Displaying JPEG images

In this guide, you will load a Base64 encoded JPEG image, decode it, and display it on a DirectGPU screen.

Requirements

Before starting, make sure you have:

• CC:Tweaked installed
• DirectGPU installed
• A DirectGPU peripheral attached
• A Base64 encoded JPEG image

Finding the GPU

First, get the DirectGPU peripheral:

local gpu = peripheral.find("directgpu")

Create a display:

local displayId = gpu.autoDetectAndCreateDisplay()

Decoding a JPEG

DirectGPU can decode JPEG images directly.

Use decodeJPEG:

local image = gpu.decodeJPEG(base64JpegData)

This returns an image table containing pixel data.

If you want to resize the image while decoding, use decodeAndScaleJPEG:

local image = gpu.decodeAndScaleJPEG(
    base64JpegData,
    128,
    128
)

Displaying a JPEG fullscreen

If you simply want to fill the display with an image, use loadJPEGFullscreen:

gpu.loadJPEGFullscreen(
    displayId,
    base64JpegData
)

Then update the display:

gpu.updateDisplay(displayId)

Displaying part of an image

You can also update only a region of the display:

gpu.loadJPEGRegionBytes(
    displayId,
    base64JpegData,
    20,
    20,
    128,
    128
)

gpu.updateDisplay(displayId)