Support Indexing Images via OCR (#823)

- Added support for uploading .jpeg, .jpg, and .png files to Khoj from Web, Desktop app
- Updating indexer to generate raw text and entries using RapidOCR
- Details
  * added support for indexing images via ocr
  * fixed pyproject.toml
  * Update src/khoj/processor/content/images/image_to_entries.py
     Co-authored-by: Debanjum <debanjum@gmail.com>
  * Update src/khoj/processor/content/images/image_to_entries.py
     Co-authored-by: Debanjum <debanjum@gmail.com>
  * removed redudant try except blocks
  * updated desktop js file to support image formats
  * added tests for jpg and png
  * Fix processing for image to entries files
  * Update unit tests with working image indexer
  * Change png test from version verificaition to open-cv verification

---------

Co-authored-by: Debanjum <debanjum@gmail.com>
Co-authored-by: sabaimran <narmiabas@gmail.com>

src/interface/desktop/main.js

@@ -19,7 +19,7 @@ const textFileTypes = [
     'org', 'md', 'markdown', 'txt', 'html', 'xml',
     // Other valid text file extensions from https://google.github.io/magika/model/config.json
     'appleplist', 'asm', 'asp', 'batch', 'c', 'cs', 'css', 'csv', 'eml', 'go', 'html', 'ini', 'internetshortcut', 'java', 'javascript', 'json', 'latex', 'lisp', 'makefile', 'markdown', 'mht', 'mum', 'pem', 'perl', 'php', 'powershell', 'python', 'rdf', 'rst', 'rtf', 'ruby', 'rust', 'scala', 'shell', 'smali', 'sql', 'svg', 'symlinktext', 'txt', 'vba', 'winregistry', 'xml', 'yaml']
-const binaryFileTypes = ['pdf']
+const binaryFileTypes = ['pdf', 'jpg', 'jpeg', 'png']
 const validFileTypes = textFileTypes.concat(binaryFileTypes);
 
 const schema = {

src/khoj/interface/web/chat.html

@@ -48,8 +48,8 @@ Get the Khoj [Desktop](https://khoj.dev/downloads), [Obsidian](https://docs.khoj
 
 To get started, just start typing below. You can also type / to see a list of commands.
 `.trim()
-        const allowedExtensions = ['text/org', 'text/markdown', 'text/plain', 'text/html', 'application/pdf', 'application/vnd.openxmlformats-officedocument.wordprocessingml.document'];
-        const allowedFileEndings = ['org', 'md', 'txt', 'html', 'pdf', 'docx'];
+        const allowedExtensions = ['text/org', 'text/markdown', 'text/plain', 'text/html', 'application/pdf', 'image/jpeg', 'image/png', 'application/vnd.openxmlformats-officedocument.wordprocessingml.document'];
+        const allowedFileEndings = ['org', 'md', 'txt', 'html', 'pdf', 'jpg', 'jpeg', 'png', 'docx'];
         let chatOptions = [];
         function createCopyParentText(message) {
             return function(event) {
@@ -974,7 +974,12 @@ To get started, just start typing below. You can also type / to see a list of co
                                 fileType = "text/html";
                             } else if (fileExtension === "pdf") {
                                 fileType = "application/pdf";
-                            } else {
+                            } else if (fileExtension === "jpg" || fileExtension === "jpeg"){
+                                fileType = "image/jpeg";
+                            } else if (fileExtension === "png") {
+                                fileType = "image/png";
+                            }
+                            else {
                                 // Skip this file if its type is not supported
                                 resolve();
                                 return;

