These collection of frames are often referred to by the rather non-technical sounding name of a “group of pictures”, abbreviated as GOP. This process works through using keyframes, also known as an i-frame or Intra frame, and delta frames, which only store changes in the image to reduce redundant information. This is a video compression technique that divides frames into macroblocks and then looks for redundancies between blocks. This realization gave birth to the idea of interframe prediction. So if that plant in the example is not going to change, why not just keep using the same elements in some of the subsequent frames to reduce space? As a result, that’s a lot of wasted bandwidth used just to convey that something hasn’t changed.Ĭonsequently, when looking for effective ways to compress video content, frame management became one of the cornerstone principles. For example, if someone is talking while standing next to a motionless plant it’s unlikely that information related to that plant will change. On an average video, if someone were to take 90 consecutive frames and spread them out they will see a lot elements that are pretty much identical. So content created that uses a FPS of 30 means there are 30 “still images” that will play for every second of video. Usually denoted as FPS (frames per second), each frame is a still image that when played in sequence creates a moving picture. Starting at a high level, most probably realize that video content is made up of a series of frames. To understand this relation, one first needs to understand video frames. A keyframe is an important element, but really only part of a longer process that helps to reduce the bandwidth required for video. As someone matures as a broadcaster, it pays to understand elements in greater detail to learn why a process is done and also optimal settings.įor example, a keyframe is something a few broadcasters have seen mentioned before, or saw the setting in an encoder like Wirecast, without quite realizing what it is and how beneficial this process is for streaming. There are a lot of terms and aspects of streaming technology that can be taken for granted. Should someone use an “auto” keyframe setting?.What’s the best setting for a keyframe Interval?.Relationship between keyframes and bitrates.Choosing a keyframe interval at the encoder Level.What are b-frames and how do they differ from p-frames?.This article describes this process in detail, while also giving best practices and ideal encoder settings that you can apply for use with your live streaming platform. In particular, it overlooks a fascinating process called interframe, which involves keyframes and delta frames to intelligently compress content in a manner that is intended to go unnoticed. This sells short, though, the complexity that actually goes into compressing video content. But also you have to compress more bits per second so the gpu needs more resources to do this task.The default mental image of video compression involves unwanted video artifacts, like pixelation and blockiness in the image. But the total upload bandwich is increased. Higher Keyframe are more stable and will erase transmission artifacts more frequently. The explosion then will be shown muddy and unsharp and will sharpen over time. This is somtimes to heavy for the given compressiin and video bandwich. a explosion will spontaneously cause the bandwich of a full frame. To degenerate the picture not that much you send a full frame to discribe delta from periodically.Ī longer keyframe interval spares calculation power a not a full frame must be compressed to h.26xĪlso the total upload bandwich will be decreased.īut rapidly changes between two keyframes e.g. Only where you si and movement is going on there will be traffic going on. So if you have a something like you sit in front of the camera, the background in the corners will not get any delta values from the keyframe and so there is bandwich spared. So for modern video codecs a keyframe is a frame that contains a full frame also a complete image.Īll following frames are not discribed as an full i.age rather only difference in the frame before are sent.
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