Get a picture - Python-pptx - python

I am trying to read a .pptx file using python-pptx. I managed to get all the content except the image from the presentation. Below is the code i used to identify images other than textframes in the presentation. After identifying i am getting the auto_shape_type as RECTANGLE (1) but nothing about the image.
from pptx import Presentation
from pptx.shapes.picture import Picture
def read_ppt(file):
prs = Presentation(file)
for slide_no, slide in enumerate(prs.slides):
for shape in slide.shapes:
if not shape.has_text_frame:
print(shape.auto_shape_type)
Any help on understanding this problem appreciated. Alternative options are also welcome.

try querying the shape.shape_type. by default, the auto_shape_type returns rectangle as you've observed, though pictures can be inserted into and masked by other shapes as well.
Note the default value for a newly-inserted picture is MSO_AUTO_SHAPE_TYPE.RECTANGLE, which performs no cropping because the extents of the rectangle exactly correspond to the extents of the picture.
the shape_type should return:
Unique integer identifying the type of this shape, unconditionally MSO_SHAPE_TYPE.PICTURE in this case.
You can extract the image content to a file by using its blob property and writing out the binary:
from pptx import Presentation
pres = Presentation('ppt_image.pptx')
slide = pres.slides[0]
shape = slide.shapes[0]
image = shape.image
blob = image.blob
ext = image.ext
with open(f'image.{ext}', 'wb') as file:
file.write(blob)

Related

The position does not match while overlapping the image on the map using folium

This code is draft
bounds_lat = np.array([34.884427, 35.389037])
bounds_lon = np.array([128.761718, 129.305605])
folium.raster_layers.ImageOverlay(image=image_path,
bounds=[[bounds_lat[0], bounds_lon[0]], [bounds_lat[1], bounds_lon[1]]],
mercator_project=True,
opacity=0.3).add_to(map)
My image was incorrectly overlaid in map, so add the mercator_project=True
change the code
bounds_lat = np.array([34.884427, 35.389037])
bounds_lon = np.array([128.761718, 129.305605])
folium.raster_layers.ImageOverlay(image=image_path,
bounds=[[bounds_lat[0], bounds_lon[0]], [bounds_lat[1], bounds_lon[1]]],
mercator_project=True,
opacity=0.3).add_to(map)
error occurred
please help me
Reading the docs yielded the following:
image (string, file or array-like object) – The data you want to draw on the map. * If string, it will be written directly in the output file. * If file, it’s content will be converted as embedded in the output file. * If array-like, it will be converted to PNG base64 string and embedded in the output.
This means you can use both a path to an image or an image array:
But for mercator_project the documentation says:
mercator_project (bool, default False.) – Used only for array-like image. Transforms the data to project (longitude, latitude) coordinates to the Mercator projection. Beware that this will only work if image is an array-like object.
So you must first load the image into an array:
from PIL import Image
image_array= Image.open(image_path)
Or use any other image processing library (OpenCV eg.).
Then you can do:
folium.raster_layers.ImageOverlay(image=image_array,
bounds=[[bounds_lat[0], bounds_lon[0]], [bounds_lat[1], bounds_lon[1]]],
mercator_project=True,
opacity=0.3).add_to(map)

Pixels retrieved from Viewer Node within Blender are darker than the actually rendered image... Why?

I am trying to create a pipeline in which I first render an image using the blender python API (I am using Blender 2.90) and then perform some image processing in python. I want to fetch the image directly from blender without first writing the rendered image to disk and then loading it again. I ran the following code within the blender GUI to do so:
import bpy
import numpy as np
import PIL.Image as Image
from skimage.util import img_as_ubyte
resolution_x = 512
resolution_y = 512
# render settings
scene = bpy.context.scene
scene.render.engine = 'BLENDER_EEVEE'
scene.render.resolution_x = resolution_x
scene.render.resolution_y = resolution_y
scene.render.image_settings.file_format = 'PNG'
scene.render.filepath = "path/to/good_image.png"
# create Viewer Layer in Compositor
scene.use_nodes = True
tree = scene.node_tree
nodes = tree.nodes
links = tree.links
for node in nodes:
nodes.remove(node)
render_layer_node = nodes.new('CompositorNodeRLayers')
viewer_node = nodes.new('CompositorNodeViewer')
links.new(viewer_node.inputs[0], render_layer_node.outputs[0])
# render scene and get pixels from Viewer Node
bpy.ops.render.render(write_still=True)
pixels = bpy.data.images['Viewer Node'].pixels
# do some processing and save
img = np.flip(img_as_ubyte(np.array(pixels[:]).reshape((resolution_y, resolution_x, 4))), axis=0)
Image.fromarray(img).save("path/to/bad_image.png")
Problem: The image I get from the Viewer Node is much darker (bad image) than the image saved in the conventional way (good image). Does anyone have an idea why this happens and how to fix it? Does blender maybe treat pixel values differently than I expect?
Some additional information:
Before conversion to uint8, the values of the alpha channel within the dark image are 1.0 (as they actually should be). Background values in the dark image are not 0.0 or negative (as one might guess from appearance), but 0.05...
What I tried:
I thought that pixels might be scaled within range -1 to 1, so I rescaled the pixels to range 0 to 1 before transforming to uint8... Did not lead to the correct image either :(
It's because the image that you get from the Viewer Node is the one "straight from compositing" before color management takes place. You can have a look at the documentation here: this image is still in the linear space.
Your good_image.png on the other hand is obtained after transformation into the "Display Space" (see diagram in the doc). Hence it was transformed into a log-space, maybe gamma-corrected, etc.
Finally, you can get an image that is close to (but slightly different though) to the good image from the viewer node by calling bpy.data.images['Viewer Node'].save_render(filepath) instead, but there is no way to directly extract the color-managed version without rendering to a file first. You can probably do it yourself by adding PyOpenColorIO to your script and applying the color management from this module.

