Questions tagged [whodunit]

whodunit.c, one of the assignments for Problem Set 4, will challenge you to manipulate the color value of pixels in a bitmap image in order to reveal a hidden image.

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Whodunit: Putting a name to the face

I can see the face, but I don't know who it is. Is there a web page that has all the staff faces and names on? I am doing "fall 2014" so I need the names and faces from last year (unless the person ...
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Which colours do I manipulate in whodunit pset4?

Ok, so my code is working fine - I can manipulate the colours however I want. But which colours do I change?? I've used xxd to look at common pixels, I've tried bring some out in different ...
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pset4 whodunit :how to check correctness

I followed pset4 tutorial and wrote a whodunit.c file based on copy.c but with a few lines added, then compilled whodunit and it created the exe file but when i try to run ./whodunit clue.bmp verdict....
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Trouble opening pset4 Clue.bmp

I'm having trouble opening the clue.bmp file. Every time i try to open the file to work on whodunit.c it seems to freeze gedit and i have to close the window and reopen gedit. DOes any one know What ...
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Use of check50 in pset4

I would like to test my whodunit.c that I wrote for pset4 as described here with check50. In the last psets there was always a code line for the proper call of check50 in the pset-description, like ...
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Is it even possible to isolate the colors in order to bring to the foreground “whodunit” ? [duplicate]

I have a question in psett 4's, "whodunit". Is it even possible to isolate the colors in order to bring to the foreground "whodunit" ? Because when I elimanate the red I can see a 'light bluish' ...
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Whodunit: Copy.c help

for pset 4 whodunit, when i do "cp copy.c whodunit.c" it says "cannot stat 'copy.c': No such file or directory" My directory is cd "/ home / jharvard /Dropbox /pset4"
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pset4 how to enhance the colors in the background

How do I enhance the colors in the background. I've added white colors to the image, making it much more visible, but not sure whodunit. I am trying to enhance the sky blue in the image so that I can ...
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Need help, on pset4, whodunit. I am trying to change all instances of red to white

Need help, on pset4, whodunit. I am trying to change all instances of red to white, instead of black. When I changed all instances of red to black, I was able to see a bit of the image beneath it , ...
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Why is diff showing two identical bmps different?

In the whodunit assignment, when I used the copy.c given in the pset4.zip on smiley.bmp and executed the diff check, there was no message shown. However, when I used the copy.c and diff on the clue....
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whodunit section

I've just started doing pset4. I'm stuck in whodunit section itself, I've no idea about the questions in whodunit section. After opening the file, there are list of todo's corresponding to each number ...
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whodunit Comparing colours and changing pset4

So I'm doing whodunit in pset4 and per the walkthrough by Zamyla, I should do this comparison for red so that I can change the colour. However I'm getting this error when compiling: Help please, ...
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fseek in pset4(whodunit)

everyone, this is a segment of the code from pset4(whodunit) copy.c, and I'm wondering why the function fseek is needed. Given that padding cannot be read by fread, why not just simply use fputc to ...
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What is the value of green and blue?

"If the R, G, and B values of some pixel in a BMP are, say, 0xff, 0x00, and 0x00 in hexadecimal, that pixel is purely red, as 0xff (otherwise known as 255 in decimal) implies "a lot of red," while ...
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why does the picture become “more” red in whodunit?

Inside the for loop // temporary storage RGBTRIPLE triple; // read RGB triple from infile fread(&triple, sizeof(RGBTRIPLE), 1, clue_ptr); if(triple....
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How do I resolve a `for loop initial declarations` error while compiling?

I just copied copy.c to whodunit.c. Then I saved and tried to compile the program by running make whodunit. This resulted in the following error. whodunit.c: 73:5 error: for loop initial ...
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why image color is not changing in whodunit?

I have made the below mentioned changes in my whodunit file but still the new image that is created is exactly similar to clue.bmp someone please help...
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Why is file pointer null on Whodunit and how can I fix?

(gdb) b main Breakpoint 1 at 0x804869e: file whodunit.c, line 18. (gdb) r infile outfile Starting program: /home/jharvard/Dropbox/pset5/bmp/whodunit infile outfile Breakpoint 1, main (argc=3, argv=...
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Person in pset4 whodunit

Hey guys I am doing pset4 "whodunit" of fall 2014 from cs50.harvard.edu. I successfully eliminated the red noise and enhanced other colors.I am seeing the image of someone holding something hidden ...
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1answer
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Cannot use make: “Nothing to be done for whodunit.c”

For pset5 I did as suggested and copied copy.c to a new file named whodunit.c. I've left everything the same but hopefully changed the red pixel values. When I go to compile using make I get this ...
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Pset5 - Whodunit

What do we have to do in Pset 5 : Whodunit? I know we need to analyze a file, but all I see is a lot of red pixels.
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How does fread progress through each byte in copy.c?

In copy.c (and the other apps using the same start code), how does freed know to read one byte after another? It seems to just do it automatically. Eg, this will read each byte, from first until bi....

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