Create Youtube-ready video from your JPG image and MP3 file, then you can download it as .FLV or .AVI video or directly upload it to Youtube via this site!
JPEG is a commonly used method of lossy compression for picture. You can adjust the compression level, allowing you to choose the best tradeoff between file size and quality. JPEG typically achieves 10:1 compression ratio with a little loss in image quality.
The main reason choosing JPG as the solely supported background image is bacause it is most common format used and distributed. Even your camera has ability to take the picture as JPG image. Or you can get the image you want.
If you need to convert your image to JPG, you can use freely available IrfanView (PC only) or other image viewer. Most of operating system had freeware to convert image from one to other formats. Most of paid-application for image processing such as Photoshop can do this also.
MP3 is a form of audio encoding that use lossy data compression in the process. It is a commonly used audio format for consumer digital audio players.
Why using MP3? Relatively small in size, audio CD-graded sound quality, supported on most of operating system. Widely used by audio player and producer.
There's a lot of choice to convert your audio into mp3 format, such as using sox, ffmpeg, mencoder, audacity (I recommend this, it's free and multi-platform). Try searching on Google using this search term: "free audio conversion tool" you'll find some other alternatives.
Result video quality. All videos produced using mp32u.net will be in .MP4 and .FLV format. The .MP4 is compatible for most of your operating system's stock video player such as Windows Media Player or QuickTime. The video should also works on your conventional DVD player. You can download the video in .FLV format if you want to embed the video on your own blog/site. It is compatible with most of flash player (like jw-player).