Video streaming from the cloud to a computer with no loss in quality is achieved through a variety of techniques and technologies. It's important to note, however, that "no loss in quality" might not always be accurate. In many cases, there is some loss in quality during the process, but it's minimized to the point that it's not easily noticeable to the human eye.
Here are some key aspects that make high-quality video streaming possible:
1. Compression: Videos are often compressed before they're sent over the network, which makes them smaller and easier to transmit. This is usually done using a codec, which is a software that can encode a stream or data for transmission and then decode it for viewing or editing. Codecs use complex algorithms to remove redundant or irrelevant parts of the video data, which results in a smaller file size without a significant loss in perceived quality.
2. Adaptive Streaming: Adaptive streaming (like HTTP Live Streaming or HLS, and Dynamic Adaptive Streaming over HTTP or DASH) is a technique where the video quality is adjusted on-the-fly based on the viewer's network conditions. If the viewer's network speed drops, the video quality is lowered to avoid buffering. If the network speed improves, the quality is increased. This is done by having multiple versions of the video at different quality levels (resolutions and bit rates) available on the server.
3. Content Delivery Networks (CDNs): CDNs are networks of servers spread out geographically, which store copies of the video. When a user requests a video, it's sent from the server that's geographically closest to them. This reduces the amount of time it takes for the video to reach the viewer, which can improve the quality of the streaming experience.
4. Buffering: When a video is streamed, a certain portion of it is loaded ahead of time. This is known as buffering. The buffer acts as a sort of cushion, so if there are any delays in the video data being transmitted, the video can continue to play smoothly from the buffer.
5. High Bandwidth Networks: With the advent of high-speed internet connections, large amounts of data can be transmitted quickly, which supports high-quality video streaming.
Despite these methods, the quality of streamed video can be affected by various factors including the original video quality, the user's device and display, internet bandwidth, network congestion, and more. But with advances in technology, the gap between streamed video quality and original video quality continues to narrow.