java - How to get image's (in a file) number of channels (color depth)? -

here have example on how image's dimensions file: https://stackoverflow.com/a/12164026/258483

the method uses imagereader tries not read entire image if not required.

is there similar method obtain image's color depth, 3 colored image , 1 b/w image?

i found imagereader#getrawimagetype(int) method. correct way?

yes,

you can use imagereader.getrawimagetype(imageno). method work of time. unfortunately, in cases return null, notably jpeg images encoded ycbcr (instead of rgb), , common case jpeg...

another way same information, use image meta data object, , @ standard metadata format, information:

iiometadata metadata = imagereader.getimagemetadata(imageno); if (metadata.isstandardformatsupported()) { // true bundled formats     iiometadatanode root = (iiometadatanode) imagemetadata.getastree("javax_imageio_1.0");      // either (as pseudo-xpath):     // /chroma/numchannels[@value], number of channels, 3 rgb     // /data/bitspersample[@value], bits per sample, typically 8,8,8 24 bit rgb } 

you can @ standard format documentation , iiometadatanode api doc more information.