search for: rududu

...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 > > precision.But they also tend to blur/decrease neatness-sharpness of image > > where the NHW codec would enhance image neatness/sharpness.But that's > right > > that on degra...

...o not catch attention and don't have answers, but what is even harder is that I find the NHW codec still competitive (even in its current state). For example, I have made a visual comparison for mid compression (-l2 to -h2 setting) on 50 images of the NHW codec with BPG (HEVC intra), WebP, and Rududu Image Compression (Rududu is a powerful wavelet image codec, released in April 2008, that is based on SPIHT-like, zerotree coding, -it totally went under-the-radar...-). Results: The codec that has the more precision is BPG, the codec that has the more neatness is NHW.Don't know what is the be...

...ional wavelet transforms that would give improvement to the NHW codec, but are directional wavelets an active research field today? I have also seen some recent patents on advanced and improved SPIHT, and I am a little surprised that there is no "up-to-date" state-of-the-art wavelet codec.Rududu in April 2008 was the last advance in SPIHT research (but does not select directional wavelets) with very good results.If I remember the author post there is furthermore an interesting fast context modeling based on the 2x2 variance of wavelet coefficients in order to reduce the context cost per co...

...ext 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 then it appears slightly at high compression.So I will have to study it in details. The main advantage of the NHW codec is that it is very fast, but there is some aliasing, artifacts.The NHW Project after more than 7 years of existence...

...with it, do not hesitate to show up, it would be just great! I also have to keep on improving the NHW codec.Currently I am focusing on the aliasing of the NHW codec, it's the main drawback of the codec.I have certainly missed something because the other codecs AOM AV1, x265, x264, WebP, JPEG, Rududu (wavelet) don't create aliasing.-The NHW codec has other advantages.-This is certainly due to little HF energy preserving.If you have any suggestion, do not hesitate to let me know.I will also have to study more the SPIHT algorithm. Currently, I am more inclined to improve and develop NHW algo...

...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 precision.But they also tend to blur/decrease neatness-sharpness of image where the NHW codec would enhance image neatness/sharpness.But that's right that on degraded, blurred images where there is no neatness to...

...t; 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 >> > precision.But they also tend to blur/decrease neatness-sharpness of >> > image >> > where the NHW codec would enhance image neatness/sharpness.But that's...

...est 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 the Rududu author who tested directional wavelets in his codec without luck. I have potentially found a very good candidate for the YUV420 2x2 upsampling.I haven't studied the impact of this processing on the codec, but I believe that better downsampling and upsampling algorithms for U and V components w...

...o 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 metrics, and this is where things complicates.... I have tried to make quickly a neatness/sharpness metrics but without luck, and it doesn't seem that easy... Would someone of you have a neatness metrics? Would help me a lot for my technology...

...host on his server the NHW Project website, to present the codec on the embedded processors, MCU forums that he knows well, another member forked my GitHub repository!!! Really thank you very much!!! It makes me think that maybe the NHW Project will not disappear as many great projects before like Rududu codec, DLI compression, UCI codec (x264 intra) and others... -but these projects will maybe resurrect today-. There are some delay with the -l6 and lower quality settings because it is difficult to create good ones, that can compete with HEVC.But it would be so great to have some help from the com...

...65 (HEVC) on rather good quality images, because it has more neatness, but that's right that on "degraded" images (compressed, with artifacts), HEVC starts to excel and be very impressive. I find that -l13 very high compression setting is the limit where the other codecs (WebP, x264, Rududu,...) start to perform less efficiently and have noticeable quality drop, whereas HEVC stays excellent... I will try to improve the NHW Project so that it stays competitive with HEVC on all type of images at -l13 very high compression, and not on good quality only... but it is not that easy as I wan...

...good in fact at very high compression, it really preserves the contours, edges, and applies a rather strong denoising, details washing-out inside the contours.The resulting image can appear then a little "cartoonish" but visually it's the result I neatly prefer compared to x264, WebP, Rududu results and artifacts at these same very high compression ratios.(This is also confirmed by PSNR and SSIM...) So for -l8 very high compression setting and above, I will need to find a new approach of compression and perceptual quality, and new processings.Again if you have skills in image and sign...

...to present the codec >> on the embedded processors, MCU forums that he knows well, another member >> forked my GitHub repository!!! Really thank you very much!!! >> >> It makes me think that maybe the NHW Project will not disappear as many >> great projects before like Rududu codec, DLI compression, UCI codec (x264 >> intra) and others... -but these projects will maybe resurrect today-. >> >> There are some delay with the -l6 and lower quality settings because it >> is difficult to create good ones, that can compete with HEVC.But it would >&gt...

...to present the codec >> on the embedded processors, MCU forums that he knows well, another member >> forked my GitHub repository!!! Really thank you very much!!! >> >> It makes me think that maybe the NHW Project will not disappear as many >> great projects before like Rududu codec, DLI compression, UCI codec (x264 >> intra) and others... -but these projects will maybe resurrect today-. >> >> There are some delay with the -l6 and lower quality settings because it >> is difficult to create good ones, that can compete with HEVC.But it would >&gt...