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simonc

Extracting individual bits from a byte
 

i'm trying to get the data out of a monochrome bmp file which has one bit per
pixel. I can read the byte containing 8 consecutive pixels but I'm getting
tied in knots trying to find the most efficient way of reading the individual
bits into an array.

Grateful for advice

EricG

Extracting individual bits from a byte
 

This might give you some hints:

http://support.microsoft.com/default.aspx/kb/113476

HTH,

Eric

"simonc" wrote:

i'm trying to get the data out of a monochrome bmp file which has one bit per
pixel. I can read the byte containing 8 consecutive pixels but I'm getting
tied in knots trying to find the most efficient way of reading the individual
bits into an array.

Grateful for advice


EricG

Extracting individual bits from a byte
 

And here is another one:

http://support.microsoft.com/kb/185554

"simonc" wrote:

i'm trying to get the data out of a monochrome bmp file which has one bit per
pixel. I can read the byte containing 8 consecutive pixels but I'm getting
tied in knots trying to find the most efficient way of reading the individual
bits into an array.

Grateful for advice


Rick Rothstein

Extracting individual bits from a byte
 

What kind of array are you trying to put it into and how many dimensions
does the array have, one or two (if one, how is the data laid out, column
first or row first)?

--
Rick (MVP - Excel)


"simonc" wrote in message
...
i'm trying to get the data out of a monochrome bmp file which has one bit
per
pixel. I can read the byte containing 8 consecutive pixels but I'm getting
tied in knots trying to find the most efficient way of reading the
individual
bits into an array.

Grateful for advice



simonc

Extracting individual bits from a byte
 

Thanks for this. It turns out And is the key.

To extract the eight bits of a byte I used

for i = 0 to 7
bit(i) = byte And 2^i
next

"EricG" wrote:

This might give you some hints:

http://support.microsoft.com/default.aspx/kb/113476

HTH,

Eric

"simonc" wrote:

i'm trying to get the data out of a monochrome bmp file which has one bit per
pixel. I can read the byte containing 8 consecutive pixels but I'm getting
tied in knots trying to find the most efficient way of reading the individual
bits into an array.

Grateful for advice



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