Correct initialization of ImageRecordReader(long height, long width, long channels) for the larger size images in DL4J

I have the jpeg images much wider and higher than values, I'm passing with ImageRecordReader(long height, long width, long channels), say ImageRecordReader(100, 100, 1), while the images themselves are 2000x3000 pixels size and have 3 channels. Will the dl4j process the images vectorization correctly and take not the first 10000 pixel lines (i.e 5 lines o 2000-long lines) but really a square of 100x100 in the top right part of the image?