Red Hat Bugzilla – Bug 88617
Graphics scale is off
Last modified: 2007-04-18 12:52:57 EDT
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20021003 Description of problem: Our company has puchased brand new Dell Precision 350 with Red Hat 8.0 pre-installed. We are told by both Dell and Red Hat that the system are certified. The video cards are ATI Radeon VE's. The problem is that the scaling of images is vertically skewed. (Meaning is I take a graphics file that is 2" x 2" in size and open it in any graphics program the actual size of the picture will be 1.875" * 2.125". Whats even worse is that digiatl photos at a resolution of 1200 * 1600 in pixels become distorted when rotated 90 degrees by almost a full inch. I am inclined to just return the machines as they are definately not certified to have this kind of problem, but I am willing to see if there is something was missed in the driver or other software. Version-Release number of selected component (if applicable): How reproducible: Always Steps to Reproduce: 1.Install red hat 8 on dell precision 350 2. 3. Actual Results: Same thing Expected Results: distorted graphics Additional info:
This problem doesn't sound like an XFree86 bug, but what it does sound like, is it sounds like your monitor or flatpanel is using non-square pixels at the resolution you have chosen. You mention a 2" by 2" graphic file, however graphics images do not have a physical size, rather they are a bitmap image of pixels of no specific size. They only take on a size when they are displayed on a screen, so I'm a bit confused. When you say "1200 * 1600" Do you really mean 1200 horizontal by 1600 vertical, or did you reverse the two numbers by mistake and mean 1600x1200? The problem you describe is unclear what specifically is the cause without more information, however if you attach your X server config file and log file, that would provide me with more information to make a more accurate hypothesis as to what is causing this problem for you. TIA
Also, is this a CRT monitor, or is it a flat panel display? Please indicate which model of either.
IT is not the monitors as we have tried several along with every possible resolution offerred for the graphics card. I was using two inches as an example. In all cases, at all sizes, if the number of pixels is equal horizontally and veritcally, the length and height are not equal on the screens. It should be easy to duplicate as we have been able to do it on several other dell's as well. They also have ati graphics cards in them.
Let me be a bit clearer. There is no indication whatsoever in this bug report with the information that you have provided, that there is an XFree86 bug occuring here that is causing the perceived problem you are experiencing. Until it can be 100% _proven_ that there is a bug in XFree86, there is absolutely nothing that I can do about it. In order to troubleshoot this problem in order to even determine wether it is caused by XFree86 at all, I require certain pieces of information. Without that information, there is nothing I can do other than close this bug report as NOTABUG as I will be unable to determine anything either way. So, please provide an answer to my questions asked above namely: 1) Is this monitor a flat panel display, or is it a CRT monitor. What model is it? 2) Attach your X server log and config file as they contain *CRITICAL* information and details as to how the software is being configured, and various other important pieces of information that I require as an absolute bare minimum to investigate this matter. Once I have that information, I can examine it and make an assessment. Without that information, I can do nothing. The only way a 100 pixel by 100 pixel image will be the exact same size when it is rotated 90 degrees on *ANY* display, is if the pixels on that display are square. If you are using a flat panel display which does not have square pixels, or if you are using a resolution on a CRT which results in non square pixels, the types of effects that you are seeing are highly probable, and it is not a bug. It is simply the result of how hardware works. In order for something measured with a ruler to be 2 inches by 2 inches on the screen, then rotated and end up being 2 inches by 2 inches still requires that your display has square pixels or that the image is being software scaled with the aspect ratio of the display in question being taken into consideration. In all cases, this has absolutely nothing to do with the video driver, X server, XFree86 at all. It is purely a function of the image manipulation software you are using doing the right thing. In such cases such software needs to be calibrated first. Those types of problems however are outside the scope of being XFree86 bugs or being related to XFree86 at all. They are also outside the scope of what bugzilla is here for, which is to track bugs, not seek technical support. So, if you now attach the information I requested above, I can investigate the data and ensure wether or not the X server is starting correctly and has reasonable startup values indicated in the log files. After investigation, if that is the case, then your problem is not an XFree86 bug, and you should seek technical support with your appropriate tech support representative. Thanks in advance.
>In all cases, at all sizes, if the number of pixels is equal >horizontally and veritcally, the length and height are not >equal on the screens. That would indicate that your monitor or flatpanel does not have square pixels. The solution would be to purchase a monitor that has square pixels. It's not an XFree86 bug if your monitor doesn't work the way that you think it should. The solution for a display with non-square pixels is to contact your hardware vendor and purchase a monitor with square pixels on it in the case of a flatpanel. Or in the case of a CRT, it would be a case of using the monitor's horizontal and vertical centering/sizing controls to stretch the display in whatever manner is required to get square pixels. Again, none of this is XFree86 related. It is completely a hardware issue, and requires an understanding of how a monitor and/or flat panel works.
In fact, I am convinced now that this is not an XFree86 problem, so there is no point tracking this any more. I'm closing this NOTABUG.