similar to: NHW Project - quality improvement - proper subband quantization

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 -

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, 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 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, 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, With -l5 quality setting, I have learned that I can increase wavelet coeff threshold to 12 in the HH band without noticeable difference in the reconstructed images.With this processing, I win in average 1Ko in the compressed .nhw files, and so I can raise the quantization for -l1->-l4 settings (0.935->0.955,0.88->0.9,0.87->0.89) and so these settings are now better, there is a

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

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

Hi Raphael, On Fri, Aug 25, 2017 at 2:30 PM, Raphael Canut <nhwcodec at gmail.com> wrote: > I'll see what Monty will do on his side (and when he has time), but he also > told me that the NHW codec has merits but there must be an effort to > demonstrate them. Well, if you want to pursue a collaborative project, you need to attract others to work on it. Perhaps 'demo'

Hello, These last 2 months, I have talked again with Monty Montgomery about the NHW Project and he told me that Xiph.org would like to encourage the NHW Project development.That's just great! I'll see what Monty will do on his side (and when he has time), but he also told me that the NHW codec has merits but there must be an effort to demonstrate them. The advantages, merits of the NHW

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, 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, I think I have nearly validated the -l8 "very high compression" setting, I have started to work on -l9 setting, and I have just tested these ones against x265 (HEVC), and on rather good quality images, they are very competitive, that's not a joke!!! I have tested -l8 quality setting on 30 rather good quality images against x265, and on 20-22 images I prefer the results of the

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 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, No advance for now on the NHW codec, I am still working on a new quantization scheme to scale down the compression ratios but without luck... Any advice, idea is very welcome.I will also have to correctly code the wavelet filerbank and process on rows and columns and suppress the image transposition (this is for long overdue)... will win few cycles... there are other parts to speed up (in

Hello all, It's me again.Just a quick message to tell that I finally do not agree that HEVC (don't have tested AOM AV1 for now) is better than the NHW codec at mid compression. Last night, I dowloaded 30 images of Star Wars Rogue One on the web and I made another comparison with x265 (HEVC) for mid compression (-l2 to h2 settings for the NHW codec). Visually, I prefer the results of NHW

Hello, I don't have advanced on the NHW codec, but now, as a lot of people, I am following the AOMedia AV1 codec.Just a (late) update of my previous post, there won't be problem in AOM AV1 with the CABAC scheme, as the codec will use Daala's multi-symbol entropy coder and/or ANS.That's great! I have even read on the wiki page, that AV1 will use Daala's PVQ as quantization

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 let you know that I have really improved very high compression of the NHW Project from -l8 to -l13 quality settings, and we can still save 2.5KB per .nhw compressed file. Actually I am new to very high compression, it is just 3 months that I am working on it (I put on pause the NHW Project from August 2013 to February 2018 )... And I realize that very high