Hacktoberfest 2026: los issues que los mantenedores marcaron para octubre, abiertos y aptos para principiantes. Explorar issues de Hacktoberfest

cropping images leads to poorer results

Abierto
#2,007 0 comentarios 0 reacciones 0 asignados Ver en GitHub

Los mantenedores suelen responder en 1 día

Nadie ha tomado este issue todavía.

Evaluación

Dificultad
4/5
Tiempo estimado
3-5 días
Aptitud para principiantes
22/100
Tipo de issue
Error
Claridad
Necesita aclaración
Estado de actividad
Estancado
Stack tecnológico
python, pytorch

Línea de trabajo

Start by running the reproduction script on the attached images.zip, comparing the detection output for the original and cropped versions of each image; the predictor is built by ocr_predictor with db_resnet34, crnn_vgg16_bn, assume_straight_pages=False and straighten_pages=True. Find where the two runs diverge (detection boxes or page straightening, not recognition alone). Done means either a documented explanation of the difference or a reproducible case with a proposed change. The thread has no comments, so expect to work without maintainer guidance.

Escrito por el modelo de indexación a partir del texto del issue.

Descripción

type: bug
Bug description

In order to save memory I am cropping images from shape (1080, 1920, 3) to shape (1080, 1080, 3).

In the original image docTR is able to find all the numbers that I am looking for.
In the same but cropped image docTR does not find all numbers.

I would expect the results to be the same.
Is there a reason for the results I am getting?

Code snippet to reproduce the bug
from pathlib import Path
import cv2
from doctr.io import DocumentFile
from doctr.models import ocr_predictor


# initialize OCR predictor
predictor = ocr_predictor(
    det_arch="db_resnet34",
    reco_arch="crnn_vgg16_bn",
    pretrained=True,
    assume_straight_pages=False,
    straighten_pages=True,
)

for i in range(1, 5):
    print(f"\nProcessing image #{i}:")

    for crop in [False, True]:
        if crop:
            preprocessed_image_filename = f"image_{i}__cropped.png"
        else:
            preprocessed_image_filename = f"image_{i}__original.png"
        preprocessed_image_path = Path(__file__).parent / "images" / preprocessed_image_filename

        # Load the preprocessed image
        preprocessed = cv2.imread(str(preprocessed_image_path))

        # Load OCR predictor with requested models
        _, buf = cv2.imencode(".png", preprocessed)
        doc = DocumentFile.from_images(buf.tobytes())

        # Run OCR
        result = predictor(doc)

        # Print plain text result
        output_text = ""
        for page in result.pages:
            for block in page.blocks:
                for line in block.lines:
                    output_text += " ".join(w.value + " " for w in line.words)
        print(f"OCR Result for {preprocessed_image_filename} (Crop: {crop}):\n{output_text}\n")

images.zip

Error traceback

running the script gives the following output:

Processing image #1:
OCR Result for image_1__original.png (Crop: False):
490374 303  2 - 

OCR Result for image_1__cropped.png (Crop: True):
- -  - -  -  - - 49037 -  - -  -  - ( - 0. 2 I à  - - à  - . r . - - - a à -  - - 


Processing image #2:
OCR Result for image_2__original.png (Crop: False):
489556 5022 - - à 1   

OCR Result for image_2__cropped.png (Crop: True):
. 2 I a - - . -  -  - 5022  - - - - - -  - - I 89556 


Processing image #3:
OCR Result for image_3__original.png (Crop: False):
489556 303  S  2 A 

OCR Result for image_3__cropped.png (Crop: True):
. I - ( 2  G - - - - - I -  -  -  -  - 56 1 


Processing image #4:
OCR Result for image_4__original.png (Crop: False):
-  5 489556 3012 à 

OCR Result for image_4__cropped.png (Crop: True):
A 489556 a  à  -  -  -  -  - I - I - - - - à I I 

Environment

Collecting environment information...

DocTR version: v1.0.0
PyTorch version: 2.7.1+cu126 (torchvision 0.22.1+cu126)
OpenCV version: 4.11.0
OS: Ubuntu 24.04.2 LTS
Python version: 3.12.3
Is CUDA available (PyTorch): No
CUDA runtime version: Could not collect
GPU models and configuration: Could not collect
Nvidia driver version: Could not collect
cuDNN version: Could not collect

Lenguaje dominante
Python
Estrellas
6.4k
Forks
684
Merge medio
20 h 28 min
PR fusionados (30 d)
28

Preparar el entorno

Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
  2. Comenta en el issue que vas a ocuparte — evita que dos personas hagan lo mismo.
  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

Más de mindee/doctr

Todos los issues de mindee/doctr

Issues similares

Más issues de Python

Recibe los nuevos issues en tu correo

Un resumen breve de issues de GitHub para principiantes.