image_viewer

SD Card Image Viewer (Config > Info)

The Polyend Tracker Community Edition (CE) reactivates the hardware's built-in FT812 JPEG image viewer across all three devices (Original Tracker, Tracker+, and Tracker Mini) and expands it into a 3-folder user image viewer accessible under Config > Info.

Use it to store hardware synth/MIDI CC charts, music theory and scale references, live setlists, track notes, or custom artwork right on your microSD card.

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1. Accessing the Image Viewer

1. Open Config ([Shift] + [Master] or via the module menu).
2. Select Info in the left column.
3. Choose one of the four entries:
   • About - Displays the firmware version, license info, and credits.
   • Reference - Opens images from /Images/Reference/
   • Notes - Opens images from /Images/Notes/
   • Custom - Opens images from /Images/Custom/

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2. SD Card Folder Structure & File Naming

Create an Images directory at the root of your microSD card with any of the three supported subfolders (Reference, Notes, Custom):

SD Card Root/
└── Images/
    ├── Reference/
    │   ├── 1.jpg
    │   ├── 2.jpg
    │   └── ... (up to 48.jpg)
    ├── Notes/
    │   ├── 1.jpg
    │   └── ... (up to 48.jpg)
    └── Custom/
        ├── 1.jpg
        └── ... (up to 48.jpg)

File Naming Rules

• Name your files 1.jpg through 48.jpg (or 1.jpeg through 48.jpeg).
• Each folder supports up to 48 images, corresponding directly to Pads 1–48 on the desktop Tracker / Tracker+.
• Numbering does not need to be contiguous (for example, if you only place 1.jpg, 5.jpg, and 10.jpg, the Left/Right buttons and Jog-wheel will cycle cleanly through those three images, while pressing Pad 5 jumps directly to 5.jpg).

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3. Image Format Requirements

The Tracker's FT812 graphics coprocessor decodes JPEGs directly in hardware (CMD_LOADIMAGE) and requires Baseline JPEG files:

Property	Requirement
Format	Baseline JPEG (.jpg or .jpeg) - Progressive JPEGs are not supported by the FT812 hardware decoder.
Chroma Subsampling	4:2:0 or 4:4:4 standard YCbCr (or grayscale). Avoid CMYK JPEGs.
Maximum Dimensions	800 × 390 pixels (smaller images are supported and rendered from the top-left of the 800 × 390 viewport).
Maximum File Size	Up to 650 KB per image (800 × 390 JPEGs are typically 40 KB–150 KB).

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4. Converting Images for the Tracker

If an image fails to load, it is almost always either larger than 800 × 390 px or saved as a Progressive JPEG. You can convert any PNG/JPEG to a Tracker-compatible 800 × 390 Baseline JPEG using any of the following tools:

Option A: Using ImageMagick (magick / convert)

# Resize to fit within 800x390 (letterboxed on black) and save as Baseline JPEG:
magick input.png -resize 800x390 -background black -gravity center -extent 800x390 -interlace none -sampling-factor 4:2:0 -quality 90 1.jpg

Option B: Using ffmpeg

# Scale and pad to 800x390 Baseline JPEG:
ffmpeg -i input.png -vf "scale=800:390:force_original_aspect_ratio=decrease,pad=800:390:(ow-iw)/2:(oh-ih)/2:black" -q:v 2 -pix_fmt yuvj420p 1.jpg

Option C: In GIMP / Photoshop

1. Resize or crop the canvas to 800 × 390 px (or smaller).
2. Export as .jpg and uncheck "Progressive" in the JPEG export options.

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5. Hardware Controls

Action	Original Tracker & Tracker+	Tracker Mini
Next Image	Right Arrow, Screen Button 8 (>>), or turn Jog-wheel clockwise	Right D-Pad or Screen Button 8 (>>)
Previous Image	Left Arrow, Screen Button 1 (<<), or turn Jog-wheel counter-clockwise	Left D-Pad or Screen Button 1 (<<)
Jump Directly to Image 1-48	Press Pad 1-48	-
Exit Back to Config	Screen Button 7 (Close) (or Button 8 (Close) when folder is empty)	Screen Button 7 (Close) (or Middle Button / Button 8 when folder is empty)