How to extract ALL IMAGES and text from all pptx file slides using python?

I'm able to read images from pptx file but not all images. I'm unable to extract the images presented in a slide with title or other text. Here is my code and please help me.
from pptx import Presentation
from pptx.enum.shapes import MSO_SHAPE_TYPE
import glob
import os
import codecs
from PIL import Image
import pytesseract
pytesseract.pytesseract.tesseract_cmd = '/usr/local/Cellar/tesseract/4.1.1/bin/tesseract'
from pytesseract import image_to_string
n=0
def write_image(shape):
global n
image = shape.image
# get image
image_bytes = image.blob
# assinging file name, e.g. 'image.jpg'
image_filename = fname[:-5]+'{:03d}.{}'.format(n, image.ext)
n += 1
print(image_filename)
os.chdir("directory_path/readpptx/images")
with open(image_filename, 'wb') as f:
f.write(image_bytes)
os.chdir("directory_path/readpptx")
def visitor(shape):
if shape.shape_type == MSO_SHAPE_TYPE.PICTURE:
write_image(shape)
def iter_picture_shapes(prs1):
for slide in prs1.slides:
for shape in slide.shapes:
visitor(shape)
file = open("directory_path/MyFile.txt","a+")
for each_file in glob.glob("directory_path/*.pptx"):
fname = os.path.basename(each_file)
file.write("-------------------"+fname+"----------------------\n")
prs = Presentation(each_file)
print("---------------"+fname+"-------------------")
for slide in prs.slides:
for shape in slide.shapes:
if hasattr(shape, "text"):
print(shape.text)
file.write(shape.text+"\n")
iter_picture_shapes(prs)
file.close()
Above code is able to extract images from pptx slides which have no text or title but not able to extract images in slides with text or title.
Try also iterating over slide masters and slide layouts. If there are "background" images that's where they will be. The same for shape in slide.shapes: mechanism works on slide masters and slide layouts; they are a variant of the polymorphic Slide object with the same shape-access semantics.
I don't think your problem is strictly related to the presence of a title or text on the slide. Perhaps those particular slides use a layout that includes some background images. If you open the slide and clicking on the image does not select it (give it bounding box) that indicates it is a background image and resides on the slide layout or possibly the slide master. This is how logos are commonly implemented to show up on every slide.
You may also want to consider iterating over the Notes slide for each slide when it has one, if there is text and/or images in there you are interested in. It is uncommon to find images in the slide notes but PowerPoint supports it.
Another approach is the traverse the underlying .pptx package (as a Zip archive) and extract the images that way.

