cv2_puttext_wrapper.py

import cv2
import numpy as np


def draw_text(
    img,
    *,
    text,
    uv_top_left,
    color=(255, 255, 255),
    fontScale=0.5,
    thickness=1,
    fontFace=cv2.FONT_HERSHEY_SIMPLEX,
    outline_color=(0, 0, 0),
    line_spacing=1.5,
):
    """
    Draws multiline with an outline.
    """
    assert isinstance(text, str)

    uv_top_left = np.array(uv_top_left, dtype=float)
    assert uv_top_left.shape == (2,)

    for line in text.splitlines():
        (w, h), _ = cv2.getTextSize(
            text=line,
            fontFace=fontFace,
            fontScale=fontScale,
            thickness=thickness,
        )
        uv_bottom_left_i = uv_top_left + [0, h]
        org = tuple(uv_bottom_left_i.astype(int))

        if outline_color is not None:
            cv2.putText(
                img,
                text=line,
                org=org,
                fontFace=fontFace,
                fontScale=fontScale,
                color=outline_color,
                thickness=thickness * 3,
                lineType=cv2.LINE_AA,
            )
        cv2.putText(
            img,
            text=line,
            org=org,
            fontFace=fontFace,
            fontScale=fontScale,
            color=color,
            thickness=thickness,
            lineType=cv2.LINE_AA,
        )

        uv_top_left += [0, h * line_spacing]

Sample image:

Just curious, what does uv mean?

Ah, just the (u, v) image coordinates. In this case, from the top-left on the text bounding box, whereas org for cv2.putText is from the bottom-left of the text bounding box.

Very helpful. Thanks!

Thank you so much!