1 / 11

Digital Image Processing HW1

Digital Image Processing HW1. Yi-Chun Wei Visual Communications Lab National Central University Mar . 2, 2012 . Outline. Work Chart Introduction to Bitmap File Homework Details - Construct color histogram - Color image transform to gray-level image - Resize the image Grading

lulu
Download Presentation

Digital Image Processing HW1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Digital Image ProcessingHW1 Yi-Chun Wei Visual Communications Lab National Central University Mar. 2, 2012

  2. Outline • Work Chart • Introduction to Bitmap File • Homework Details - Construct color histogram - Color image transform to gray-level image - Resize the image • Grading • Demo Schedule • References

  3. Work Chart Extract header information Extract pixel information Transform to gray-level image 512*512 Construct the histogram on Y Channel HW1-1 512*512 Resize image HW1-2 640*480

  4. Introduction to Bitmap File(1/2) • Header file • - File header (14 bytes) • - Info header (54 bytes) • Color table • - ex: a 8 bit image, • N=28 • Image content • - Bit array • (pixel information) Y. C. Dong, “Digital Image Processing HW1”, 2009

  5. Introduction to Bitmap File(2/2) Scale: 512*512 Scale: 512*512 Header + Color palette 54 bytes + 1024 bytes 54 bytes Header Image content Image content 8-bit Lena 24-bit Lena Y. C. Dong, “Digital Image Processing HW1”, 2009

  6. Color Image Transform to Gray-Level Image  Y = 0.299R + 0.587G + 0.114B 8-bit Lena 24-bit Lena

  7. Gray-levelHistogram Blue Gray level 196 ? Green 122 Red 83 Y histogram number Gray level pixel value

  8. Resize Image Bilinear Interpolation: • P: Desired Point • Q: Known Points • (four closet pixels) • R: Point on the line with known points Z = AX + BY + CXY+ D Gray level value known points Where A, B, C and D are obtained from the gray-level of the four neighbors. J. Nett,”Bilinear Interpolation”, 2009.

  9. Grading • Demo Code (80%) - Extract header file (20%) - Color image transform to gray-level image (20%) - Construct color histogram (20%) - Resize image to 640*480 (20%) • Report(20%) - Plot all your experimental results. (10%) - Describe your finding as rich as possible. (10%)

  10. Demo Schedule • Thursday night, March , 2012. - Begin around at 19:00 at R3-307.(VCLab) • NOTE: • We will use another image to test your code. • The details will be announced on our course website. ( http://140.115.156.251/vclab/html/course/DIP2012.html )

  11. References • Lena 24-bit color image, 512*512 http://www.indinf.pub.ro/catalinp/proiect/lena512.bmp • About Bmp format website http://en.wikipedia.org/wiki/BMP_file_format(wiki) http://crazycat1130.pixnet.net/blog/post/1345538-%E9%BB%9E%E9%99%A3%E5%9C%96%EF%BC%88bitmap%EF%BC%89%E6%AA%94%E6%A1%88%E6%A0%BC%E5%BC%8F

More Related