an image filled with the background color (can be used as a background before the first frame) - if the global color table is not available this is transparent black
the color depth/resolution in bits per color (in the original) [1-8 bits]
comments in the file and on with frame they where found
each frame of the GIF (decoded into single images)
the global color table for the GIF
the height of the image in pixels (logical screen size)
if non-zero the pixel aspect ratio will be from 4:1 to 1:4 in 1/64th increments
if the colors in the global color table are ordered after decreasing importance
the total duration of the gif in milliseconds (all delays added together) - will be Infinity if there is a frame with 0 delay
the width of the image in pixels (logical screen size)
all application extensions found