![]() ![]() So, back to the "It will vary dramatically depending on the content of the source videos" comment: The compression ratio you'll see, and the resulting quality, will depend significantly upon: It is all wildly more complex than that, with zillions of different approaches, techniques and algorithms within specific CODECs and between CODECs to make this happen. So, instead of having to store information about every single pixel in a frame, the CODEC just says "x1, y1 to x2, y2 are all color x". Example: Lossy blocks: If all but one pixel in an area is the same color, the CODEC 'loses' the one pixel. They do not reproduce a pixel-by-pixel, frame-by-frame exact duplicate of the original source video. H.264 is " lossy", as are many other CODECs.These frames generally make up the vast majority (80%-99%) of frames in a video. Intra-frames: a description of changes to the previous frame.Key Frames: a full rendering of the entire video image. ![]() Instead there are two types which are colloquially referred to as Not every video frame data structure in an common H.264 (or other CODECs for that matter) is a full image. ![]() How is this possible? A simplified answer: There are a couple of techniques and facts about video compression that make this possible: Maybe 768kbps if you are really interested in quality. 512kbps is very reasonable and arguably standard. I'll get to that in a bit.Ħ40x360 is not that large. It will vary dramatically depending on the content of the source videos. I've looked everywhere, and nothing gives me any kind of expected compression. I'm just looking for a rough outer guide for quality, like "more than 500x compression is crazy" or "less than 400x is a waste of bandwidth". That seems insane - more than 530:1 compression? That's 99.8% compression. I've been told that, for that file, 500 Kbits/second (or 62 KB/s) is not an unreasonable video bitrate. Generally speaking, what kind of compression ratio should I be expecting to see (while staying within a reasonable level of quality)?įor example, a 640x360 (16:9) pixel video file 24 frames per second and 16-bit color should yield an uncompressed file that is approximately 33 MB/s. We are trying to create multiple bitrate profiles in order to accommodate streaming across internet connections, processors, devices, etc. I'm about to undertake a large video encoding project using H.264 encoding. Note bene: I realize this is an immensely complicated question with about a million levels of nuance that I'm trying to reduce to a single number. ![]()
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