src/khoj/processor/content/images/image_to_entries.py

@@ -0,0 +1,118 @@
+import base64
+import logging
+import os
+from datetime import datetime
+from typing import Dict, List, Tuple
+
+from rapidocr_onnxruntime import RapidOCR
+
+from khoj.database.models import Entry as DbEntry
+from khoj.database.models import KhojUser
+from khoj.processor.content.text_to_entries import TextToEntries
+from khoj.utils.helpers import timer
+from khoj.utils.rawconfig import Entry
+
+logger = logging.getLogger(__name__)
+
+
+class ImageToEntries(TextToEntries):
+    def __init__(self):
+        super().__init__()
+
+    # Define Functions
+    def process(
+        self, files: dict[str, str] = None, full_corpus: bool = True, user: KhojUser = None, regenerate: bool = False
+    ) -> Tuple[int, int]:
+        # Extract required fields from config
+        if not full_corpus:
+            deletion_file_names = set([file for file in files if files[file] == b""])
+            files_to_process = set(files) - deletion_file_names
+            files = {file: files[file] for file in files_to_process}
+        else:
+            deletion_file_names = None
+
+        # Extract Entries from specified image files
+        with timer("Extract entries from specified Image files", logger):
+            file_to_text_map, current_entries = ImageToEntries.extract_image_entries(files)
+
+        # Split entries by max tokens supported by model
+        with timer("Split entries by max token size supported by model", logger):
+            current_entries = self.split_entries_by_max_tokens(current_entries, max_tokens=256)
+
+        # Identify, mark and merge any new entries with previous entries
+        with timer("Identify new or updated entries", logger):
+            num_new_embeddings, num_deleted_embeddings = self.update_embeddings(
+                current_entries,
+                DbEntry.EntryType.IMAGE,
+                DbEntry.EntrySource.COMPUTER,
+                "compiled",
+                logger,
+                deletion_file_names,
+                user,
+                regenerate=regenerate,
+                file_to_text_map=file_to_text_map,
+            )
+
+        return num_new_embeddings, num_deleted_embeddings
+
+    @staticmethod
+    def extract_image_entries(image_files) -> Tuple[Dict, List[Entry]]:  # important function
+        """Extract entries by page from specified image files"""
+        file_to_text_map = dict()
+        entries: List[str] = []
+        entry_to_location_map: List[Tuple[str, str]] = []
+        for image_file in image_files:
+            try:
+                loader = RapidOCR()
+                bytes = image_files[image_file]
+                # write the image to a temporary file
+                timestamp_now = datetime.utcnow().timestamp()
+                # use either png or jpg
+                if image_file.endswith(".png"):
+                    tmp_file = f"tmp_image_file_{timestamp_now}.png"
+                elif image_file.endswith(".jpg") or image_file.endswith(".jpeg"):
+                    tmp_file = f"tmp_image_file_{timestamp_now}.jpg"
+                with open(tmp_file, "wb") as f:
+                    bytes = image_files[image_file]
+                    f.write(bytes)
+                try:
+                    image_entries_per_file = ""
+                    result, _ = loader(tmp_file)
+                    if result:
+                        expanded_entries = [text[1] for text in result]
+                        image_entries_per_file = " ".join(expanded_entries)
+                except ImportError:
+                    logger.warning(f"Unable to process file: {image_file}. This file will not be indexed.")
+                    continue
+                entry_to_location_map.append((image_entries_per_file, image_file))
+                entries.extend([image_entries_per_file])
+                file_to_text_map[image_file] = image_entries_per_file
+            except Exception as e:
+                logger.warning(f"Unable to process file: {image_file}. This file will not be indexed.")
+                logger.warning(e, exc_info=True)
+            finally:
+                if os.path.exists(tmp_file):
+                    os.remove(tmp_file)
+        return file_to_text_map, ImageToEntries.convert_image_entries_to_maps(entries, dict(entry_to_location_map))
+
+    @staticmethod
+    def convert_image_entries_to_maps(parsed_entries: List[str], entry_to_file_map) -> List[Entry]:
+        "Convert each image entries into a dictionary"
+        entries = []
+        for parsed_entry in parsed_entries:
+            entry_filename = entry_to_file_map[parsed_entry]
+            # Append base filename to compiled entry for context to model
+            heading = f"{entry_filename}\n"
+            compiled_entry = f"{heading}{parsed_entry}"
+            entries.append(
+                Entry(
+                    compiled=compiled_entry,
+                    raw=parsed_entry,
+                    heading=heading,
+                    file=f"{entry_filename}",
+                )
+            )
+
+        logger.debug(f"Converted {len(parsed_entries)} image entries to dictionaries")
+
+        return entries

src/khoj/routers/indexer.py

@@ -9,6 +9,7 @@ from starlette.authentication import requires
 from khoj.database.models import GithubConfig, KhojUser, NotionConfig
 from khoj.processor.content.docx.docx_to_entries import DocxToEntries
 from khoj.processor.content.github.github_to_entries import GithubToEntries
+from khoj.processor.content.images.image_to_entries import ImageToEntries
 from khoj.processor.content.markdown.markdown_to_entries import MarkdownToEntries
 from khoj.processor.content.notion.notion_to_entries import NotionToEntries
 from khoj.processor.content.org_mode.org_to_entries import OrgToEntries
@@ -41,6 +42,7 @@ class IndexerInput(BaseModel):
     markdown: Optional[dict[str, str]] = None
     pdf: Optional[dict[str, bytes]] = None
     plaintext: Optional[dict[str, str]] = None
+    image: Optional[dict[str, bytes]] = None
     docx: Optional[dict[str, bytes]] = None
 
