Aspose.Note FOSS for Python — Knowledge Base
How to Read Image Metadata from OneNote in Python

How to Read Image Metadata from OneNote in Python

Every Image node in a OneNote document carries metadata alongside the raw pixel bytes: the original filename, display dimensions (width and height in points), alternative text for accessibility, and optionally a hyperlink URL if the image was linked. Aspose.Note FOSS for Python exposes all these fields through the Image class.

Prerequisites 

pip install aspose-note

Image Properties

PropertyTypeDescription
img.BytesbytesRaw image data. Write to disk with open(name, "wb").write(img.Bytes).
img.FileNamestr | NoneOriginal filename stored in the .one file. None if not stored.
img.Widthfloat | NoneDisplay width in points. None if not stored.
img.Heightfloat | NoneDisplay height in points. None if not stored.
img.AlternativeTextDescriptionstr | NoneAccessibility alt text body. None if not set.
img.AlternativeTextTitlestr | NoneAccessibility alt text title. Always None in v26.2 (parser does not populate it).
img.HyperlinkUrlstr | NoneURL if the image is a clickable hyperlink. None if not linked.
img.Tagslist[NoteTag]OneNote tags attached to this image (star, checkbox, etc.).

Step 1 — Load the Document and Find Images 

from aspose.note import Document, Image

doc = Document("MyNotes.one")
images = doc.GetChildNodes(Image)
print(f"Found {len(images)} image(s)")

Step 2 — Read Metadata for Each Image

Guard all nullable fields with is not None before use:

from aspose.note import Document, Image

doc = Document("MyNotes.one")

for i, img in enumerate(doc.GetChildNodes(Image), start=1):
    print(f"\nImage {i}:")
    print(f"  Filename:    {img.FileName or '(no filename)'}")
    print(f"  Size:        {img.Bytes and len(img.Bytes):,} bytes")

    if img.Width is not None and img.Height is not None:
        print(f"  Dimensions:  {img.Width:.1f} × {img.Height:.1f} pts")

    if img.AlternativeTextDescription:
        print(f"  Alt text:    {img.AlternativeTextDescription}")

    if img.HyperlinkUrl:
        print(f"  Hyperlink:   {img.HyperlinkUrl}")

    if img.Tags:
        for tag in img.Tags:
            print(f"  Tag:         {tag.label or tag.shape}")

Complete Example — Save Images with Metadata Report 

from pathlib import Path
from aspose.note import Document, Image

def report_and_save_images(one_path: str, out_dir: str = "images") -> None:
    doc = Document(one_path)
    images = doc.GetChildNodes(Image)
    if not images:
        print("No images found.")
        return

    out = Path(out_dir)
    out.mkdir(exist_ok=True)

    for i, img in enumerate(images, start=1):
        # Determine save name
        name = img.FileName or f"image_{i}.bin"
        dest = out / name

        # Save bytes
        dest.write_bytes(img.Bytes)

        # Report metadata
        dims = (
            f"{img.Width:.0f}×{img.Height:.0f}pts"
            if img.Width is not None and img.Height is not None
            else "unknown size"
        )
        alt = img.AlternativeTextDescription or ""
        link = img.HyperlinkUrl or ""

        print(f"  [{i}] {name}  {dims}"
              + (f"  alt='{alt}'" if alt else "")
              + (f"  url={link}" if link else ""))

    print(f"\nSaved {len(images)} image(s) to '{out_dir}/'")

report_and_save_images("MyNotes.one")

Filter Images by Property

Images with hyperlinks 

from aspose.note import Document, Image

doc = Document("MyNotes.one")
linked = [img for img in doc.GetChildNodes(Image) if img.HyperlinkUrl]
for img in linked:
    print(f"{img.FileName or 'image'} → {img.HyperlinkUrl}")

Images with alt text 

from aspose.note import Document, Image

doc = Document("MyNotes.one")
with_alt = [img for img in doc.GetChildNodes(Image) if img.AlternativeTextDescription]
for img in with_alt:
    print(f"{img.FileName}: {img.AlternativeTextDescription}")

Notes

  • img.Bytes is always present (returns b"" for unreadable images, never None). Check len(img.Bytes) > 0 before saving.
  • img.AlternativeTextTitle always returns None in version 26.2 — the parser does not populate the title field. Use img.AlternativeTextDescription instead.
  • Dimensions are in points (1 point = 1/72 inch), matching PowerPoint and PDF conventions.

See Also