Zetter is a Minecraft mod with a simple goal of adding custom drawing interface to create custom paintings in Minecraft
Wiki with instructions and recipes:
Download paintings with Gallery add-on and share your paintings:

Get help, report issues, showcase paintings, servers and learn about new updates:
Zetter & Zetter Gallery showcase:
Mod highlight (pre 0.19 version) by Juri TV
Available translations:
Completed features:
1. Simultaneous canvas edit, dynamic picture updates for all players in range;
2. Dynamic canvas texture loading/unloading;
3. 18 types of frames from all vanilla types of wood, all of them can be decorated with golden nameplate which will show painting name by right-clicking it;
4. Golden frames have more decoration, iron bezel-less frames allow players to create huge seamless paintings by placing them one next to another;
5. Frames could be easily replaced, you can take your painting off the frame and use another;
6. Color code input fields (hex) and HSV sliders for color picking;
7. Color blending options, classic RGB, subtractive, and realistic;
8. Brush tool with smooth edges;
9. Edit up to 2x2 canvases on easel;
10. 16x16 paintings can be combined and placed on wall, resulting in up to 4x4 blocks paintings;
11. Eyedropper, hand and zoom tool for easy navigation;
12. Bucket tool;
13. Save your colors in palettes, recharge palettes with paints and use them on multiple canvases;
14. Hotkeys included;
Core values of this mod:
1. Encourage players to create own pixel artworks and use it in their creations;
2. Do not change vanilla gameplay in any way and try to be as much close to vanilla Minecraft feel as possible;
3. Drawing should be fun and simple;
4. Let power users to be power users as much as it doesn't overcomplicate UI;
5. Server administrators should be able to easily moderate player artworks and decide what is appropriate on their server;
6. Simultaneous canvas edit is super hard to implement properly, but I will because it's fun.
Planned features:
1. Special admin table to check all pictures;
2. Line tool;
3. Setting to use higher resolution of canvases for higher-resolution texture packs, up to 64px on one block.