How does a video codec work?

Re:How does a video codec work? by lightedman on Saturday November 23, 2019 @03:38PM (#21616373)

278GB is a bit off. The real number is higher than that, but not by too much more, but they definitely messed up on their math somewhere. 1280 horizontal pixels times 720 vertical pixels times 8 bits per pixel color channel times 3 color channels (RGB) times 30 FPS times 60 SPM (sec per min) times 60 MPH (min per hour) divided by 8 bits to convert bits to bytes and finally divided by 1,024 bytes per kilobyte gives 291,600,000KB, exactly 291.6GB.

And now days, that kind of uncompressed video is more than feasible, at least in countries with developed gigabit internet capability, as you'd need just 634mbit of bandwidth to handle an uncompressed 720p stream at 30 FPS. Local storage on even first-gen SATA drives can hit double+ that.

Storage itself? Well, we've got the cloud, right? /s

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Re:How does a video codec work? by EvanAnderson on Saturday November 23, 2019 @04:19PM (#21616626)

You're mixing Si units and IEC units[1]. The article's measurement of 278 GB (sic) is really 278 GiB.

1280 horizontal resolution x 720 vertical resolution x 3 8-bit bytes per pixel x 30 frames per second x 3600 seconds per hour is 298,598,400,000 bytes per hour. 1GiB (1,024 bytes x 1,024 KiB x 1,024 MiB) is 1,073,741,824 bytes. Dividing that out gives ~278.09 GiB.

[1] https://en.wikipedia.org/wiki/Binary_prefix

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Re:How does a video codec work? by lightedman on Sunday November 24, 2019 @12:24PM (#21621829)

I'm responding directly to the GB claim. I'm very well-aware of binary prefix (in fact several of my other online names are those very words) and the general industry-wide mix-up that is used on the common consumer is to start with KiB and then just run that in plain units of 1,000 for MB and GB, which is what I went with.

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