 
@@ -65,7 +67,14 @@ async def update(
     ),
 ):
     user = request.user.object
-    index_files: Dict[str, Dict[str, str]] = {"org": {}, "markdown": {}, "pdf": {}, "plaintext": {}, "docx": {}}
+    index_files: Dict[str, Dict[str, str]] = {
+        "org": {},
+        "markdown": {},
+        "pdf": {},
+        "plaintext": {},
+        "image": {},
+        "docx": {},
+    }
     try:
         logger.info(f"📬 Updating content index via API call by {client} client")
         for file in files:
@@ -81,6 +90,7 @@ async def update(
             markdown=index_files["markdown"],
             pdf=index_files["pdf"],
             plaintext=index_files["plaintext"],
+            image=index_files["image"],
             docx=index_files["docx"],
         )
 
@@ -133,6 +143,7 @@ async def update(
         "num_markdown": len(index_files["markdown"]),
         "num_pdf": len(index_files["pdf"]),
         "num_plaintext": len(index_files["plaintext"]),
+        "num_image": len(index_files["image"]),
         "num_docx": len(index_files["docx"]),
     }
 
@@ -300,6 +311,23 @@ def configure_content(
         logger.error(f"🚨 Failed to setup Notion: {e}", exc_info=True)
         success = False
 
+    try:
+        # Initialize Image Search
+        if (search_type == state.SearchType.All.value or search_type == state.SearchType.Image.value) and files[
+            "image"
+        ]:
+            logger.info("🖼️ Setting up search for images")
+            # Extract Entries, Generate Image Embeddings
+            text_search.setup(
+                ImageToEntries,
+                files.get("image"),
+                regenerate=regenerate,
+                full_corpus=full_corpus,
+                user=user,
+            )
+    except Exception as e:
+        logger.error(f"🚨 Failed to setup images: {e}", exc_info=True)
+        success = False
     try:
         if (search_type == state.SearchType.All.value or search_type == state.SearchType.Docx.value) and files["docx"]:
             logger.info("📄 Setting up search for docx")

src/khoj/utils/helpers.py

@@ -118,9 +118,9 @@ def get_file_type(file_type: str, file_content: bytes) -> tuple[str, str]:
     elif file_type in ["application/msword", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"]:
         return "docx", encoding
     elif file_type in ["image/jpeg"]:
-        return "jpeg", encoding
+        return "image", encoding
     elif file_type in ["image/png"]:
-        return "png", encoding
+        return "image", encoding
     elif content_group in ["code", "text"]:
         return "plaintext", encoding
     else:

src/khoj/utils/rawconfig.py

@@ -65,6 +65,7 @@ class ContentConfig(ConfigBase):
     plaintext: Optional[TextContentConfig] = None
     github: Optional[GithubContentConfig] = None
     notion: Optional[NotionContentConfig] = None
+    image: Optional[TextContentConfig] = None
     docx: Optional[TextContentConfig] = None
 
 

tests/test_image_to_entries.py

@@ -0,0 +1,21 @@
+import os
+
+from khoj.processor.content.images.image_to_entries import ImageToEntries
+
+
+def test_png_to_jsonl():
+    with open("tests/data/images/testocr.png", "rb") as f:
+        image_bytes = f.read()
+    data = {"tests/data/images/testocr.png": image_bytes}
+    entries = ImageToEntries.extract_image_entries(image_files=data)
+    assert len(entries) == 2
+    assert "opencv-python" in entries[1][0].raw
+
+
+def test_jpg_to_jsonl():
+    with open("tests/data/images/nasdaq.jpg", "rb") as f:
+        image_bytes = f.read()
+    data = {"tests/data/images/nasdaq.jpg": image_bytes}
+    entries = ImageToEntries.extract_image_entries(image_files=data)
+    assert len(entries) == 2
+    assert "investments" in entries[1][0].raw