JPG compression

[Broeden]

Hi,

I have a question about the JPG compression in CF2.0

I tested to load a jpg-image of about 2Mb into a bitmap, and the then
save it at once. The saved image is of only 600kB.

bmpMap = new Bitmap("Test.jpg");
bmpMap.Save"Test.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);

Is there a fixed compression rate when saving to JPG, or can it be
adjusted?

/Broeden

 

[Guest]

It's not adjustable.

 

[Broeden]

It's not adjustable.

Is this fixed compression ratio documented someware?

/Broeden

 

[Guest]

there isn't a "fixed ratio". The compression rate depends on the source
data, just like with most compression algorithms. If you want a better
compression rate, try a couple other formats. FOr example, if the images
have large blocks of the same color (like a screen shot) then GIF is far
better than JPG for compression.

 

[Broeden]

there isn't a "fixed ratio". The compression rate depends on the source
data, just like with most compression algorithms. If you want a better
compression rate, try a couple other formats. FOr example, if the images
have large blocks of the same color (like a screen shot) then GIF is far
better than JPG for compression.

I thought there might be a compression ratio adjustment like in many
picture editing software's

see http://www.mdash.net/examples/jpeg_gif.php

/Broeden

 

[Guest]

Nope, the CF has no way to adjust the ratio.