We have added a new version of chipper (Chipperv3), which needs to allow
unstructured to effective work with all the current Chipper versions.
This implies resizing images with the appropriate resolution and make
sure that Chipper elements are not sorted by unstructured.
In addition, it seems that PDFMiner is being called when calling
Chipper, which adds repeated elements from Chipper and PDFMiner.
To evaluate this PR, you can test the code below with the attached PDF.
The code writes a JSON file with the generated elements. The output can
be examined with `cat out.un.json | python -m json.tool`. There are
three things to check:
1. The size of the image passed to Chipper, which can be identiied in
the layout_height and layout_width attributes, which should have values
3301 and 2550 as shown in the example below:
```
[
{
"element_id": "c0493a7872f227e4172c4192c5f48a06",
"metadata": {
"coordinates": {
"layout_height": 3301,
"layout_width": 2550,
```
2. There should be no repeated elements.
3. Order should be closer to reading order.
The script to run Chipper from unstructured is:
```
from unstructured import __version__
print(__version__.__version__)
import json
from unstructured.partition.auto import partition
from unstructured.staging.base import elements_to_json
elements = json.loads(elements_to_json(partition("Huang_Improving_Table_Structure_Recognition_With_Visual-Alignment_Sequential_Coordinate_Modeling_CVPR_2023_paper-p6.pdf", strategy="hi_res", model_name="chipperv3")))
with open('out.un.json', 'w') as w:
json.dump(elements, w)
```
[Huang_Improving_Table_Structure_Recognition_With_Visual-Alignment_Sequential_Coordinate_Modeling_CVPR_2023_paper-p6.pdf](https://github.com/Unstructured-IO/unstructured/files/13817273/Huang_Improving_Table_Structure_Recognition_With_Visual-Alignment_Sequential_Coordinate_Modeling_CVPR_2023_paper-p6.pdf)
---------
Co-authored-by: Antonio Jimeno Yepes <antonio@unstructured.io>
### Summary
This PR is the second part of `pdfminer` refactor to move it from
`unstructured-inference` repo to `unstructured` repo, the first part is
done in
https://github.com/Unstructured-IO/unstructured-inference/pull/294. This
PR adds logic to merge the extracted layout with the inferred layout.
The updated workflow for the `hi_res` strategy:
* pass the document (as data/filename) to the `inference` repo to get
`inferred_layout` (DocumentLayout)
* pass the `inferred_layout` returned from the `inference` repo and the
document (as data/filename) to the `pdfminer_processing` module, which
first opens the document (create temp file/dir as needed), and splits
the document by pages
* if is_image is `True`, return the passed
inferred_layout(DocumentLayout)
* if is_image is `False`:
* get extracted_layout (TextRegions) from the passed
document(data/filename) by pdfminer
* merge `extracted_layout` (TextRegions) with the passed
`inferred_layout` (DocumentLayout)
* return the `inferred_layout `(DocumentLayout) with updated elements
(all merged LayoutElements) as merged_layout (DocumentLayout)
* pass merged_layout and the document (as data/filename) to the `OCR`
module, which first opens the document (create temp file/dir as needed),
and splits the document by pages (convert PDF pages to image pages for
PDF file)
### Note
This PR also fixes issue #2164 by using functionality similar to the one
implemented in the `fast` strategy workflow when extracting elements by
`pdfminer`.
### TODO
* image extraction refactor to move it from `unstructured-inference`
repo to `unstructured` repo
* improving natural reading order by applying the current default
`xycut` sorting to the elements extracted by `pdfminer`
