1. DVD Ripping Tool: A qualified DVD ripping program maintains timely updates and adopts advanced tech to deal with DVD ripping.
2. DVD-ROM Drive's Read Speed: When the ripping process starts, the DVD disc will be spinning in the DVD drive. But if the reading speed of the DVD drive is not fast or a spinning DVD gets stuck, it will definitely slow down DVD ripping speed. That's the reason why it spends less time in ripping a DVD ISO image or Video_TS folder saved on your local drive.
3. Computer Configuration: Your computer configuration is an important factor affecting the DVD ripping process. If you have the latest driver installed on your computer and are using a decent graphics card, the DVD ripping process will be shortened certainly when the GPU acceleration is enabled.
4. DVD Capacity: Compared with converting a single-layer DVD without any settings altered, it takes a lot of time to convert a dual-layer DVD disc (DVD5 vs DVD9).
5. DVD Encoding Method: Due to different output format settings, the processing time will vary. DVD-video always uses MPEG-2 as its video codec. When you convert DVD to MPG with MPEG-2 codec, there is no transcoding process, which will take less time to finish the process than you convert DVD to MP4 or MKV with H.264 codec. It could be said that MPG is the best format to rip a DVD. Other settings like changing video resolution can also make the process shorter or longer.
Now hope you get the gist of the key points about how long does it take to rip a DVD.