If i have a jpeg, how can i identify if it is a RGB or CMYK? Is there any tool available which determines it?

I use Photoshop CS2 and using that program you would first open your image and then go to IMAGE> MODE. That will show the different colorspaces and a check will be in front of your colorspace of the picture you opened. Also in CS2 when you open the picture it tells you right at the top of the picture which colorspace that picture is using.

DC

Hi, thanx for the reply.
actually i want to build a logic for determining the color space of an image...so i cannot use photoshop...i need to get the source code of it. Can you help me? Thanks

If you are on a mac, right click>get info and click "more info" should tell you the color space.....

My pc usage has declined in the past few years, but if memory serves me, if you view a folder as a detailed list, there are options to add new sections to the detailed list....one of which "may" include color space.

you want the source code for photoshop?......not gonna happen

Adobe Bridge will also display the color space in the meta data tab.

If i have a jpeg, how can i identify if it is a RGB or CMYK? Is there any tool available which determines it?

Jpegs don't encode in CMYK (or RGB for that matter). The internal color space of a jpeg is called YCbCr, this is the same color space used by PAL television transmission. YCbCr values are typically converted to RGB values by the application when read into the program but they could be converted to CMYK just as well. But, that's not standard practice.

What tells the application program what to use is in the image metadata or an embedded profile. Exif has an sRGB/something else indicator and iptc can have a (usually proprietary) color space field. Adobe has embedded XMP data that specifies the color space mode and profile. If you are trying to write a program to process files from arbitrary sources, good luck. It's like nailing jelly to a tree.

You can use google to track down the various pieces of the puzzle.