Bitmap Image Processing Homework: Header Extraction and Pixel Information Manipulation
This project involves extracting bitmap file headers, creating histograms, and defining regions of interest based on specified coordinates in image pixel data. The assignment includes grading criteria and a report submission component.
Bitmap Image Processing Homework: Header Extraction and Pixel Information Manipulation
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Presentation Transcript
Digital Image Processing #HW1 Extraction of Bitmap Header File Manipulation of Image Pixel Information Contact Information Tzu-Jui Wang (王子睿) Visual Communications Lab Dep. of Communications Engineering, National Central University No.300, JhongdaRd., JhongliCity, TaoyuanCounty 32001, Taiwan (R.O.C.) Phone: +886958801691 E-mail: juliuswang0728@gmail.com
Outline • Reference • Work Flow • Introduction to Bitmap File • Homework Details • Extract Header File • Construct Histogram • Extract Region of Interest with Specified Coordinate Set • Grading Policy • Demo Schedule
Reference • A Beginners Guide To Bitmaps, • http://local.wasp.uwa.edu.au/~pbourke/dataformats/bitmaps/ • http://atlc.sourceforge.net/bmp.html • Data type in Computer, wiki resources, • http://en.wikipedia.org/wiki/Integer_(computer_science) Those might be useful !
Work Flow Input coordinate set (xi, yi), i=1,..,4 of bounding box 24-bit 8-bit Extract header information Extract region of interest Extract pixel information (x1,y1) (x2,y2) Construct histogram on R, G, B channels, respectively (x3,y4) (x4,y4)
Introduction to Bitmap File (1/2) File header (14 bytes) Header file (Image profile) Info header (50 bytes) Empty for 24-bit image i.e. a 8-bit image, N = 28 Pixel information Image content
Introduction to Bitmap File (2/2) 54 bytes + 1024 bytes Header + Color palette Header 54 bytes Image content Image content 24-bit lena.bmp 8-bit lena.bmp
Construct Histogram • Histogram on R, G, B channels Pixel value Frequency Figure1: beatles.bmp Figure2: RGB histogram
Extract Region of Interest with Specified Coordinate Set • Suppose given (x1, y1), (x2, y2), (x3, y3), (x4, y4) • The bounding box will be as followed (x1,y1) (x2,y2) Final output (x4,y4) (x3,y3) Bounding box
Grading Policy – Code & Demo (80%) • Everyone will be asked few questions. • Extract Header File (20%) • We’ll test your system with images except lovely Lena. • Construct Histogram (30%) • Same as the above. • Extract Region of Interest with Specified Coordinate Set (30%) • Arbitrarily give four coordinates, and create a new bitmap file with extracted region.
Grading Policy – Report (20%) • Report (20%) • Plot all your experimental results. (10%) • Depict the .bmp format as clear as possible. (5%) • Describe your findings as rich as possible. (5%) • We don’t force you to write down how you feel about this homework. But, you can still show it up. • Too trivial, too hard, …too ? • You can describe any difficulty you’ve encountered.
Demo Time • Demo time will be at 2010.10.07, begin around 7:00 pm (2 weeks later) at R3-307 (VCLab). • Demo orders will be announced later, 5 minutes for each, please refer TA’s website. • http://140.115.156.251/vclab/html/course/DIP2010.html • Bring your codes and report. • No delay is allowed except a special cause.