Image to file conversion

For further background on this, check out the previous question. Notice that this person seems to be working with grayscale, which can be represented by a byte (values 0-255)

You might want to tell us more about what you are trying to accomplish. Are you trying to convert the pixel color data to numbers, then convert those numbers to human readable text? Or, are you trying to convert the pixel color data to numbers, then store those numbers to a file as byte data (which would not be human readable, but which could be loaded into a program later on)? Seems like you may be confusing the two.

I don't know C#, but maybe you can translate this old VB5 code I did many years ago. I think it will do what you're trying to do. Here's the way it works:

• open the picture file for binary input
• read a string of bytes (I chose to read in 16 at a time, but you can make it anything you want.
• convert each byte in the string to its hex representation and add it to an output string.
• loop through the input string until all bytes have been converted
• write the output string to a file
• loop to read the next string of bytes from the input file.
  

Here's the VB code:

Dim txtIn As String, txtOut As String, txtChr As String
Dim n As Integer

Open "C:\Picture1.tif" For Binary As #1
Open "c:\temp\HEXOut.txt" For Output As #2

'Loop until there is no more to read from the input file

Do While Not LOF(1)

'read 16 bytes from the input (picture) file (#1)
txtIn = Input(16, #1)

'initialize txtOut to an empty string

txtOut = ""

'Loop through txtIn while converting each character (byte)

For n = 1 To Len(txtIn)

'This line uses three functions built into VB5:

' 1. Mid() returns individual characters in a string. In this case it returns a single character (1) at the nth position in the txtIn string

' 2. Asc() returns the ASCII code for a single-character string.

' 3. Hex() converts a decimal value to its hex representation and returns it as a character string

txtChr = Hex(Asc(Mid(txtIn, n, 1)))

'I add a leading zero to hex numbers < 16 (0-F). Otherwise they would be represented as single digits and be harder to read.

If Len(txtChr) < 2 Then txtChr = "0" & txtChr

'add the HEX characters to the output string

txtOut = txtOut & txtChr

Next n

'This line just adds a carriage return and linefeed to the line to make the file easier for humans to read. The output file contains lines of 16 two-character bytes.

txtOut = txtOut & vbCrLf

'Write the line to the output file

Print #2, txtOut

'Loop until the whole file has been read.

Loop

Close

I hope this helps. Sorry I couldn't translate it. One of these days I might try to learn C#, but not today.

-tom-

I'm trying to convert the pixel color data on a 8 bit depth grayscale image(256 types of black to white) to numbers, i want these numbers to be in proper arrangement according to the pixel, as in lines of pixels in the image will be converted to line of numbers.

For eg.

0= black, 255= white , 1-254= intermediate grey between black and white

So, i for a gray scale image

i want the generated code to be like:

0811FF00...... (in hexadecimal),                                                       where 08= 8th grey, 11= 17th grey, FF=white, and 00= black

or

00001000000101111111111100000000..... (in binary code),                      where 00001000= 8th grey, 00010111=17th grey, 11111111= white, and 00000000= black

Previosly, i thought image to byte conversion will give arrays of binary numbers(each represent a pixel depth), i guess i was wrong.

Anyone can guide me in this please?