5_Gray_img_denoise.ipynb

{"nbformat":4,"nbformat_minor":0,"metadata":{"colab":{"provenance":[],"mount_file_id":"148avQOP_yupuCfXY_ghYCQM7JzrTiBc_","authorship_tag":"ABX9TyMWxPpKqyjvJ2q/Mrbqmih8"},"kernelspec":{"name":"python3","display_name":"Python 3"},"language_info":{"name":"python"}},"cells":[{"cell_type":"code","execution_count":34,"metadata":{"id":"YO4wcpAAAY6b","executionInfo":{"status":"ok","timestamp":1700523823098,"user_tz":-60,"elapsed":239,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"outputs":[],"source":["import matplotlib.pyplot as plt\n","from skimage.restoration import (denoise_wavelet, estimate_sigma)\n","from skimage.util import random_noise\n","from skimage.metrics import peak_signal_noise_ratio\n","import skimage.io\n","\n","import warnings\n","warnings.filterwarnings('ignore')"]},{"cell_type":"code","source":["img = skimage.io.imread('/content/drive/MyDrive/FWT_data/lena.bmp')\n","img = skimage.img_as_float(img) # converting image as float"],"metadata":{"id":"TRDeFkCdAz-p","executionInfo":{"status":"ok","timestamp":1700523823349,"user_tz":-60,"elapsed":2,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":35,"outputs":[]},{"cell_type":"code","source":["sigma = 0.1 # Noise standard deviation\n","imgn = random_noise(img, var = sigma**2) # adding noise"],"metadata":{"id":"TC62Rn-MA-Eq","executionInfo":{"status":"ok","timestamp":1700523823349,"user_tz":-60,"elapsed":2,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":36,"outputs":[]},{"cell_type":"code","source":["sigma_est = estimate_sigma(imgn, average_sigmas = True) # noise estimation"],"metadata":{"id":"KU1FSgPRBNTZ","executionInfo":{"status":"ok","timestamp":1700523823715,"user_tz":-60,"elapsed":368,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":37,"outputs":[]},{"cell_type":"code","source":["# Denoising using Bayes\n","img_bayes = denoise_wavelet(imgn,\n","                            method = 'BayesShrink',\n","                            mode = 'soft',\n","                            wavelet_levels = 3,\n","                            wavelet = 'bior6.8',\n","                            rescale_sigma = True)"],"metadata":{"id":"YjE0gNCDBV1K","executionInfo":{"status":"ok","timestamp":1700523823716,"user_tz":-60,"elapsed":3,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":38,"outputs":[]},{"cell_type":"code","source":["# Denoising using Visushrink\n","img_visushrink = denoise_wavelet(imgn,\n","                                 method = 'VisuShrink',\n","                                 mode = 'soft',\n","                                 sigma = sigma_est/3,\n","                                 wavelet_levels = 5,\n","                                 wavelet = 'bior6.8',\n","                                 rescale_sigma = True)"],"metadata":{"id":"3Y_p9ym_BmaD","executionInfo":{"status":"ok","timestamp":1700523823945,"user_tz":-60,"elapsed":232,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":39,"outputs":[]},{"cell_type":"code","source":["# Finding PSNR\n","psnr_noisy = peak_signal_noise_ratio(img, imgn)\n","psnr_bayes = peak_signal_noise_ratio(img, img_bayes)\n","psnr_visu = peak_signal_noise_ratio(img, img_visushrink)"],"metadata":{"id":"jXx-JXpVCJgW","executionInfo":{"status":"ok","timestamp":1700523823946,"user_tz":-60,"elapsed":6,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":40,"outputs":[]},{"cell_type":"code","source":["plt.figure(figsize = (30, 30))\n","\n","plt.subplot(2, 2, 1)\n","plt.imshow(img, cmap = plt.cm.gray)\n","plt.title('Original image', fontsize = 30)\n","\n","plt.subplot(2, 2, 2)\n","plt.imshow(imgn, cmap = plt.cm.gray)\n","plt.title('Noisy image', fontsize = 30)\n","\n","plt.subplot(2, 2, 3)\n","plt.imshow(img_bayes, cmap = plt.cm.gray)\n","plt.title('Denoised image using Bayes', fontsize = 30)\n","\n","plt.subplot(2, 2, 4)\n","plt.imshow(img_visushrink, cmap = plt.cm.gray)\n","plt.title('Denoised image using VisuShrink', fontsize = 30)\n","\n","plt.show()"],"metadata":{"colab":{"base_uri":"https://localhost:8080/","height":652,"output_embedded_package_id":"1rDKBzdIr68YceMuSFNo61cNqDnLkac9X"},"id":"1nKCjZ_bCgU5","executionInfo":{"status":"ok","timestamp":1700523831813,"user_tz":-60,"elapsed":7872,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}},"outputId":"9744bdda-c0f7-42f5-c7a1-52e7b7cd34ee"},"execution_count":41,"outputs":[{"output_type":"display_data","data":{"text/plain":"Output hidden; open in https://colab.research.google.com to view."},"metadata":{}}]},{"cell_type":"code","source":["print('PSNR (Original vs. Noisy image = ', psnr_noisy)\n","print('PSNR (Original vs. Denoised (VisuShrink) = ', psnr_visu)\n","print('PSNR (Original vs. Denoised (Bayes) = ', psnr_bayes)"],"metadata":{"colab":{"base_uri":"https://localhost:8080/"},"id":"gcq2GevYDJKt","executionInfo":{"status":"ok","timestamp":1700523831813,"user_tz":-60,"elapsed":8,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}},"outputId":"eede6ded-2621-4371-f53e-37a6dd9c2e79"},"execution_count":42,"outputs":[{"output_type":"stream","name":"stdout","text":["PSNR (Original vs. Noisy image =  20.08342220096964\n","PSNR (Original vs. Denoised (VisuShrink) =  28.14414205733516\n","PSNR (Original vs. Denoised (Bayes) =  28.99376335153445\n"]}]},{"cell_type":"code","source":[],"metadata":{"id":"1bam4YJUDstB","executionInfo":{"status":"ok","timestamp":1700523831814,"user_tz":-60,"elapsed":6,"user":{"displayName":"Sachin Bharadwaj Manjunath","userId":"16663052345521703125"}}},"execution_count":42,"outputs":[]}]}