|
15 | 15 | "cell_type": "markdown",
|
16 | 16 | "metadata": {},
|
17 | 17 | "source": [
|
18 |
| - "\n# Faces recognition example using eigenfaces and SVMs\n\nThe dataset used in this example is a preprocessed excerpt of the\n\"Labeled Faces in the Wild\", aka LFW_:\n\n http://vis-www.cs.umass.edu/lfw/lfw-funneled.tgz (233MB)\n\n\nExpected results for the top 5 most represented people in the dataset:\n\n================== ============ ======= ========== =======\n precision recall f1-score support\n================== ============ ======= ========== =======\n Ariel Sharon 0.67 0.92 0.77 13\n Colin Powell 0.75 0.78 0.76 60\n Donald Rumsfeld 0.78 0.67 0.72 27\n George W Bush 0.86 0.86 0.86 146\nGerhard Schroeder 0.76 0.76 0.76 25\n Hugo Chavez 0.67 0.67 0.67 15\n Tony Blair 0.81 0.69 0.75 36\n\n avg / total 0.80 0.80 0.80 322\n================== ============ ======= ========== =======\n" |
| 18 | + "\n# Faces recognition example using eigenfaces and SVMs\n\nThe dataset used in this example is a preprocessed excerpt of the\n\"Labeled Faces in the Wild\", aka LFW_:\n\n http://vis-www.cs.umass.edu/lfw/lfw-funneled.tgz (233MB)\n\n" |
19 | 19 | ]
|
20 | 20 | },
|
21 | 21 | {
|
|
26 | 26 | },
|
27 | 27 | "outputs": [],
|
28 | 28 | "source": [
|
29 |
| - "from time import time\nimport logging\nimport matplotlib.pyplot as plt\n\nfrom sklearn.model_selection import train_test_split\nfrom sklearn.model_selection import GridSearchCV\nfrom sklearn.datasets import fetch_lfw_people\nfrom sklearn.metrics import classification_report\nfrom sklearn.metrics import confusion_matrix\nfrom sklearn.decomposition import PCA\nfrom sklearn.svm import SVC\n\n\n# Display progress logs on stdout\nlogging.basicConfig(level=logging.INFO, format=\"%(asctime)s %(message)s\")\n\n\n# #############################################################################\n# Download the data, if not already on disk and load it as numpy arrays\n\nlfw_people = fetch_lfw_people(min_faces_per_person=70, resize=0.4)\n\n# introspect the images arrays to find the shapes (for plotting)\nn_samples, h, w = lfw_people.images.shape\n\n# for machine learning we use the 2 data directly (as relative pixel\n# positions info is ignored by this model)\nX = lfw_people.data\nn_features = X.shape[1]\n\n# the label to predict is the id of the person\ny = lfw_people.target\ntarget_names = lfw_people.target_names\nn_classes = target_names.shape[0]\n\nprint(\"Total dataset size:\")\nprint(\"n_samples: %d\" % n_samples)\nprint(\"n_features: %d\" % n_features)\nprint(\"n_classes: %d\" % n_classes)\n\n\n# #############################################################################\n# Split into a training set and a test set using a stratified k fold\n\n# split into a training and testing set\nX_train, X_test, y_train, y_test = train_test_split(\n X, y, test_size=0.25, random_state=42\n)\n\n\n# #############################################################################\n# Compute a PCA (eigenfaces) on the face dataset (treated as unlabeled\n# dataset): unsupervised feature extraction / dimensionality reduction\nn_components = 150\n\nprint(\n \"Extracting the top %d eigenfaces from %d faces\" % (n_components, X_train.shape[0])\n)\nt0 = time()\npca = PCA(n_components=n_components, svd_solver=\"randomized\", whiten=True).fit(X_train)\nprint(\"done in %0.3fs\" % (time() - t0))\n\neigenfaces = pca.components_.reshape((n_components, h, w))\n\nprint(\"Projecting