[Bf-committers] patch #21750: Vectorscope and luma/color waveform for image view

Xavier Thomas xavier.thomas.1980 at gmail.com
Fri Mar 26 02:44:17 CET 2010

2010/3/25 Paolo Ciccone <phciccone at gmail.com>:
> Xavier, that looks very promising. For the VScope, would it be possible to
> to have more clear demarcation of each color area? It would be also helpful
> to have the standard line for the skin tone, the single most important
> feature of a VScope.

For now I reproduce the look of the sequencer scopes but it is easily
changeable. Better grid and the ability to zoom is on my todo

Lastly, VScopes usually have a marker of some sort,
> like a square that shows the limit of the usable range for each color.
> Basically, when calibrating a monitor or a camera with a DSC chart your R,
> G, B, M, C, Y would optimally "fall" within those squares. Beyond those the
> colors start getting oversaturated. Here is an example of what I mean:
> http://paolociccone.com/TrueColor-HD250-part2.html
In fact the corners of the exagon have similar representation to those
squares. In the picture you linked, if you connect the squares with a
line which color blends  between the color the squares correspond to
(R Mg B Cy G Yl) -> you got the hexagon which serves as grid in my
patch and in the sequencer scopes.

Some things that might be cleared up:
-The aspect is changed for the hexagon not be squashed -> it should be
but I keep it for consistency with the sequencer
-the coordinates of each points correspond to the U V chrominance
(like in the sequencer) but I think it is more common to represent the
chromimance using Cb Cr coodinate systems.

> Excellent work!
> Paolo Ciccone



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