From 85dd1893342288b0f813e4b88f66254040048b13 Mon Sep 17 00:00:00 2001
From: "Jorj X. McKie" <jorj.x.mckie@outlook.de>
Date: Mon, 3 Sep 2018 10:05:33 -0400
Subject: [PATCH] Viewer for arbitrary images
---
Demo_Img_Viewer.py | 114 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 114 insertions(+)
create mode 100644 Demo_Img_Viewer.py
diff --git a/Demo_Img_Viewer.py b/Demo_Img_Viewer.py
new file mode 100644
index 00000000..67da8392
--- /dev/null
+++ b/Demo_Img_Viewer.py
@@ -0,0 +1,114 @@
+import PySimpleGUI as sg
+import os
+from PIL import Image, ImageTk
+import io
+"""
+Simple Image Browser based on PySimpleGUI
+--------------------------------------------
+There are some improvements compared to the PNG browser of the repository:
+1. Paging is cyclic, i.e. automatically wraps around if file index is outside
+2. Supports all file types that are valid PIL images
+3. Limits the maximum form size to the physical screen
+4. When selecting an image from the listbox, subsequent paging uses its index
+5. Paging performance improved significantly because of using PIL
+
+Dependecies
+------------
+Python v3
+PIL
+"""
+# Get the folder containing the images from the user
+rc, folder = sg.GetPathBox('Image Browser', 'Image folder to open', default_path='')
+if not rc or not folder:
+ sg.MsgBoxCancel('Cancelling')
+ raise SystemExit()
+
+# PIL supported image types
+img_types = (".png", ".jpg", "jpeg", ".tiff", ".bmp")
+
+# get list of files in folder
+flist0 = os.listdir(folder)
+
+# create sub list of image files (no sub folders, no wrong file types)
+fnames = [f for f in flist0 if os.path.isfile(os.path.join(folder,f)) and f.lower().endswith(img_types)]
+
+num_files = len(fnames) # number of iamges found
+if num_files == 0:
+ sg.MsgBox('No files in folder')
+ raise SystemExit()
+
+del flist0 # no longer needed
+
+#------------------------------------------------------------------------------
+# use PIL to read data of one image
+#------------------------------------------------------------------------------
+def get_img_data(f, maxsize = (1200, 850), first = False):
+ """Generate image data using PIL
+ """
+ img = Image.open(f)
+ img.thumbnail(maxsize)
+ if first: # tkinter is inactive the first time
+ bio = io.BytesIO()
+ img.save(bio, format = "PNG")
+ del img
+ return bio.getvalue()
+ return ImageTk.PhotoImage(img)
+#------------------------------------------------------------------------------
+
+
+# create the form that also returns keyboard events
+form = sg.FlexForm('Image Browser', return_keyboard_events=True,
+ location=(0, 0), use_default_focus=False)
+
+# make these 2 elements outside the layout as we want to "update" them later
+# initialize to the first file in the list
+filename = os.path.join(folder, fnames[0]) # name of first file in list
+image_elem = sg.Image(data = get_img_data(filename, first = True))
+filename_display_elem = sg.Text(filename, size=(80, 3))
+file_num_display_elem = sg.Text('File 1 of {}'.format(num_files), size=(15,1))
+
+# define layout, show and read the form
+col = [[filename_display_elem],
+ [image_elem],
+ [sg.ReadFormButton('Next', size=(8,2)), sg.ReadFormButton('Prev',
+ size=(8,2)), file_num_display_elem]]
+
+col_files = [[sg.Listbox(values = fnames, size=(60,30), key='listbox')],
+ [sg.ReadFormButton('Read')]]
+
+layout = [[sg.Column(col_files), sg.Column(col)]]
+
+button, values = form.LayoutAndRead(layout) # Shows form on screen
+
+# loop reading the user input and displaying image, filename
+i=0
+while True:
+
+ # perform button and keyboard operations
+ if button is None:
+ break
+ elif button in ('Next', 'MouseWheel:Down', 'Down:40', 'Next:34'):
+ i += 1
+ if i >= num_files:
+ i -= num_files
+ elif button in ('Prev', 'MouseWheel:Up', 'Up:38', 'Prior:33'):
+ i -= 1
+ if i < 0:
+ i = num_files + i
+
+ if button == 'Read': # something from the listbox
+ f = values["listbox"][0] # selected filename
+ filename = os.path.join(folder, f) # read this file
+ i = fnames.index(f) # update running index
+ else:
+ filename = os.path.join(folder, fnames[i])
+
+ # update window with new image
+ image_elem.Update(data=get_img_data(filename))
+ # update window with filename
+ filename_display_elem.Update(filename)
+ # update page display
+ file_num_display_elem.Update('File {} of {}'.format(i+1, num_files))
+
+ # read the form
+ button, values = form.Read()