![]() ![]() H53QmxZ-rOs: Downloading video info webpage Here's the output from the tool with a random 60fps Youtube video: C:\>youtube-dl -F A tool like youtube-dl allows you to do that. For examples, you can look at YouTube's 60fps videos and specifically the sizes of the actual video files behind different quality settings. Offline compression can yield better results though. On my phone and camera, 60fps videos are almost exactly twice the size of 30fps videos, probably because they don't have too much processing power to spare on smart compression and simply double their framerate to remain on the safe side. However if you decrease the distance of intra-coded pictures in order to compensate for possible packet-loss or bitstream errors, you will carry more overhead and therefore the increase is more than linear, not much, but probably noticeable.Īlso asked myself this question today. If this rate of intra-coded pictures doesn't increase, we could assume a linear growth in file size, maybe a bit more. However, we have to insert an intra-coded picture every once in a while which isn't dependent on any other picture. The above only applies to B- or P-pictures, which depend on others. ![]() The only overhead we have to add is the overhead from small residuals that can't be arithmetically coded in an efficient way. The encoder will do its best job to encode all the motion in the video, which in sum is the same (just in smaller steps, if you know what I mean). To summarize, nothing much changes on that side. Then again, you have twice as many pictures per second, which means that – in average – the encoded information doubles again. It depends on the algorithmic coding implemented.) (We must not forget that only half of the residual does not mean half of the data needed to store it. In average, this will be half of the residual. In the end, an object moves from point A to B, so its motion vector will be the same length no matter how many frames per second.Īs the encoder looks for the difference between two (or more) frames and only encodes the residual values, that means it will have to code less residual per picture. Note that the whole temporal motion doesn't increase. ![]() ![]() This is due to the fact that the frames won't differ as much from each other. You are right with the following: The motion difference (as defined in ITU-R P.910, good read) between two frames of an 48 fps video will be lower than for the same video in 24 fps. Let's just assume there is no rate control and every picture is encoded with the same base QP (quantization parameter). Good question! If you have any comments or find some flaws, feel free to comment.įor any current encoder (let's take MPEG-4/AVC/h.264 as an example) frame rate does not matter as much as you think. I would love to see some real-world examples that would prove or disprove my theory. ![]()
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