基于 TensorFlow 的图像识别(R实现)

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提到机器学习和深度学习,大家通常会想到Python,但R语言同样具备强大的实力。今天,我们将使用R语言展示一个基于TensorFlow的图像识别示例。如果你打算运行这些代码,首先需要安装并配置好TensorFlow,最好是在Linux系统上进行。

关于如何配置TensorFlow,建议参考官方文档,尽管文档是英文的,但却是最新且最准确的资源。

下面是具体的代码实现,其中包含了详细的注释,希望读者能够轻松理解:

```r

加载必要的库

library(tensorflow) library(magrittr)

导入slim库,简化神经网络的构建、训练和评估过程

slim <- tf$contrib$slim

清除默认图形,防止变量重复定义

tf$resetdefaultgraph()

创建一个占位符,用于存储输入的图像

images <- tf$placeholder(tf$float32, shape(NULL, NULL, NULL, 3))

将图像调整到224x224像素

imgsscaled <- tf$image$resizeimages(images, shape(224, 224))

开始构建VGG-16网络

fc8 <- imgsscaled %>% slim$conv2d(64, shape(3, 3), scope='vgg16/conv1/conv11') %>% slim$conv2d(64, shape(3, 3), scope='vgg16/conv1/conv12') %>% slim$maxpool2d(shape(2, 2), scope='vgg16/pool1') %>% slim$conv2d(128, shape(3, 3), scope='vgg16/conv2/conv21') %>% slim$conv2d(128, shape(3, 3), scope='vgg16/conv2/conv22') %>% slim$maxpool2d(shape(2, 2), scope='vgg16/pool2') %>% slim$conv2d(256, shape(3, 3), scope='vgg16/conv3/conv31') %>% slim$conv2d(256, shape(3, 3), scope='vgg16/conv3/conv32') %>% slim$conv2d(256, shape(3, 3), scope='vgg16/conv3/conv33') %>% slim$maxpool2d(shape(2, 2), scope='vgg16/pool3') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv4/conv41') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv4/conv42') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv4/conv43') %>% slim$maxpool2d(shape(2, 2), scope='vgg16/pool4') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv5/conv51') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv5/conv52') %>% slim$conv2d(512, shape(3, 3), scope='vgg16/conv5/conv53') %>% slim$maxpool2d(shape(2, 2), scope='vgg16/pool5') %>% slim$conv2d(4096, shape(7, 7), padding='VALID', scope='vgg16/fc6') %>% slim$conv2d(4096, shape(1, 1), scope='vgg16/fc7') %>% slim$conv2d(1000, shape(1, 1), scope='vgg16/fc8') %>% tf$squeeze(shape(1, 2), name='vgg_16/fc8/squeezed')

保存日志文件

tf$summary$FileWriter('/tmp/dumm/vgg16', tf$getdefaultgraph())$close()

创建Saver对象,用于管理模型中的所有变量

restorer <- tf$train$Saver()

创建会话并恢复模型参数

sess <- tf$Session() restorer$restore(sess, 'vgg_16.ckpt') ```

这段代码展示了如何使用R语言结合TensorFlow库来实现一个基于VGG-16模型的图像识别应用。通过这些步骤,你可以更直观地了解如何在R环境中进行深度学习相关的开发工作。

本文来源: 图灵汇 文章作者: 苏州博智慧达