the input data on the eigenfaces orthonormal basis\")\nt0 = time()\nX_train_pca = pca.transform(X_train)\nX_test_pca = pca.transform(X_test)\nprint(\"done in %0.3fs\" % (time() - t0))\n\n\n# #############################################################################\n# Train a SVM classification model\n\nprint(\"Fitting the classifier to the training set\")\nt0 = time()\nparam_grid = {\n \"C\": [1e3, 5e3, 1e4, 5e4, 1e5],\n \"gamma\": [0.0001, 0.0005, 0.001, 0.005, 0.01, 0.1],\n}\nclf = GridSearchCV(SVC(kernel=\"rbf\", class_weight=\"balanced\"), param_grid)\nclf = clf.fit(X_train_pca, y_train)\nprint(\"done in %0.3fs\" % (time() - t0))\nprint(\"Best estimator found by grid search:\")\nprint(clf.best_estimator_)\n\n\n# #############################################################################\n# Quantitative evaluation of the model quality on the test set\n\nprint(\"Predicting people's names on the test set\")\nt0 = time()\ny_pred = clf.predict(X_test_pca)\nprint(\"done in %0.3fs\" % (time() - t0))\n\nprint(classification_report(y_test, y_pred, target_names=target_names))\nprint(confusion_matrix(y_test, y_pred, labels=range(n_classes)))\n\n\n# #############################################################################\n# Qualitative evaluation of the predictions using matplotlib\n\n\ndef plot_gallery(images, titles, h, w, n_row=3, n_col=4):\n \"\"\"Helper function to plot a gallery of portraits\"\"\"\n plt.figure(figsize=(1.8 * n_col, 2.4 * n_row))\n plt.subplots_adjust(bottom=0, left=0.01, right=0.99, top=0.90, hspace=0.35)\n for i in range(n_row * n_col):\n plt.subplot(n_row, n_col, i + 1)\n plt.imshow(images[i].reshape((h, w)), cmap=plt.cm.gray)\n plt.title(titles[i], size=12)\n plt.xticks(())\n plt.yticks(())\n\n\n# plot the result of the prediction on a portion of the test set\n\n\ndef title(y_pred, y_test, target_names, i):\n pred_name = target_names[y_pred[i]].rsplit(\" \", 1)[-1]\n true_name = target_names[y_test[i]].rsplit(\" \", 1)[-1]\n return \"predicted: %s\\ntrue: %s\" % (pred_name, true_name)\n\n\nprediction_titles = [\n title(y_pred, y_test, target_names, i) for i in range(y_pred.shape[0])\n]\n\nplot_gallery(X_test, prediction_titles, h, w)\n\n# plot the gallery of the most significative eigenfaces\n\neigenface_titles = [\"eigenface %d\" % i for i in range(eigenfaces.shape[0])]\nplot_gallery(eigenfaces, eigenface_titles, h, w)\n\nplt.show()" |
| 29 | + "from time import time\nimport matplotlib.pyplot as plt\n\nfrom sklearn.model_selection import train_test_split\nfrom sklearn.model_selection import RandomizedSearchCV\nfrom sklearn.datasets import fetch_lfw_people\nfrom sklearn.metrics import classification_report\nfrom sklearn.metrics import ConfusionMatrixDisplay\nfrom sklearn.preprocessing import StandardScaler\nfrom sklearn.decomposition import PCA\nfrom sklearn.svm import SVC\nfrom sklearn.utils.fixes import loguniform" |
| 30 | + ] |
| 31 | + }, |
| 32 | + { |
| 33 | + "cell_type": "markdown", |
| 34 | + "metadata": {}, |
| 35 | + "source": [ |
| 36 | + "Download the data, if not already on disk and load it as numpy arrays\n\n" |
| 37 | + ] |
| 38 | + }, |
| 39 | + { |
| 40 | + "cell_type": "code", |
| 41 | + "execution_count": null, |
| 42 | + "metadata": { |
| 43 | + "collapsed": false |
| 44 | + }, |
| 45 | + "outputs": [], |
| 46 | + "source": [ |
