Questions tagged [deconvolution]

An algorithmic process to reverse the effects of a convolution, which is a linear form of signal or image filtering.

Deconvolution is the process of estimating an original signal (or image) from recorded data. Usually, the process of recording the signal involves a transfer function (in imaging, a point spread function), which is convolved with the original signal and blurs it. Deconvolution can then be applied to improve the signal quality. For example, in fluorescence microscopy deconvolution can be used together with special illumination configurations to obtain super-resolved images. If the transfer function cannot be measured, bind deconvolution can be used to estimate both the original signal and the transfer function simultaneously.

Deconvolution typically involves regularization and iterative optimization methods.


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What is the difference between UpSampling2D and Conv2DTranspose functions in keras?

Here in this code UpSampling2D and Conv2DTranspose seem to be used interchangeably. I want to know why this is happening. # u-net model with up-convolution or up-sampling and weighted binary-crossentropy as loss func from keras.models import…
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looking for source code of from gen_nn_ops in tensorflow

I am new to tensorflow for deep learning and interested in deconvolution (convolution transpose) operation in tensorflow. I need to take a look at the source code for operating deconvolution. The function is I guess conv2d_transpose() in…
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Understanding scipy deconvolve

I'm trying to understand scipy.signal.deconvolve. From the mathematical point of view a convolution is just the multiplication in fourier space so I would expect that for two functions f and g: Deconvolve(Convolve(f,g) , g) == f In numpy/scipy…
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What is the difference between performing upsampling together with strided transpose convolution and transpose convolution with stride 1 only?

I noticed in a number of places that people use something like this, usually in fully convolutional networks, autoencoders, and similar: model.add(UpSampling2D(size=(2,2))) model.add(Conv2DTranspose(kernel_size=k, padding='same', strides=(1,1)) I…
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TensorFlow: Unpooling

Is there TensorFlow native function that does unpooling for Deconvolutional Networks ? I have written this in normal python, but it is getting complicated when want to translate it to TensorFlow as it's objects does not even support item assignment…
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Tensorflow CNN training images are all different sizes

I have created a Deep Convolution Neural Network to classify individual pixels in an image. My training data will always be the same size (32x32x7), but my testing data can be any size. Github Repository Currently, my model will only work on images…
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How is using im2col operation in convolutional nets more efficient?

I am trying to implement a convolutional neural netwrok and I don't understand why using im2col operation is more efficient. It basically stores the input to be multiplied by filter in separate columns. But why shouldn't loops be used directly to…
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Deblurring an image

I am trying to deblur an image in Python but have run into some problems. Here is what I've tried, but keep in mind that I am not an expert on this topic. According to my understanding, if you know the point spread function, you should be able to…
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What output_padding does in nn.ConvTranspose2d?

What is the working of Output_padding in Conv2dTranspose? Please Help me to understand this? Conv2dTranspose(1024, 512, kernel_size=3, stride=2, padding=1, output_padding=1)
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Tensorflow Convolution Neural Network with different sized images

I am attempting to create a deep CNN that can classify each individual pixel in an image. I am replicating architecture from the image below taken from this paper. In the paper it is mentioned that deconvolutions are used so that any size of input…
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What does mask r-cnn's AP, AP50, AP70 mean?

I'm novice on r-cnn. There are term AP, AP50, AP75 on mask r-cnn paper. 50, 75 is small postfix, but I can't make it small, sorry. Anyway the paper says it is averaged over IOU thresholds. For AP50, only candidates over 50% region comparing ground…
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CNN: input stride vs. output stride

In the paper 'Fully Convolutional Networks for Semantic Segmentation' the author distinguishes between input stride and output stride in the context of deconvolution. How do these terms differ from each other?
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How to update the weights of a Deconvolutional Layer?

I'm trying to develop a deconvolutional layer (or a transposed convolutional layer to be precise). In the forward pass, I do a full convolution (convolution with zero padding) In the backward pass, I do a valid convolution (convolution without…
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Deconvolution2D layer in keras

This layer in not ready documented very well and I'm having a bit of trouble figuring out exactly how to use it. I'm Trying something like: input_img = Input(shape=(1, h, w)) x = Convolution2D(16, 7, 7, activation='relu',…
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Multichannel blind deconvolution in the simplest formulation: how to solve?

Recently I began to study deconvolution algorithms and met the following acquisition model: where f is the original (latent) image, g is the input (observed) image, h is the point spread function (degradation kernel), n is a random additive noise…
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