On 24.03.2013 21:09, Leonardo M. Ramé wrote:
On 2013-03-24 20:44:50 +0100, Sven Barth wrote:
On 24.03.2013 20:39, Leonardo M. Ramé wrote:
Now your lBufSize contains the number of pixels, so only Inc(I, 1)
should be correct. And for copying all data at once you now need to
use "lBufSize * SizeOf(Word)" instead. And the for-loop variant
would look like this:
=== code begin ===
for i := 0 to lBufSize - 1 do
lStream.Write(lBuffer[i], SizeOf(Word));
// or
lStream.WriteWord(lBuffer[i]);
=== code end ===
Yes, the code looks correct, but it still creates the wrong resulting
image.
If you look at the attachment, the upper image is the result of your
last suggestion, while the lower image was created using the while loop
I've shown.
I'll re-check my drawing function, maybe your code is correct and the
problem is on that function.
I just noticed that you are still using "SizeOf(PWord)" in your
lStream.Write. This is wrong. You want to copy one Word element
(SizeOf(Word)=2) instead of two/four (depending on 32 vs 64 bit
SizeOf(PWord) is either 4 or 8). Which is also why your Inc(..., 2)
works as you are copying multiple entries at once.
Well, this is funny, after re-checking the code, I noted it works if I
use this:
(1) for I := 0 to lBufSize - 1 do
lUnCompressed.Write(lTmpBuff[i], SizeOf(PWord));
But, using SizeOf(Word) doesn't:
(2) for I := 0 to lBufSize - 1 do
lUnCompressed.Write(lTmpBuff[i], SizeOf(Word));
What I would like to achieve is this:
(3) lUnCompressed.WriteBuffer(lTmpBuff^, lBufSize * SizeOf(Word));
But using this, I get the same result of (2).
Maybe your problem is indeed in your drawing function. Because the
usage of SizeOf(PWord) is definitely wrong if your lBuffer basically
contains Word sized pixels after each other. You should currently
even get different results depending on whether the application is
32 or 64 bit.
Regards,
Sven
Sven, I can confirm the image display function was wrong. Now I can
write all data to the stream at once!.
Nice to hear that you found the final problem as well :)
Regards,
Sven
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