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ASCII art with C#

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30 Jan 2005CPOL1 min read 453K   9.6K   189   53
About writing an image to ASCII converter.

Sample Image - ascii_art_with_c_.jpg

Introduction

Behind the scenes: I like C# and I like ASCII art. So I asked myself if somebody has written some image to ASCII application in C#. I Googled but found nothing. I did image manipulation stuff for my company and so I decided to build a basic image-to-ASCII conversion library in C#.

Step 1: The Upload Form.

To keep it quite simple, I just check the content type and let my library do the rest.

C#
if(File1.PostedFile.ContentType=="image/gif" ||
    File1.PostedFile.ContentType=="image/jpg" ||
    File1.PostedFile.ContentType=="image/jpeg" ||
    File1.PostedFile.ContentType=="image/pjpeg" ||
    File1.PostedFile.ContentType=="image/bmp")
   {
        Output.Text = "<xmp>" +
        StaticDust.AsciiArt.ConvertImage(
         File1.PostedFile.InputStream) +
        "</xmp>";
   }
   else
   {
        ...

Step 2: The Library

The first thing I do is of course load the image:

C#
Image _img = Image.FromStream(stream);
Bitmap _image = 
 new Bitmap(_img, new Size(_img.Width, _img.Height));
_img.Dispose();

Next I grayscale the image - you'll see later why.

C#
Rectangle bounds = 
 new Rectangle(0, 0, _image.Width, _image.Height);

ColorMatrix _matrix = new ColorMatrix();
_matrix[0,0] = 1/3f;
_matrix[0,1] = 1/3f;
_matrix[0,2] = 1/3f;
_matrix[1,0] = 1/3f;
_matrix[1,1] = 1/3f;
_matrix[1,2] = 1/3f;
_matrix[2,0] = 1/3f;
_matrix[2,1] = 1/3f;
_matrix[2,2] = 1/3f;

ImageAttributes _attributes = 
 new ImageAttributes();
_attributes.SetColorMatrix(_matrix);

Graphics gphGrey = Graphics.FromImage(_image);
gphGrey.DrawImage(_image, 
 bounds, 
 0, 
 0, 
 _image.Width, 
 _image.Height,
 GraphicsUnit.Pixel, 
 _attributes);

gphGrey.Dispose();

O.K. Now, we get to the interesting part.

C#
for(int h=0; h<_image.Height/10; h++)
{
    int _startY = (h*10);

    for(int w=0; w<_image.Width/5; w++)
    {
         int _startX = (w*5);
         int _allBrightness = 0;
         ...

I loop through the image's pixels and because I don't want one ASCII character per pixel, I take one per 10/5. To let every pixel influence the resulting ASCII char, I loop them and calculate the brightness of the amount.

C#
for(int y=0; y<10; y++)
{
    for(int x=0; x<10; x++)
    {
        int _cY = y + _startY;
        int _cX = x + _startX;
        try
        {
            Color _c = _image.GetPixel(_cX, _cY);
            int _b = (int)(_c.GetBrightness() * 10);
            _allBrightness = (_allBrightness + _b);
        }
        catch
        {
            _allBrightness = (_allBrightness + 10);
        }
        ...

Finally, I append different ASCII characters based on the calculated amount:

C#
int _sb = (_allBrightness/10);
if(_sb<25)
{
    _asciiart.Append("#");
}
else if(_sb<30)
{
    ...

That's all

Thanks to The Code Project and Chris Maunder, newtelligence and greetings to all C# coders out there.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer
Germany Germany
Beginning of the nineties started to assemble computers and configure networks. Automation lead to batching and scripting. Arrived on the other side of the trench the HTTP protocol is a constant companion. the journey began with JavaScript, then Perl, PHP and ASP with Visual Basic 5 and JScript, ending with Java and C++. End of the nineties starting to focus .NET, streaked Python, and now JavaScript again. He develops, teaches, trains, coaches and speaks. His topics: HTML5 & Web, Data Access & Performance, Scalable & Testable Designs, Distributed Systems & Services, Security & Trust.

