docs/examples/convert_images_to_2d.ipynb

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 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Convert camera images to pixels on a s square grid"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from ctapipe.utils import get_dataset_path\n",
    "from ctapipe.visualization import CameraDisplay\n",
    "from ctapipe.instrument import SubarrayDescription\n",
    "from ctapipe.io import EventSource\n",
    "from ctapipe.image.toymodel import Gaussian\n",
    "import matplotlib.pyplot as plt\n",
    "import astropy.units as u"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# get the subarray from an example file\n",
    "subarray = SubarrayDescription.read(\"dataset://gamma_prod5.simtel.zst\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Geometries with square pixels\n",
    "\n",
    "Define a camera geometry and generate a dummy image:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "geom = subarray.tel[40].camera.geometry\n",
    "model = Gaussian(\n",
    "    x=0.05 * u.m,\n",
    "    y=0.05 * u.m,\n",
    "    width=0.01 * u.m,\n",
    "    length=0.05 * u.m,\n",
    "    psi=\"30d\",\n",
    ")\n",
    "_, image, _ = model.generate_image(geom, intensity=500, nsb_level_pe=3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "CameraDisplay(geom, image)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The `CameraGeometry` has functions to convert the 1d image arrays to 2d arrays and back to the 1d array:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "image_square = geom.image_to_cartesian_representation(image)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "plt.imshow(image_square)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "image_1d = geom.image_from_cartesian_representation(image_square)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "CameraDisplay(geom, image_1d)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Geometries with hexagonal pixels\n",
    "\n",
    "Define a camera geometry and generate a dummy image:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "geom = subarray.tel[1].camera.geometry\n",
    "model = Gaussian(\n",
    "    x=0.5 * u.m,\n",
    "    y=0.5 * u.m,\n",
    "    width=0.1 * u.m,\n",
    "    length=0.2 * u.m,\n",
    "    psi=\"30d\",\n",
    ")\n",
    "_, image, _ = model.generate_image(geom, intensity=5000)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "CameraDisplay(geom, image)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "image_square = geom.image_to_cartesian_representation(image)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Conversion into square geometry\n",
    "\n",
    "Since the resulting array has square pixels, the pixel grid has to be rotated and distorted.\n",
    "This is reversible (The `image_from_cartesian_representation` method takes care of this):"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "plt.imshow(image_square)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "image_1d = geom.image_from_cartesian_representation(image_square)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "disp = CameraDisplay(geom, image_1d)"
   ]
  }
 ],
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