I am working on the JPEG2000 compression as a part of my research work. I want some kind of open source libraries that can decode the JPEG2000 image and give me its DWT coefficients. And then I would like to encode these coefficients to get the image.
Thanks in advance
Related
we need to implement a yolov4 CNN application on FPGA. We would like to know the format of input and output tensors of Yolov4. Tried searching on the internet but could not find much info.
Can someone let me know the tensor formats for input and output? It will be great it someone can also give a link which gives this information along with architecture of yolov4 explained in detail.
regards,
-sunil
We are trying to detect certain actions on videos by concatenating together a few consecutive frames and training a machine learning model. Our trained model predicts perfectly when we read from a file (webm, VP09 if it matters) but when we read from a stream, the predictions are completely off.
Experimenting, we found that the incoming stream (h264) is in "Raw YUV" format. So we tried to convert the frames to RGB and then grayscale. The numpy array looks OK in that some grayscale values are consistent with those areas in the image but the predictions are still off.
Is it not possible to simply take concatenated frames from OpenCV's VideoCapture's read and use them? We are novices at video streams and codecs, so is there something obvious that we are missing? Thanks!
I would like to compare two video files for the file which is having a better quality (Non blurry) by a c programm.A friend told me to learn about DFT (Discrete Fourier Transform) for image analysis and to use a FFT or DFT tool to learn the difference between blurred vs detailed (non-blurry) copies of same image.So can anyone help me with this ??
You could also do this with SSIM or PSNR. Both can can be done in C and there are C++/C#/Cuda versions of these algorithms on the net.
Doug
I have a data set which form is matlab file.
The data set contains 600,000 samples and every sample is a matrix of 7-by-256.
My data is not image but signal.
I want to use CNN of caffe to train the data.
So how can I convert it to LMDB as my input of CNN.
I'm badly need the solution!
Converting data in matlab directly to lmdb might be a little tricky.
Why don't you try exporting your data to hdf5 binary files (supported both by matlab and caffe)?
Here is an answer describing how this can be done.
which Wavelet is used for Jpeg2000 Image Compression ?
I was reading the Book on Wavelet Transform to find out how wavelet works for image compression but there are so many types of Wavelets mentioned in the book and i am confused which one is used for Jpeg2000 compression ?
These are the types i've found in the book.
Biorthogonal wavelet, Shannon or “Sinc” wavelets , Haar wavelets (the shortest), Coiflets wavelets.
P.S: I've no knowledge of image compression , just starting it with this project.
According to the Wikipedia article on JPEG 2000, two different varieties of Cohen-Daubechies-Feauveau wavelet are used: the CDF 5/3 wavelet for lossless compression, and a CDF 9/7 wavelet for lossy compression. (Both sorts are biorthogonal.) See here: http://en.wikipedia.org/wiki/Cohen-Daubechies-Feauveau_wavelet .
Gareth
is correct that
CDF 9/7 wavelets
are used for lossy compression, but LGT (not CDF) 5/3 wavelets are used for lossless compression. See
this Wikipedia article
for more information on JPEG 2000 and
this blog
for more background on LGT 5/3 wavelets.