iz_helpers added

iz_helpers/image.py

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+import requests
+from PIL import Image
+import numpy as np
+
+
+def shrink_and_paste_on_blank(current_image, mask_width):
+    """
+    Decreases size of current_image by mask_width pixels from each side,
+    then adds a mask_width width transparent frame, 
+    so that the image the function returns is the same size as the input. 
+    :param current_image: input image to transform
+    :param mask_width: width in pixels to shrink from each side
+    """
+
+    height = current_image.height
+    width = current_image.width
+
+    # shrink down by mask_width
+    prev_image = current_image.resize(
+        (height-2*mask_width, width-2*mask_width))
+    prev_image = prev_image.convert("RGBA")
+    prev_image = np.array(prev_image)
+
+    # create blank non-transparent image
+    blank_image = np.array(current_image.convert("RGBA"))*0
+    blank_image[:, :, 3] = 1
+
+    # paste shrinked onto blank
+    blank_image[mask_width:height-mask_width,
+                mask_width:width-mask_width, :] = prev_image
+    prev_image = Image.fromarray(blank_image)
+
+    return prev_image

iz_helpers/video.py

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+import numpy as np
+import imageio
+from PIL import Image
+
+def write_video(file_path, frames, fps, reversed=True, start_frame_dupe_amount=15, last_frame_dupe_amount=30):
+    """
+    Writes frames to an mp4 video file
+    :param file_path: Path to output video, must end with .mp4
+    :param frames: List of PIL.Image objects
+    :param fps: Desired frame rate
+    :param reversed: if order of images to be reversed (default = True)
+    """
+    if reversed == True:
+        frames = frames[::-1]
+
+    # Get dimensions of the frames
+    w, h = frames[0].size
+
+    # Create an imageio video writer
+    writer = imageio.get_writer(file_path, fps=fps)
+
+    # Duplicate the start and end frames
+    start_frames = [frames[0]] * start_frame_dupe_amount
+    end_frames = [frames[-1]] * last_frame_dupe_amount
+
+    # Write the duplicated frames to the video writer
+    for frame in start_frames:
+        # Convert PIL image to numpy array
+        np_frame = np.array(frame)
+        writer.append_data(np_frame)
+
+    # Write the frames to the video writer
+    for frame in frames:
+        np_frame = np.array(frame)
+        writer.append_data(np_frame)
+
+    # Write the duplicated frames to the video writer
+    for frame in  end_frames:
+        np_frame = np.array(frame)
+        writer.append_data(np_frame)
+
+    # Close the video writer
+    writer.close()