From 7216f9d919754893b42a4a4c6bb991b1692ee86a Mon Sep 17 00:00:00 2001 From: jakaskerl <53253318+jakaskerl@users.noreply.github.com> Date: Tue, 6 Feb 2024 19:34:37 +0100 Subject: [PATCH] Update calibration_reader.rst Fixed focal length formulas --- docs/source/samples/calibration/calibration_reader.rst | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/docs/source/samples/calibration/calibration_reader.rst b/docs/source/samples/calibration/calibration_reader.rst index 247d77254..f9d928730 100644 --- a/docs/source/samples/calibration/calibration_reader.rst +++ b/docs/source/samples/calibration/calibration_reader.rst @@ -27,7 +27,7 @@ Here's theoretical calculation of the focal length in pixels: .. math:: - f_x = \text{width}_x \cdot \frac{1}{\tan \left(\frac{\text{HFOV}_x}{2}\frac{\pi}{180}\right)} + f_x = \text{width}_x \cdot \frac{1}{2 \cdot \tan \left(\frac{\text{HFOV}_x}{2}\frac{\pi}{180}\right)} To get the HFOV you can use `this script `__, which also works for wide-FOV cameras and allows you to specif alpha parameter. @@ -36,13 +36,13 @@ With 400P (640x400) camera resolution where HFOV=71.9 degrees: .. math:: - f_x = 640 \cdot \frac{1}{\tan \left(\frac{71.9}{2}\frac{\pi}{180}\right)} = 441.25 + f_x = 640 \cdot \frac{1}{2 \cdot \tan \left(\frac{71.9}{2}\frac{\pi}{180}\right)} = 441.25 And for 800P (1280x800) camera resolution where HFOV=71.9 degrees: .. math:: - f_x = 1280 \cdot \frac{1}{\tan \left(\frac{71.9}{2}\frac{\pi}{180}\right)} = 882.5 + f_x = 1280 \cdot \frac{1}{2 \cdot \tan \left(\frac{71.9}{2}\frac{\pi}{180}\right)} = 882.5