similar to: NHW Project and wavelet codecs

Hello, I've found some time to get back to the NHW Project.In fact a Xiph forum member told me that even if I will start a new job, he hopes that I will still continue to develop a little the NHW Project, on my spare time.I told him that I would furthermore spend my spare time on the NHW Project if a community around the project could emerge... and he told me that certainly the best way for

Hello, I would like to discuss a little about the NHW codec and its state after nearly 5 years on the Xiph forums. I also know that if I would like to discuss I'd better go to the great Doom9 and Encode.ru forums but for now I find that my codec is too experimental for these professional forums: - the codec is only for fixed 512x512 size, just a test tool. - there is only mid compression -

I don't mind at all. I imagine there are more people like me out there who have been following your work, but haven't said anything. I agree that a series of pages explaining how things work may lead to more contributions. At the very least it would lead to more people being better educated on how wavelets work in image compression. But, this is your project, if you don't have the

Hello, I have just tested new next lower quality settings (-l3 and -l4), I can diminish residual coding but if I increase wavelet coeffs threshold there is more aliasing.And even in the current mid quality settings there is some aliasing, this is the big drawback of the NHW codec. SPIHT algorithm is good for that as for example Rududu codec doesn't have aliasing at all at mid compression and

Hello, So thanks to helpful forum feedbacks, I know now that I have to create a website for the NHW Project, make demo pages of the technology, and all that with good visual design.It won't be such easy for me... For example, I can easily supply a description, explanation of the different steps of the algorithm, I can supply images encoded at mid-compression with NHW, x265, WebP, JPEG,...

Hello, I have re-tested -l4 high compression setting and it's clear that it lacks of precision on degraded, rather blurred images. So I don't know if it is a good idea to base the other lower quality settings (-l5,-l6,...) on -l4 setting.I have tested the NHW codec against x265, x264, Daala, WebP, Rududu, DLI and it's clear that at high compression these very good codecs have more

Hi David! Many thanks for your very encouraging and kind feedback!!! (Hope you don't mind that I made your post public on the Theora channel). I try to be the more sincere as I can in my posts.Some people suggested me to make demo pages to explain how the codec works step by step, and I realize that it would be good, because certainly it will show that the NHW codec is not that complex and

Hello, I have some progress for the NHW codec. I recently talked with a researcher that has some interest in the NHW codec.He has studied several directional wavelet transforms (notably HWD directional transform), and he came to the conclusion that directional transforms will bring marginal improvement, not significant in the case of my compression codec.This also confirms what I have read from

Hello, Just a quick message to correct what I have said in my previous post.It finally seems not that easy to code small wavelet coefficients to have a good precision, and SPIHT is certainly a very good algorithm for that, -and I know there are SPIHT experts that can make very good SPIHT-based codecs-.I have chosen a new and different approach, the multistage residual coding, so I will try to

Hello, I have improved a little the NHW codec.I have improved the dequantization in the wavelet HH band, and little improved the -l2 (and lower) quality setting.I have also added a -l3 lower quality setting (-15Ko, exp), I have increased the quantization for this other setting, and I start to remove higher wavelet coefficients, but this is not optimal... The artifacts start to be noticeable for

Hello, Definitely not any (constructive) comments on the NHW Image codec? According to my tests, it can compare good with reference codecs like x264 intra and WebP. Yes, the codec is still experimental and is optimized for visual (subjective) evaluation, not PSNR.Its main feature is again that it would have a little more neatness/sharpness and a little less precision (residual coding is applied

Hello, I am still working on very high compression for the NHW Project, but I find the current version good, it has a good neatness of image, which I find visually more pleasant than other codecs that are optimizing for PSNR, SSIM,... Furthermore the NHW Project is still very fast and royalty-free. I dedicated this past year to the NHW Project and I could make very good improvements (like

Hello, So here is the compression scheme that I don't know if is covered by patent. I use it on the wavelet DC parts.It outputs 1 byte (8 bits) words.There is 5 modes: - 1(MSB) | 7 bits to store value (0->127 range) - 01 | 6 bits to store val[n+1]-val[n] | val[n]-val[n-1] if each in the range [-4,4] - 001 | 5 bits to store val[n+2]-val[n+1] | val[n+1]-val[n] | val[n]-val[n-1] if each in

Hello, I forgot in my last reply that my DWT implementation can be speed up, for example I'm doing for now: for (;_X1<_E_;_X1++,_RES+=2) //dilatation { _RES[0]=_X1[0]<<3; _RES[1]=(_X1[1]+_X1[0])<<2; } then for (;_X2<_E_;_X2++,_RES+=2) //details { _RES[0]-=(_X2[1]+_X2[0])<<1; _RES[1]+=6*_X2[1]-_X2[2]-_X2[0];

Hello all, Just a quick message for those interested in the NHW Project.I realize that I have too little time to spend on the project currently and I feel that this year will be very important after 6-7 years for its success or not.I already had some few replies from some companies (and a major one), and they can not spend some time, spend some engineers on my work because there is no

Hello, Ok, and that's too many work to review a source code.In my codec, I have 3 compression schemes, I think 2 are not patented, but the third... I don't know.For the rest, I think my codec is patent-free (I don't use SPIHT,EZW,zerotree methods), even the wavelet transform is new and don't use the lifting scheme nor the convolution product. Else, if you found time to review the

Hello, I am progressively getting back to the NHW Project development (but it is not that easy, I am a little depressed currently...). I realize what is needed for the NHW codec is more HF energy preservation, but as all the HF energy seems to require lot of bits, I wanted to select specifically the HF energy around blurred edges, in order not to have edges with aliasing.Is it possible to

Hello, I have finally added 2 lower quality settings for the NHW codec: -l1 (-5Ko) and -l2 (-10Ko).I use a quantization of 0.935 and 0.88 (kind of quantization), and I decrease residual coding on the first order wavelet image. I have updated the demo page: http://nhwcodec.blogspot.com/ . These 2 lower quality settings are still experimental.If you could find time, would be interested in any

Hello all, Finally find some time to get back to the NHW Project.I was thinking about making a technology demo, and I wanted to highlight the uniqueness of the NHW codec that is neatness/sharpness preserving or enhancement.With my eyes, I can see that the NHW codec has more neatness/sharpness than the other codecs (x265, x264, WebP, Rududu, JPEG,...), but for a demo there must be objective

Hello, I am still progressing with very high compression and I have corrected a processing, so now very high compression (-l10 to -l13 quality settings) has really better precision and so better quality. I have also released a first draft of a new -l14 very high compression quality setting. More at: http://nhwcodec.blogspot.com/ Just a remark, the entropy coding schemes start to be less