I'm trying to use a listview component to show all the fonts on my system, and display each item (row) in the actual font design.
When I run the following code, nothing displays in the listview.
If I rem out line 4, then the list populates with all the fonts, but of course, in the default listview font.
I thought I read somewhere that each item in a listview can be set to a different font.
int i = 0; foreach (FontFamily oneFontFamily in FontFamily.Families) { listView1.Items[i].Font = new Font(oneFontFamily, 10); listView1.Items.Add(oneFontFamily.Name); i++; }
I am working on image processing in C + + and opencv, I treat images in grayscale, ie the pixel values it must be between 0 (black) to 255 (white).
Mat img; img = imread (file, -1); for ( int i = 0; i < img. rows ; i ++) { for ( int j = 0; j < img. cols ; j ++) { val_pixel=img.at < double >(i,j); printf( "%d ",val_pixel); } printf( " "); }
when displaying the pixel value from two loop, I get values to 0 and it is normal for propablement black areas, but for whites I find the value -2147483648. I don't understand why this value is not 255.Is there an explanation for this has value.
I have an image of size 640x480 pixels. It's possible to obtain the dimension in mm of one pixel from that image given only that size?I do not have the size of the image in mm,however.
I wrote a script that generates n random pixel positions and draws them to the screen. Works well. Now i tried to rotate them. Rotating does work too. But it does not work as i planned it.
paramters 'angle' and 'timestep' work somehow, but not as they should do. the function 'move' is supposed to rotate the pixelfield 'angle' degrees in a given direction, addicted to the 'timestep' parameter. 'timestep' is needed time for drawing in one single game loop.
rotation point is the middle of the screen. when i set angle to 10 it should rotate 10 degrees / second. Instead it's rotating very very fast and all stars are moving nearer to the center of the screen, so after x rounds there is just 1 pixel left in the middle of the screen. there is a kind of gravition.I'm working with SDL2. What I did find out:
FPS is <= 60, 'cause of the 'SDL_RENDERER_PRESENTVSYNC' flag. When i skip that flag, for any reason the 'gravition' would take more time. FPS is <= 1400 then, 'though i got a natural game loop (i hope):
Im new to c#. In c++ I have made a window and painted it with dots and concentric circles, like a radar PPI screen. Trying to do this in c#, I can't find how to draw a single pixel on the window.
Also, what should I be drawing on: the form, panel, picturebox...?
I would like to subtract one image from another to get something like "differential picture" (i am not sure whether the name is correct). I've managed to read the FILEHEADER and FILEINFOHEADER of bitmap. I will subtract 24-bit bmp files only. However i can't understand the structure of this file. So far my code looks like this. Any example of at least copying one bmp file to a new one? This example would be useful, because subtracting will be simillar, instead of copying the pixel value i will just put abs(value1-value2) in the output.
Code:
// ConsoleApplication1.cpp : Defines the entry point for the console application. #include "stdafx.h" #include <iostream> #include <fstream> using namespace std; struct BITMAPfileHEADER {
//Casting a void pointer pointing to an array of memory locations(the pixels), to a pointer to an array of Uint8's. //SDL_MapRGB() Returns an Uint32 containing the color 0,0,255,(0/255, i think it returns the transparency too, or else it would rather return a Uint24,not sure).
Then modifying the memory location, in this case the pixel at the middle of the window.
What i seem to not understand is that, i cast pixels to Uint8*, which means I now have a pointer to an array of 8bit numbers, but SDL_MapRGB seemingly returns an Uint32 or Uint24 for a color composed of r,g,b, together without 'a' is 24bits(256=1b,256=1b,256=1b)=3b.
And then i somehow assign that pixel which is of 8bit at chosen location, an Uint24 or 32bit unsigned int.
I'm currently working with linear VRAM (a buffer with 256KB memory, divided into four 64k planes, so plane 0 at 0x00000, plane 1 at 0x10000, plane 2 at 0x20000, plane 3 at 0x30000). Just add the index of the plane to that for the full address in VRAM.
I'm still wondering how to get a specific pixel from VRAM (x,y coordinate) when doing graphic modes (none color modes work, only the black/white pixels (1-bit) graphic mode works).
how I can get specific pixels from the VGA VRAM (having linear access described above) using Shift Register Interleave mode (VGA modes 4&5), 16-bit planar mode (Most VGA modes) etc.
I have managed to successfully extracted the BMP file header and file info but ran into troubles with getting the pixel data out into a 2d array.This is my function to read the data while i have another to write the data. The output does not match the input at all.
void BMPProgram::GetPixelData(std::ifstream & inStream) { std::cout << "Entered function"; if(inStream.fail()) return; //space allocated to reading in of padding int paddingSpace = 0;
[Code] ....
PIXEL is a struct of 3 unsigned char containing values of RGB.
I'm trying to read a jpeg pixel and then compare it if it'x bigger than a number to change it. Either I'm breaking the folder if I start less than 22000 which is very large number shouldn't include the header or I'm getting solid color without any different.
The doubt is. I have a test_xpm function and I need to call this char array but this is so many pointers that I can't even figure out where I'm pointed to (?)
Code: int test_xpm(unsigned short xi, unsigned short yi, char *xpm[])
I tried something like read_xpm(xi, yi, *xpm[0]); but I'm guessing I need to index that array and run all those chars in order to show them.
I dont even know where to start. I spend the last 7h infront of my computer and i'm so frustrated cause my professor gave us no information what so ever. At the moment its more of a trial and error process than anything else.
How would i set the color of an individual pixel for examplel or how would i save the file ?
I need to save RGB values of each pixel in a 3D array A[width][height][3]. I found a code online that transfers the bytes into an array but I cant understand how bytes are saved them so i could transfer them into an array. The truth is I dont know much about working with images at all so i have a problem working on them. How to transfer the RGB data from an .jpeg image into a 3D array? This is my code so far:
#include <iostream> #include <jerror.h> #include <jpeglib.h> using namespace std; int main(){ FILE *pic = fopen( "image.jpeg", "rb+" );
i wish to plot a mathematical function on a 2-dimensional grid. The function will be represented by 3 sets of floats, x-values, y-values, and z-values. Obviously, it is impossible to plot 3 such data sets on a 2D grid, so one approach is to use pixel coloration to represent the z-values.
Those examples (and there are many to be found) show something like the function of the complex variable z, f(z) = exp(z). I have attached a exp(z).jpg example of the imaginary part of the plot exp(z).
My question is: How to accomplish such a gradient colorization, assuming one already has the data?
I have experimented with Gdiplus SetPixel, but I have not figured out how to produce a smooth gradient.
I'm trying to blur a ppm image by averaging the components of the color(r, g, b) within a certain reach of a specific pixel. This is a picture and description:
In this diagram, we are trying to compute the color for the pixel in the center (the red element). Its neighbors (within a reach of 4) are all of the green elements. The pixels outside of this 9x9 square are not considered in the blurring calculation for this pixel. To compute the color for the center pixel, average the red, green, and blue components (independently) of every pixel in the 9x9 square (including the pixel itself; the red element in this diagram).
I have some code, but it is not working correctly. The function "computed_color" on line 52 is shown in the next block of code.
I am building a program that will read from a particular web page. I have written it so that it will parse the page correctly, but I can only do it for a downloaded page right now. I would like for it to work simply with the URL.
I have seen things about "screen scraping", though I don't quite understand what it does - I think it's more for just parsing it, which I can already do.
If it is possible to automatically download that file, that is fine as well.
If it matters at all, the pages I am reading from are stories on Fanfiction.net.