I have problems with the files of opening.bin. The first file isn't good-sized, and the second is good like the image below, and one file of two is like this.
It probably has multiple palettes.
Unlike most bitmap files TIM files do not contain the data to convert the bitmaps data into a color correct image.
They have palettes (multiple as matter of fact) they do not have ANY information as to which palette applies to what part of a multipalette image.
This is handled by the program.
TIM's are loaded directly into the PS1 VRAM the palette location is part of the data (if it's not 16/24 bit image that is).
If you wish to completely decode that data you need to find the palette for the data.
I suggest you check the wiki on TIM data. That will help you.
Cyb