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On 03/09/2010 05:15 AM, stef wrote:
<blockquote cite="mid:201003090615.54262.stef.dev@free.fr" type="cite">
<pre wrap="">Le lundi 8 mars 2010 17:20:23 Chris Berry, vous avez écrit :
</pre>
<blockquote type="cite">
<pre wrap="">Ok Stef I have a bit more time to concentrate on this at the minute. I
have updated the white_shading.pnm and included it at
<a class="moz-txt-link-freetext" href="http://sites.google.com/site/bez625/updates-1/update080310">http://sites.google.com/site/bez625/updates-1/update080310</a> there is also
a copy of the latest scan there too. I only have 20 shading lines in the
shading area because there is a lot of blue in that area. Should I widen
it (more shading lines) or should those blue areas be included?
Also how do I disable the averaging? Is it a software thing or is it on
one of the registers? I'm also not too sure what you mean about the
offset, is it the DAC offset?
Thanks
Chris
</pre>
</blockquote>
<pre wrap=""> Hello,
the white shading picture must be all white. The picture you posted is mostly
OK, but there is still some blue on the right. This is not a blocker, but it
will certainly have to be fixed to reach best image quality.
By averaging, I was thinking of the AVEENB bit of register 3 which tells the
ASIC to delete extra data points or average them to produce data from higher
dpi.
Regards,
Stef
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style="border-collapse: separate; color: rgb(0, 0, 0); font-family: 'Times New Roman'; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; font-size: medium;"><span
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style="color: rgb(68, 68, 68); font-family: Arial,Verdana,sans-serif; font-size: 13px; line-height: 20px; text-align: left;">Hey
guys,<br>
<br>
I have experimented with disabling average and altering the offset as
Stef suggested. Disabling averaging seems to make things worse (dark
and light lines where solid colour appears with AVEENB) and changing
the offset seems to make no real difference so i'm not sure what is
happening. Also I am unsure about what target code I should use for the
shading compute_coefficients (assumed 0xdc00 as it seems popular).<br>
<br>
At the project site (update ) there are a few images in a bzip file to
show what I mean about toggling the AVEENB. It certainly seems better
to have it on but this might just be misleading images.<br>
<br>
The main issue now seems to be the different coloured vertical lines
down the document. In addition I performed higer dpi scans (300, 600)
and the whole image seems darker and the vertical lines are more
prominent, i cant say im entirely sure whats causing them but im
guessing its the shading function.<br>
<div><br>
</div>
<div>I have also attached my source on the project update if this will
make it easier to advise on what im doing wrong. I will get around to
tidying up my code soon so i can commit to git without it looking
messy. Has there been anymore information about a next release date? I
have been skimming the mailing list and not seen anything mentioned.<br>
<br>
Thanks<br>
<br>
Chris<br>
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