| 47 | + "lfw_people = fetch_lfw_people(min_faces_per_person=70, resize=0.4)\n\n# introspect the images arrays to find the shapes (for plotting)\nn_samples, h, w = lfw_people.images.shape\n\n# for machine learning we use the 2 data directly (as relative pixel\n# positions info is ignored by this model)\nX = lfw_people.data\nn_features = X.shape[1]\n\n# the label to predict is the id of the person\ny = lfw_people.target\ntarget_names = lfw_people.target_names\nn_classes = target_names.shape[0]\n\nprint(\"Total dataset size:\")\nprint(\"n_samples: %d\" % n_samples)\nprint(\"n_features: %d\" % n_features)\nprint(\"n_classes: %d\" % n_classes)" |
| 48 | + ] |
| 49 | + }, |
| 50 | + { |
| 51 | + "cell_type": "markdown", |
| 52 | + "metadata": {}, |
| 53 | + "source": [ |
| 54 | + "Split into a training set and a test and keep 25% of the data for testing.\n\n" |
| 55 | + ] |
| 56 | + }, |
| 57 | + { |
| 58 | + "cell_type": "code", |
| 59 | + "execution_count": null, |
| 60 | + "metadata": { |
| 61 | + "collapsed": false |
| 62 | + }, |
| 63 | + "outputs": [], |
| 64 | + "source": [ |
| 65 | + "X_train, X_test, y_train, y_test = train_test_split(\n X, y, test_size=0.25, random_state=42\n)\n\nscaler = StandardScaler()\nX_train = scaler.fit_transform(X_train)\nX_test = scaler.transform(X_test)" |
| 66 | + ] |
| 67 | + }, |
| 68 | + { |
| 69 | + "cell_type": "markdown", |
| 70 | + "metadata": {}, |
| 71 | + "source": [ |
| 72 | + "Compute a PCA (eigenfaces) on the face dataset (treated as unlabeled\ndataset): unsupervised feature extraction / dimensionality reduction\n\n" |
| 73 | + ] |
| 74 | + }, |
| 75 | + { |
| 76 | + "cell_type": "code", |
| 77 | + "execution_count": null, |
| 78 | + "metadata": { |
| 79 | + "collapsed": false |
| 80 | + }, |
| 81 | + "outputs": [], |
| 82 | + "source": [ |
| 83 | + "n_components = 150\n\nprint(\n \"Extracting the top %d eigenfaces from %d faces\" % (n_components, X_train.shape[0])\n)\nt0 = time()\npca = PCA(n_components=n_components, svd_solver=\"randomized\", whiten=True).fit(X_train)\nprint(\"done in %0.3fs\" % (time() - t0))\n\neigenfaces = pca.components_.reshape((n_components, h, w))\n\nprint(\"Projecting the input data on the eigenfaces orthonormal basis\")\nt0 = time()\nX_train_pca = pca.transform(X_train)\nX_test_pca = pca.transform(X_test)\nprint(\"done in %0.3fs\" % (time() - t0))" |
| 84 | + ] |
| 85 | + }, |
| 86 | + { |
| 87 | + "cell_type": "markdown", |
| 88 | + "metadata": {}, |
| 89 | + "source": [ |
| 90 | + "Train a SVM classification model\n\n" |
| 91 | + ] |
| 92 | + }, |
| 93 | + { |
| 94 | + "cell_type": "code", |
| 95 | + "execution_count": null, |
| 96 | + "metadata": { |
| 97 | + "collapsed": false |
| 98 | + }, |
| 99 | + "outputs": [], |
| 100 | + "source": [ |
| 101 | + "print(\"Fitting the classifier to the training set\")\nt0 = time()\nparam_grid = {\n \"C\": loguniform(1e3, 1e5),\n \"gamma\": loguniform(1e-4, 1e-1),\n}\nclf = RandomizedSearchCV(\n SVC(kernel=\"rbf\", class_weight=\"balanced\"), param_grid, n_iter=10\n)\nclf = clf.fit(X_train_pca, y_train)\nprint(\"done in %0.3fs\" % (time() - t0))\nprint(\"Best estimator found by grid search:\")\nprint(clf.best_estimator_)" |
| 102 | + ] |
| 103 | + }, |
| 104 | + { |
| 105 | + "cell_type": "markdown", |
| 106 | + "metadata": {}, |
| 107 | + "source": [ |
| 108 | + "Quantitative evaluation of the model quality on the test set\n\n" |
| 109 | + ] |
| 110 | + }, |
| 111 | + { |
| 112 | + "cell_type": "code", |