Comments and Discussions

 
GeneralGrayscale, GetPixel method confusion Pin
allapg21-Jun-05 17:08
allapg21-Jun-05 17:08 
GeneralRe: Grayscale, GetPixel method confusion Pin
Daniel Fisher (lennybacon)21-Jun-05 23:23
Daniel Fisher (lennybacon)21-Jun-05 23:23 
GeneralRe: Grayscale, GetPixel method confusion Pin
Daniel Fisher (lennybacon)21-Jun-05 23:24
Daniel Fisher (lennybacon)21-Jun-05 23:24 
GeneralRe: Grayscale, GetPixel method confusion Pin
allapg22-Jun-05 18:02
allapg22-Jun-05 18:02 
GeneralRe: Grayscale, GetPixel method confusion Pin
Daniel Fisher (lennybacon)23-Jun-05 2:39
Daniel Fisher (lennybacon)23-Jun-05 2:39 
GeneralCrop Image Pin
aaccoobb31-Mar-05 0:15
aaccoobb31-Mar-05 0:15 
GeneralRe: Crop Image Pin
Daniel Fisher (lennybacon)21-Jun-05 23:25
Daniel Fisher (lennybacon)21-Jun-05 23:25 
QuestionWhat kind of methods? Pin
Snowjade2-Mar-05 16:03
Snowjade2-Mar-05 16:03 
AnswerRe: What kind of methods? Pin
Daniel Fisher (lennybacon)3-Mar-05 21:34
Daniel Fisher (lennybacon)3-Mar-05 21:34 
GeneralAn improvement... Pin
Miguel Lopes14-Feb-05 0:26
Miguel Lopes14-Feb-05 0:26 
GeneralNow this is just too cool! Pin
GISnet29-Jan-05 19:19
GISnet29-Jan-05 19:19 
GeneralBeautiful program Pin
Phan Dung27-Jan-05 15:25
Phan Dung27-Jan-05 15:25 
GeneralNice and can be perfect Pin
Member 1646325-Jan-05 17:32
Member 1646325-Jan-05 17:32 
GeneralRe: Nice and can be perfect Pin
Daniel Fisher (lennybacon)26-Jan-05 1:15
Daniel Fisher (lennybacon)26-Jan-05 1:15 
Generaladd in install Pin
Pyro Joe22-Jan-05 16:49
Pyro Joe22-Jan-05 16:49 
GeneralRe: add in install Pin
Daniel Fisher (lennybacon)22-Jan-05 23:23
Daniel Fisher (lennybacon)22-Jan-05 23:23 
GeneralA little typo in your code Pin
Eirik18-Jan-05 20:46
Eirik18-Jan-05 20:46 
GeneralRe: A little typo in your code Pin
Daniel Fisher (lennybacon)18-Jan-05 22:15
Daniel Fisher (lennybacon)18-Jan-05 22:15 
Questionhow about html conversion Pin
Member 357484512-Jan-05 22:53
Member 357484512-Jan-05 22:53 
AnswerRe: how about html conversion Pin
Matthew Hanna26-Jun-05 8:09
Matthew Hanna26-Jun-05 8:09 
GeneralRe: how about html conversion Pin
Matthew Hanna26-Jun-05 13:50
Matthew Hanna26-Jun-05 13:50 
Questionhow about html conversion Pin
nokiko12-Jan-05 22:53
nokiko12-Jan-05 22:53 
GeneralVery cool btw: I ported it to VB.net Pin
5-Jan-05 20:45
suss5-Jan-05 20:45 
GeneralRe: Very cool btw: I ported it to VB.net Pin
Daniel Fisher (lennybacon)6-Jan-05 0:30
Daniel Fisher (lennybacon)6-Jan-05 0:30 
GeneralRe: Very cool btw: I ported it to VB.net Pin
Paul Farry6-Jan-05 8:17
professionalPaul Farry6-Jan-05 8:17 

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