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<DIV><FONT face=Verdana size=2><SPAN
class=919540221-22042008>Hi,</SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN
class=919540221-22042008></SPAN></FONT> </DIV>
<DIV><FONT face=Verdana size=2><SPAN class=919540221-22042008>I'm trying to use
my own palette for AGG as described here by
Thomas :</SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN class=919540221-22042008><A
href="http://www.nabble.com/forced-palette-and-quantization-for-RGBA-images-td14645869.html">http://www.nabble.com/forced-palette-and-quantization-for-RGBA-images-td14645869.html</A></SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN
class=919540221-22042008></SPAN></FONT> </DIV>
<DIV><FONT face=Verdana size=2><SPAN class=919540221-22042008>As explained in
the article, I'm using a typical PNG 24 bits image (produced in RGBA mode -
4 bands).</SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN class=919540221-22042008>But from this
image, </SPAN></FONT><FONT face=Verdana size=2><SPAN
class=919540221-22042008>I'm not able to produce a 8 bits PNG image with the
ALPHA, only in RGB with 3 channels - s</SPAN></FONT><FONT face=Verdana
size=2><SPAN class=919540221-22042008>ee the GDALINFO below.</SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN class=919540221-22042008>I need this 8 bits
image to generate my palette.</SPAN></FONT></DIV>
<DIV><FONT face=Verdana size=2><SPAN
class=919540221-22042008></SPAN></FONT><FONT face=Verdana size=2><SPAN
class=919540221-22042008></SPAN></FONT> </DIV>
<DIV><FONT face="Courier New" color=#0000ff size=2><SPAN
class=919540221-22042008>gdalinfo rgb.png<BR>Driver: PNG/Portable Network
Graphics<BR>Size is 1203, 813<BR>Coordinate System is `'<BR>Corner
Coordinates:<BR>Upper Left ( 0.0,
0.0)<BR>Lower Left ( 0.0, 813.0)<BR>Upper Right (
1203.0, 0.0)<BR>Lower Right ( 1203.0,
813.0)<BR>Center ( 601.5,
406.5)<BR>Band 1 Block=1203x1 Type=Byte, ColorInterp=Palette<BR> Color
Table (RGB with 256 entries)</SPAN></FONT></DIV>
<DIV><FONT face="Courier New" color=#0000ff size=2><SPAN
class=919540221-22042008> 0:
17,12,12,255<BR> 1: 27,101,44,255<BR> 2:
0,132,0,255<BR> 3: 19,130,16,255</SPAN></FONT></DIV>
<DIV><FONT color=#0000ff><FONT face=Verdana size=2><SPAN
class=919540221-22042008><FONT
color=#000000>...</FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT color=#0000ff><FONT face=Verdana size=2><SPAN
class=919540221-22042008><FONT
color=#000000></FONT></SPAN></FONT></FONT> </DIV>
<DIV><FONT color=#0000ff><FONT face=Verdana size=2><SPAN
class=919540221-22042008><FONT color=#000000>How can I generate a 8 bits
RGBA image from the original 24 bits
image ?</FONT></DIV></SPAN></FONT></FONT>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><SPAN class=919540221-22042008><FONT face=Verdana
size=2>Regards.</FONT></SPAN></DIV></FONT></DIV>
<DIV> </DIV>
<DIV class=Section1>
<P align=left><SPAN lang=FR-CA
style="COLOR: navy; FONT-FAMILY: 'Arial Black'; mso-ansi-language: FR-CA">______________________________________________________</SPAN></P>
<P><SPAN lang=FR-CA
style="COLOR: navy; FONT-FAMILY: 'Arial Black'; mso-ansi-language: FR-CA"><FONT
size=2><FONT face=Verdana><FONT size=4><STRONG>JAMES
LÉVEILLÉ<BR></STRONG></FONT>Service des systèmes de Mission<BR>Direction des
technologies de l'information<BR>Ministère des Transports du
Québec</FONT></FONT></SPAN></P>
<P><SPAN lang=FR-CA
style="COLOR: navy; FONT-FAMILY: 'Arial Black'; mso-ansi-language: FR-CA"><FONT
face=Verdana size=2>5833, boul. Pierre-Bertrand, 2ième étage<BR>Québec (Québec)
G2K 1K7<BR>Téléphone: (418) 380-2005 poste 227<BR>Télécopieur: (418)
644-6653<BR><A href="mailto:james.leveille@mtq.gouv.qc.ca"><FONT
color=#000080>james.leveille@mtq.gouv.qc.ca</FONT></A><BR></FONT></SPAN></P>
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