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The next Foveon camera?

Started 2 months ago | Discussions thread
xpatUSA
xpatUSA Forum Pro • Posts: 23,016
Re: The next Foveon camera?

tarmov wrote:

Doppler9000 wrote:

How do you compute the compression ratio?

That Canon has a 45MP sensor that outputs 24-bit jpeg with 45MP resolution.

And that jpeg image had about 35MB worth of data.

3*45 % 35 = 135 % 35 =~ 3.7x compression ratio

Sigma DP2m has a 15MP horizontal sensor that outputs 24-bit jpeg with 15MP resolution.

I claimed an average DP2m jpeg file size of 20MB.

3*15 % 20 = 45 % 20 =~ 2.2x compression ratio

You could also divide the file size with the amount of horizontal pixels.

That Canon had a 35MB jpeg file from a horizontal 45MP sensor. Essentially 0,8 bytes per horizontal pixel.

Sigma DP2m on average has about 20MB jpeg files from a horizontal 15MP sensor. essentially 1,3 bytes per horizontal pixel.

-Tarmo

There's also 'JPEGsnoop' which calculates it for you ...

https://www.impulseadventure.com/photo/jpeg-snoop.html

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