Saving area within a shape (rectangle) as image from multiple powerpoint slides

I'm attempting to grab an image of diagrams constructed within a rectangle on a power point slide deck. I found python-pptx and am able to identify the shapes on each slide. Is there any way to expand this to take a snapshot of the area within the rectangle shape and export it as an image?
# Auto grab the photos created in Powerpoint
from pptx import Presentation
prs = Presentation('ex.pptx')
for slide in prs.slides:
print(slide)
for shape in slide.shapes:
print(shape)
# Identify shape on each slide, find area within, and save as .png
I think you're going to be best off looking at a COM32 type of solution, either writing something in VBA or possibly using the win32com library in Python if you really want a Python solution.
Either way this is going to fire up a "live" PowerPoint application instance and basically run it by remote control. That sort of thing isn't a great idea server-side, but if it's just for personal productivity it might work fine.
python-pptx can't do this sort of thing and probably never will. The rendering engine needs to get involved in this type of work and python-pptx is strictly a .pptx file editor/generator.
With Aspose.Slides for Python, you can easily save presentation shapes to images. The following code example shows you how to save all charts from a presentation to PNG images:
import aspose.slides as slides
import aspose.slides.charts as charts
import aspose.pydrawing as draw
with slides.Presentation("example.pptx") as presentation:
for slide_index, slide in enumerate(presentation.slides):
for shape_index, shape in enumerate(slide.shapes):
# Looking for charts, for example.
if isinstance(shape, charts.Chart):
# Get a chart image.
with shape.get_thumbnail() as chart_image:
# Save the chart image to PNG.
image_path = "chart_image_{}_{}.png".format(slide_index, shape_index)
chart_image.save(image_path, draw.imaging.ImageFormat.png)
Aspose.Slides for Python is a paid product, but you can get a temporary license or use it in a trial mode to evaluate all features for managing presentations. Alternatively, you can use Aspose.Slides Cloud SDK for Python. This package provides a REST-based API for managing presentations as well. The code example below shows you how to do the same using Aspose.Slides Cloud:
import asposeslidescloud
import aspose.pydrawing as draw
from asposeslidescloud.apis.slides_api import SlidesApi
from asposeslidescloud.models import *
slides_api = SlidesApi(None, "my_client_id", "my_client_secret")
file_name = "example.pptx"
# Upload the presentation to the default storage.
with open(file_name, "rb") as file_stream:
slides_api.upload_file(file_name, file_stream)
# Get the number of slides.
slides_info = slides_api.get_slides(file_name)
slide_count = len(slides_info.slide_list)
for slide_index in range(1, slide_count + 1):
# Get the number of shapes on the current slide.
shapes_info = slides_api.get_shapes(file_name, slide_index)
shape_count = len(shapes_info.shapes_links)
for shape_index in range(1, shape_count + 1):
shape = slides_api.get_shape(file_name, slide_index, shape_index)
# Looking for charts, for example.
if shape.type == "Chart":
# Get the chart as a PNG image.
image_path = slides_api.download_shape(file_name, slide_index, shape_index, ShapeExportFormat.PNG)
print("A chart image was saved to " + image_path)
This is also a paid product, but you can make 150 free API calls per month for any purposes.
I work as a Support Developer at Aspose and can answer your questions of these libraries on Aspose.Slides forum.

From Raw binary image data to PNG in Python

After searching for a few hours, I ended up on this link. A little background information follows.
I'm capturing live frames of a running embedded device via a hardware debugger. The captured frames are stored as raw binary files, without headers or format. After looking at the above link and understanding, albeit perfunctorily, the NumPY and Matplotlib, I was able to convert the raw binary data to an image successfully. This is important because I'm not sure if the link to the raw binary file will help any one.
I use this code:
import matplotlib.pyplot as plt # study documentation
import numpy as np # " "
iFile = "FramebufferL0_0.bin" # Layer-A
shape = (430, 430) # length and width of the image
dtype = np.dtype('<u2') # unsigned 16 bit little-endian.
oFile = "FramebufferL0_0.png"
fid = open(iFile, 'rb')
data = np.fromfile(fid, dtype)
image = data.reshape(shape)
plt.imshow(image, cmap = "gray")
plt.savefig(oFile)
plt.show()
Now, the image I'm showing is black and white because the color map is gray-scale (right?). The actual captured frame is NOT black and white. That is, the image I see on my embedded device is "colorful".
My question is, how can I calculate actual color of each pixel from the raw binary file? Is there a way I can get the actual color map of the image from the raw binary? I looked into this example and I'm sure that, if I'm able to calculate the R, G and B channels (and Alpha too), I'll be able to recreate the exact image. An example code would be of much help.
An RGBA image has 4 channels, one for each color and one for the alpha value. The binary file seems to have a single channel, as you don't report an error when performing the data.reshape(shape) operation (the shape for the corresponding RGBA image would be (430, 430, 4)).
I see two potential reasons:
The image actual does have colour information but when you are grabbing the data you are only grabbing one of the four channels.
The image is actually a gray-scale image, but the embedded device shows a pseudocolor image, creating the illusion of colour information. Without knowing what the colourmap is being used, it is hard to help you, other than point you towards matplotlib.pyplot.colormaps(), which lists all already available colour maps in matplotlib.
Could you
a) explain the exact source / type of imaging modality, and
b) show a photo of the output of the embedded device?
PS: Also, at least in my hands, the pasted binary file seems to have a size of 122629, which is incongruent with an image shape of (430,430).

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