Errors in Writing JPG Images / strange colorization / image quality
Author: Ben_Zurich
Creation Date: 4/7/2015 3:53 AM
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Ben_Zurich

#1
Problem:
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We have occasional, unreproducable errors when writing certain pictures (written into JPG format) from running a mass batch processing routine on Wealth-Lab (see attached images).


Background
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We are running our “WL Production” machine on a Win Pro 7 64 bit, based on a VM Ware Virtual Machine.
The virtual machine setup has been chosen because it enables us to access the 10’000s of data series directly via a Virtual Machine Network with our Server, which runs on the same Hardware (as a Virtual Machine). This hardware “co-location” of machines was necessary because we had many thread aborts when running it over normal Ethernet networks. Now the number of thread aborts has been strongly reduced (but not completely eliminated).


Virtual Machine Configuration:
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Windows 7 Professional 64 bit

Memory: 10’240 MB

“Video Card:”
• Number of Displays: 2
• Total Video Memory: 128 MB
• Enable 3D Support: Yes

On this machine, we run a batch processing routine with Auto-It .
It runs a batch with about 250 graphs with various indicators, processing 1000s of external symbol watchlists, etc etc.
No other tasks or users operate on this virtual machine, it is reserved for producing this batch.


Questions:
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1) Do you have any idea how graphic errors like the ones in the attached images could happen and/or prevented or in which “direction” we could search for solutions?
2) Requirements of WL6 regarding Graphics card / RAM and could this possibly be a source of such a problem?
Could this pose any problem at all when not displaying the image on a screen (the Virtual machine is only accessed for control purposes via a remote desktop and can round “blind”), but just writing it?
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Cone

#2
I think you missed attaching the images.

Anyway, how does the batch process work?
I assume that the AutoIT script successively opens a Strategy that includes GetChartBitmap() and then calls Bitmap.Save().
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Ben_Zurich

#3
Here are a few images..
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Eugene

#4
1) Have you tried different, uncompressed output format like BMP instead of JPG?
How about I think the problem may be related to the previous issue you were having: thread safety?
Does your code set sufficient timeouts?

2) Are you sure all your components are free from faults (graphic card, RAM, HDD)?
To exclude a VM software bug, have you tried executing an AutoIT script of the same scale with a different program (i.e. not Wealth-Lab)?
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Cone

#5
Like Eugene, it strikes me as an image quality issue.

I worked out an example that follows the instruction How to: Set JPEG Compression Level

CODE:
Please log in to see this code.
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Ben_Zurich

#6
We haven't had time yet to revisit / go through your suggestions,

but funny enough, today we had this error - here the image is OK, but the "charting elements" (trendlines, fibo etc) are misplaced in time!
(all trendlines and the fibo retrace element are about 1.5 years misplaced to the left)

So far this was unique - never happened before.




Upon a second batch write process this image was written correctly again - error disappeared!
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