| 113 | + "execution_count": null, |
| 114 | + "metadata": { |
| 115 | + "collapsed": false |
| 116 | + }, |
| 117 | + "outputs": [], |
| 118 | + "source": [ |
| 119 | + "print(\"Predicting people's names on the test set\")\nt0 = time()\ny_pred = clf.predict(X_test_pca)\nprint(\"done in %0.3fs\" % (time() - t0))\n\nprint(classification_report(y_test, y_pred, target_names=target_names))\nConfusionMatrixDisplay.from_estimator(\n clf, X_test_pca, y_test, display_labels=target_names, xticks_rotation=\"vertical\"\n)\nplt.tight_layout()\nplt.show()" |
| 120 | + ] |
| 121 | + }, |
| 122 | + { |
| 123 | + "cell_type": "markdown", |
| 124 | + "metadata": {}, |
| 125 | + "source": [ |
| 126 | + "Qualitative evaluation of the predictions using matplotlib\n\n" |
| 127 | + ] |
| 128 | + }, |
| 129 | + { |
| 130 | + "cell_type": "code", |
| 131 | + "execution_count": null, |
| 132 | + "metadata": { |
| 133 | + "collapsed": false |
| 134 | + }, |
| 135 | + "outputs": [], |
| 136 | + "source": [ |
| 137 | + "def plot_gallery(images, titles, h, w, n_row=3, n_col=4):\n \"\"\"Helper function to plot a gallery of portraits\"\"\"\n plt.figure(figsize=(1.8 * n_col, 2.4 * n_row))\n plt.subplots_adjust(bottom=0, left=0.01, right=0.99, top=0.90, hspace=0.35)\n for i in range(n_row * n_col):\n plt.subplot(n_row, n_col, i + 1)\n plt.imshow(images[i].reshape((h, w)), cmap=plt.cm.gray)\n plt.title(titles[i], size=12)\n plt.xticks(())\n plt.yticks(())" |
| 138 | + ] |
| 139 | + }, |
| 140 | + { |
| 141 | + "cell_type": "markdown", |
| 142 | + "metadata": {}, |
| 143 | + "source": [ |
| 144 | + "plot the result of the prediction on a portion of the test set\n\n" |
| 145 | + ] |
| 146 | + }, |
| 147 | + { |
| 148 | + "cell_type": "code", |
| 149 | + "execution_count": null, |
| 150 | + "metadata": { |
| 151 | + "collapsed": false |
| 152 | + }, |
| 153 | + "outputs": [], |
| 154 | + "source": [ |
| 155 | + "def title(y_pred, y_test, target_names, i):\n pred_name = target_names[y_pred[i]].rsplit(\" \", 1)[-1]\n true_name = target_names[y_test[i]].rsplit(\" \", 1)[-1]\n return \"predicted: %s\\ntrue: %s\" % (pred_name, true_name)\n\n\nprediction_titles = [\n title(y_pred, y_test, target_names, i) for i in range(y_pred.shape[0])\n]\n\nplot_gallery(X_test, prediction_titles, h, w)" |
| 156 | + ] |
| 157 | + }, |
| 158 | + { |
| 159 | + "cell_type": "markdown", |
| 160 | + "metadata": {}, |
| 161 | + "source": [ |
| 162 | + "plot the gallery of the most significative eigenfaces\n\n" |
| 163 | + ] |
| 164 | + }, |
| 165 | + { |
| 166 | + "cell_type": "code", |
| 167 | + "execution_count": null, |
| 168 | + "metadata": { |
| 169 | + "collapsed": false |
| 170 | + }, |
| 171 | + "outputs": [], |
| 172 | + "source": [ |
| 173 | + "eigenface_titles = [\"eigenface %d\" % i for i in range(eigenfaces.shape[0])]\nplot_gallery(eigenfaces, eigenface_titles, h, w)\n\nplt.show()" |
| 174 | + ] |
| 175 | + }, |
| 176 | + { |
| 177 | + "cell_type": "markdown", |
| 178 | + "metadata": {}, |
| 179 | + "source": [ |
| 180 | + "Face recognition problem would be much more effectively solved by training\nconvolutional neural networks but this family of models is outside of the scope of\nthe scikit-learn library. Interested readers should instead try to use pytorch or\ntensorflow to implement such models.\n\n" |
30 | 181 | ]
|
31 | 182 | }
|
32 | 183 | ],
|
|
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