What each field means
DPI / PPI
Dots Per Inch embedded in the file metadata. 72 DPI = screen standard. 300 DPI = professional print. This affects physical print size, not pixel count.
Colour Mode
Most photos are RGB (screen). Print workflows need CMYK. Grayscale images have a single channel. Canvas API reads RGB/RGBA; CMYK is inferred from JPEG markers when possible.
Megapixels
Width × height ÷ 1,000,000. Phone cameras export 12–50 MP. Web optimised images are usually under 2 MP. Anything above 8 MP is overkill for web display.
Aspect Ratio
Simplified ratio of width to height. Useful when cropping for social media: Instagram feed = 1:1, Stories = 9:16, YouTube thumbnail = 16:9.