait a while between frames, regardless of what frame rate the host machine is getting from the camera.
One note about the range of available frame rates: The 960x720 image size only allows frame rates up to 15 frames per second in MJPG-streamer, so StreamMinder will enforce that limit for that image size.