similar to: Wavelet Image Codec - advice

Hi again, I have improved precision of my codec (on the encoder and decoder).I have also improved the -h1 quality setting.-Source code and binaries at http://nhwcodec.blogspot.com/-. I am still trying to improve precision of my codec, with keeping my low-complexity (fast) approach. I do not totally use the reference (and impressive) block prediction with different modes + residual coding scheme,

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, 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, 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 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, Just a very quick message to let you know that I have added a higher quality setting (-h2, +10Ko) and I have added now residual coding on the 512x256 wavelet image for the higher settings.Precision is a little better.-I also still apply the post-processing function on the 512x256 wavelet image for now.- Here is the link for the binaries (as I can not link them in my blog for now):

On Fri, 25 May 2012 14:00:01 -0500, <theora-request at xiph.org> wrote: > Message: 1 > Date: Fri, 25 May 2012 19:26:18 +0200 > From: Raphael Canut <nhwcodec at gmail.com> > Subject: [theora] NHW codec - improvement of precision > To: theora at xiph.org > Message-ID: > <CAKE58qHqSsrgJP4OX++eetMmT2WTv=8ZvfXoou7bWjOnbUSrAQ at mail.gmail.com> > Content-Type:

Hello, For those interested, I have added a -l8 "very high compression" setting to the NHW Project. I have added an experimental processing to remove details and preserve neatness.I have also now a fast estimation of entropy of wavelet coefficients and I use it accordingly to the image complexity but it is a very first version... With these new processings, the entropy coding schemes

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 don't have advanced on the NHW Project this past month, but I have definitely validated its characteristics and this new version. The NHW Codec preserves or enhances image neatness and sharpness, which translates that on good quality images the NHW Codec is globally better than HEVC, and on degraded (with blur, artifacts) images it is worse than HEVC because it lacks of precision. I

Raphael, Some 15 years ago I implemented limited functionality Theora in our cameras FPGA (it took me 6 month of hard labor), and then gave up - it is a very crowded space and it is difficult to compete with more advanced codecs. And for our other work we anyway need almost raw image data, so we are using JPEG-based JP4 format (https://community.elphel.com/jp4) that we originally developed for

Raphael, I do not believe it is possible to build a viable community around most hardware projects except super-universal based on very cheap/high-volume products like Pi or Arduino. We see the commercial benefits of Free Software/Open Hardware as it adds value to the hardware as users are ready to pay extra for the Freedom. Andrey ---- On Thu, 02 Dec 2021 12:59:34 -0700 Raphael Canut

Hi Andrey, Thank you for your answer.Actually, NHW is very low-power so I think it could be geared toward any hardware.But actually I don't have hardware skills, so NHW is not a real hardware project for now maybe? I agree with you that it is extremely difficult (for me) to build a community around NHW, I'm certainly very bad/underskilled at it.Any help is welcome! Cheers, Raphael Le

Following a post on vqf.com forum, I found out that some company called Adapted Wave Technology is ready to release its audio codec based on wavelets. They say that this wavelet-based codec is superior to MDCT codecs by 30-50%. One sentence caught my attention: "Adapted Wave Technologies holds exclusive patent rights for applying wavelet packets to audio applications." - sounds like a

Hello, I know there is no community around NHW, but I would have liked to know what you would like to see improved in the NHW codec.I know its results are not perfect for now compared to high-end AV1/VVC codecs for example, but could be ok giving its extremely fast speed.-However on high quality images, I notably like its good results because of its neatness.- Regarding things to improve, there

Hello, For those interested, I have added a -l4 high compression setting to the NHW codec ( http://nhwcodec.blogspot.com/ ).This setting is very experimental, I have boosted the sharpness for this one, but it can lack of precision on low contrast areas. This setting still maintains a good neatness and when it will be validated, I will then make a new 0.1.4 version for the NHW Project. High

You're welcome! On Tue, Jul 10, 2018, 4:50 AM Raphael Canut <nhwcodec at gmail.com> wrote: > Hello Dave, > > Thank you very much for your help! > > Cheers, > Raphael > > 2018-07-10 9:39 GMT+02:00 Dave Johnson Games <davefilms.us at gmail.com>: > >> Let me do some looking. >> >> On Mon, Jul 9, 2018, 4:55 PM Raphael Canut <nhwcodec at

Hello, In my last post, I seemed to say that there were no directional 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

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];

Dear, I am using "cwt "function from Rwave package to perform Morlet wavelet analysis. d1<-c(1.31673209591515, -0.171333455797346, -1.67618546079420, -0.931604651010362, -0.954614183224057, -1.19821794547758, 0.516096363353144, -0.0432811977638559, 0.737764943619919, 0.438046629673177, -0.208607167908743, -0.3091308821262, -1.42473112931594, 0.234125312118165, -0.307047554490597,