The Path to the Video is considered to be the entire process from the capture at the source (sporting events, news, etc) until it gets to the final user.
The video signal, at the source, requires a very high bandwidth to be properly carried, which calls for compression methods that allow for its distribution without perceptual quality losses. From the moment it is captured until it is viewed by the final user, the signal goes through different processes, which can be classified in the following basic stages as shown in the figure.
- Contribution. – From its capture to its arrival to the final head-end.
- Distribution, Last Encoding step. Here is where the image quality gets more deteriorated to adapt to the different channels established in the broadcasting.
- Broadcasting.- Final distribution to the final user through different means (Satellite, DTTV, cable, IP, Mobile)
During this process, the content will be re-encoded in the different editing and post-production processes. The last encoding process will take place in the final distribution head-ends to be decoded and viewed by the final users. This is known as Multi-Generation, and causes a progressive quality deterioration in the video signal. There are techniques to maintain the quality levels as high as possible in the first steps (Contribution Stage).
It is in the final Distribution stage where the highest bandwidth reduction takes place, and therefore, the highest signal deterioration.
According to different studies, several conducted by Sapec, considering the deterioration that occurs in the final stage, it is essential to arrive with the highest quality possible to this last point.