Topics

resolution

Guy Martin <agm@...>
 

I may have missed the discussion about this but when animating HRV, as the terminator moves across and the pictures descends into darkness the resolution goes to 'pot', square edged chunks of dark grey and black. I can see this effect on some of the LRIT images as well. Is this an effect of the lossy compression or the fact that graphics cards only use 8 bits even for a greyscale.

regards, Guy

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David J Taylor
 

--- In MSG-1@..., "Guy Martin" <agm@t...> wrote:
I may have missed the discussion about this but when animating
HRV, as the terminator moves across and the pictures descends into
darkness the resolution goes to 'pot', square edged chunks of dark
grey and black. I can see this effect on some of the LRIT images as
well. Is this an effect of the lossy compression or the fact that
graphics cards only use 8 bits even for a greyscale.

Guy,

Both LRIT and HRV normally use lossy JPEG compression. This may
account for the artefacts you are seeing. See my post on HRV.

Cheers,
David