PDA

View Full Version : why dots appears in image?



selvanathan
October 14, 2008, 13:43:09
Dear Sir,
I have attached 2 images taken with same Camera, same lens,same lightings, same focal length, same properties(default properties) and.....

only the difference is UYVY.Jpg is taken with UYVY(1204x768) Video Format and Y800.Jpg is taken with Y800(1024x768) Video Format.....

Kindly refer the images.... in UYVY video format image is clear but in the Y800 Video format there are so many dots (or boxes) appeared...... what is that?? when processing the image, it distrubs me highly.... how to avoid this...

problem nicely viewed inside yellow marked place....
Images saved with Bmp format is also having same problem....

thanks in advance..

Stefan Geissler
October 14, 2008, 14:26:37
Hello Selvanathan,

if the camera runs with the Y800 video format, you will receive the raw data provided from the CCD. It is the Bayer Mosaic pattern, what is displayed. Depending on the lighting conditions, you see the red, blue and green pattern. If there is less blue light, then these pixels are all dark / black.

For more information, please refer to http://www.theimagingsource.com/en/resources/whitepapers/download/howcolcamswp.en.pdf

selvanathan
October 15, 2008, 04:58:28
Dear Stefan,
Thank u for your reply... now i under stood.... and is there any other method to use Y800 video format images with out disturbance with normal lightings....

thanks in advance

Stefan Geissler
October 15, 2008, 13:57:28
Selvanathan,

yes, there is. Use a color format as "BY8" or "UYVY" and set the sink color format to "Y800". Then you will receive a nice gray scale image.

Alternatively you may think of using a monochrome (DMK) camera model instead of a color model.

selvanathan
October 15, 2008, 15:57:58
Dear Stefan,
I attached my source code for your reference.... kindly refer that and tell me where i need to give sink color format to "Y800"....

thanks in advance...

Stefan Geissler
October 16, 2008, 12:23:37
Hi Selvanathan,

It is "live_dlg.cpp" line 18:

#define PIXEL_FORMAT eRGB32
exchange against

#define PIXEL_FORMAT eY800

selvanathan
October 20, 2008, 05:15:43
Dear Stephan,
Thank u for u r valuable reply......

selvanathan
October 20, 2008, 08:30:13
Dear Stefan,
i change pixel format from #define PIXEL_FORMAT eRGB32 to #define PIXEL_FORMAT eY800 but it not display anything in the window....

Stefan Geissler
October 20, 2008, 09:27:11
Hello Selvanathan,

The problem is, "StretchDIBits()" can not copy the Y800 image buffer. Thus you see no image. I suggest to use a DMK if monochrome image are needed and use the eRGB24 pixel format. I know, this is not a good solution.

What do you plan to do with your program? If you do not want to talk about this in public, you may contact me at following link: http://www.imagingcontrol.com/en_US/support/case/

selvanathan
October 20, 2008, 11:16:46
Dear Stefan,
Thanku for u r reply... its not a problem to discuss in public... my exact requirement is.... i need to give two solution in a single project with single camera ...

For following two solutions,,,, camera position, focul length,... are not changed.. just i give two options for user to select solutions...

For Solution 1:

i need...

1. UYVY(1024x768)
2. 15 FPS

For Solution 2:

i need...

1. Y800(1024x768)
2. 30 FPS

Also i attached my sample project for your kind reference.... plz do need ful...

selvanathan
October 30, 2008, 11:39:58
Dear Stefan,
i am waiting for u r reply for a long time....

Stefan Geissler
October 30, 2008, 16:01:27
Selvanathan,

I got your sample code on 20.10. and did something with it. But I do not remeber what.

I think, the main problem was, StretchDIBits wont copy Y800 images, right?

selvanathan
October 31, 2008, 03:05:28
Dear Stefan...

Thanku for u r reply... your are right.... please help me to solve following solutions in a single camera

For following two solutions,,,, camera position, focul length,... are not changed.. just i give two options for user to select solutions...

For Solution 1:

i need...

1. UYVY(1024x768)
2. 15 FPS

For Solution 2:

i need...

1. Y800(1024x768)
2. 30 FPS

Also i attached my sample project again for your kind reference....
plz help..... thanks in advance

Stefan Geissler
October 31, 2008, 08:30:40
Hello Selvanathan,

Please contact me at http://www.imagingcontrol.com/en_US/support/case/. This avoids discuss your problem in public and makes thinks easier for me. (I can ask for more details.)

Thank you in advance

petertparker
November 5, 2008, 19:15:21
Hi selvanathan

What is the meaning of

1. UYVY(1024x768)
2. 15 FPS

3. Y800(1024x768)
4. 30 FPS

selvanathan
November 6, 2008, 06:42:05
hello petertparker...

UYVY(1024x768),Y800(1024x768) are Video formats... 1024x768 is Width and Height of camera.... UYVY displays colour image.. Y800 displays monocrome image..

15,30 FPS are Frames per second...