diff --git a/app/io/presentation.py b/app/io/presentation.py
new file mode 100644
index 0000000..d27be8c
--- /dev/null
+++ b/app/io/presentation.py
@@ -0,0 +1,58 @@
+# All comments in English.
+
+from pptx import Presentation
+from odf.opendocument import load
+from odf.draw import Page
+from odf.text import P
+
+def normalize_newlines(value):
+    if value is None:
+        return ""
+    return (
+        str(value)
+        .replace("\r\n", "\\n")
+        .replace("\n\r", "\\n")
+        .replace("\r", "\\n")
+        .replace("\n", "\\n")
+    )
+
+def convert_pptx(path):
+    prs = Presentation(path)
+    slides = []
+    for idx, slide in enumerate(prs.slides, start=1):
+        texts = []
+        for shape in slide.shapes:
+            if hasattr(shape, "text"):
+                texts.append(normalize_newlines(shape.text))
+        slides.append((f"Slide_{idx}", "\n".join(texts)))
+    return slides
+
+def convert_ppt(path):
+    # PPT (binary) is not supported by python-pptx.
+    # We convert using LibreOffice headless via subprocess.
+    import subprocess, tempfile, os
+
+    tmp = tempfile.mktemp(suffix=".pptx")
+    subprocess.run(["soffice", "--headless", "--convert-to", "pptx", "--outdir", "/tmp", path])
+    return convert_pptx(tmp)
+
+def convert_odp(path):
+    doc = load(path)
+    slides = []
+    idx = 1
+    for page in doc.getElementsByType(Page):
+        texts = []
+        for p in page.getElementsByType(P):
+            texts.append(normalize_newlines(p.firstChild.data if p.firstChild else ""))
+        slides.append((f"Slide_{idx}", "\n".join(texts)))
+        idx += 1
+    return slides
+
+def convert_presentation(path):
+    if path.endswith(".pptx"):
+        return convert_pptx(path)
+    if path.endswith(".ppt"):
+        return convert_ppt(path)
+    if path.endswith(".odp"):
+        return convert_odp(path)
+    raise ValueError("Unsupported presentation format")