Update readme

ocr/README.md

@@ -1,32 +1,12 @@
-"""Get image timestamps from Swift camera"""
+# ocr
 
-import os
+Use `pytesseract` (python wrapper for Google's `tesseract` OCR engine) to extract timestamps from images captured with Swift camera, which do not contain exif metadata.
-from glob import glob
-from datetime import datetime
-from tqdm import tqdm
-from PIL import Image
-import pandas as pd
-import pytesseract
 
-input_dir = 'jpg'
+## installation
 
-jpg_names = glob(os.path.join(input_dir, '*.jpg'))
+`tesseract` must be installed, and in your path.  
-dates = []
+ https://github.com/tesseract-ocr/tesseract/wiki
 
-for jpg_name in tqdm(jpg_names):
+```
-    im = Image.open(jpg_name)
+pip install pytesseract
-
+```
-    # Crop image
-    w, h = im.size
-    im = im.crop((w - 550, h - 40, w, h))
-
-    # Perform OCR with tesseract
-    text = pytesseract.image_to_string(im, lang='eng')
-
-    # Convert to datetime object
-    dates.append(datetime.strptime(text, '%d/%m/%Y %H:%M:%S'))
-
-# Save as csv
-df = pd.DataFrame(data=dates, index=jpg_names, columns=['date'])
-df.index.name = 'file'
-df.to_csv('image-dates.csv')