Just a stranger trying things.

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  • 81 Comments
Joined 1 year ago
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Cake day: July 16th, 2023

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  • My number one gripe with organic maps is how fragile the search is. If you don’t write it exactly right, you get no or irrelevant results. Also, it seems to have no clue of what is popular and what people expect when they search for something. I’m not talking about personalized results but for example the following: searching for “Eiffel”, leads me to minor roads, restaurants and all kinds of results unrelated to the Eiffel tower. This is what is troubling me the most.


  • Exactly, this is about compression. Just imagine a full HD image, 1920x1080, with 8 bits of colors for each of the 3 RGB channels. That would lead to 1920x1080x8x3 = 49 766 400 bits, or roughly 50Mb (or roughly 6MB). This is uncompressed. Now imagine a video, at 24 frames per second (typical for movies), that’s almost 1200 Mb/second. For a 1h30 movie, that would be an immense amount of storage, just compute it :)

    To solve this, movies are compressed (encoded). There are two types, lossless (where the information is exact and no quality loss is resulted) and lossy (where quality is degraded). It is common to use lossy compression because it is what leads to the most storage savings. For a given compression algorithms, the less bandwidth you allow the algorithm, the more it has to sacrifice video quality to meet your requirements. And this is what bitrate is referring to.

    Of note: different compression algorithms are more or less effective at storing data within the same file size. AV1 for instance, will allow for significantly higher video quality than h264, at the same file size (or bitrate).