Hi ewavr,
I could test a few days the SX200.The ptp interface works very well for this cam. But the color of overlay display could be improved.Thatswhy I asked rudi to analyzing this problem.
Here is a chdkcam screenshot:
And this are he color palettes of the SX200 (play and record)
Here is the
Ramdump SX200 (play and record).
This has written rudi:
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we have two variants of color palettes.
At first the calculated varinat from 4x 16 byte as VUYA, you named it syspal. It is used by VxWorks- and older DryOS-cams (tested on IXUS80, A590, A610, A620, A710, A720).
The maincolors are diagonal arranged.
transparent-byte:
I found $FF > $7F(or $80),$3F > $00 (full transparent > middle > not transparent)
luminance-byte:
This value are never over $E0. This is 7/8 from a byte value. So I have a different calculation routine. Please try it.
my favorite calculation routine:
y:=(c1.Y+c2.Y)div 2;
y:=y*8 div 7;
if y>$ff then y:=$ff;
c.Y:=y;
c.U:=(c1.U+c2.U) div 2;
c.V:=(c1.V+c2.V) div 2;
c.A:=(c1.A+c2.A) div 2;
At second a full palette variant with 4x 256 byte as AYUV. It is used by newer DryOS-Cams (tested on SX200).
In this case the colors are in a line arranged.
transparent-byte:
found $03 > $02,$01 > $00 (full transparent > middle > not transparent)
my routine to adapt:
case c.A of
01: c.A:=$3f;
02: c.A:=$7f;
03: c.A:=$ff;
else c.A:=$00;
end;
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For color arrange see CHDK palette viewer.
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I have written a
ColorTab-Viewer.
You can open extracted color tables with 64 or 1024 byte, a RAM-Dump or a firmware-dump (PRIMARY.BIN). I found only on DryOs-firmware build-in color tables.
On RAM-Dumps the program looks-up for pointer address to color table (displayed only the first found address), look at status bar.
To idendify colortables: first color must be a full transparent color and last color must be black without transparency.
You can change the color decoder routine for calculated color tables in menu "decoder".
Also you have a preview function by mouse-over in color field (tranparent colors have a gray frame all other a black frame). The preview area on left side show additional color information and under it is a sorted color list.
rudi
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Maybe you can use this knowledge to improve the overlay colors in chdkcam.
msl