resize file size question

[armagan]

I convert a pdf page to gif with density 200. file is 196kb @ 1653x2339 resolution. when I use -resize 1700x2200! the file size is now 469kb. the resized image has less pixels then the original so why is it 250% bigger?

[anthony]

For the final image output -density does nothing in terms of the number of pixels, an image has, it defines in stead how big each pixel is in terms of the real world.

However when converting a vector image to a raster image (input) it does determine the number of pixels as vector images are defined in real-world terms, usally in terms of A4 or letter pages. Do for input it does effect things. To get rid of -density effects
change the -density setting of the image after reading it to say the 72 dots per inch default.