| bytes | Package bytes implements functions for the manipulation of byte slices. |
| errors | Package errors implements functions to manipulate errors. |
| golang.org/x/image/bmp | Package bmp implements a BMP image decoder and encoder. |
| golang.org/x/image/tiff | Package tiff implements a TIFF image decoder and encoder. |
| image | Package image implements a basic 2-D image library. |
| image/color | Package color implements a basic color library. |
| image/draw | Package draw provides image composition functions. |
| image/gif | Package gif implements a GIF image decoder and encoder. |
| image/jpeg | Package jpeg implements a JPEG image decoder and encoder. |
| image/png | Package png implements a PNG image decoder and encoder. |
| io | Package io provides basic interfaces to I/O primitives. |
| math | Package math provides basic constants and mathematical functions. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |