Displaying 20 results from an estimated 8000 matches similar to: "NHW Project - high compression - aliasing"
2018 Aug 17
2
NHW Project - new -l8 "very high compression" setting
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
2013 Jun 19
0
NHW Image codec - lower quality settings
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
2018 Aug 19
0
NHW Project - new -l8 "very high compression" setting
Hello,
The -l8 "very high compression" setting I posted was not really good.Now I
have corrected and improved it, and now the -l8 quality setting is really
better, more precision and more neatness.
I think now it is a good setting, and I have started to compare it with
x265 and it can be now competitive.
More at: http://nhwcodec.blogspot.com/
Do not hesitate to test it and give me
2013 May 29
1
NHW Image codec - 2 lower quality settings
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
2018 Feb 18
1
NHW Project - high compression -l4 setting
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
2018 Mar 10
0
NHW Project - lower quality settings
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
2018 Aug 22
0
NHW Project - very high compression settings
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
2017 Sep 04
0
NHW Project - fast discrete wavelet transform
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];
2018 Mar 10
2
NHW Project - lower quality settings
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
2017 May 27
0
NHW Codec - aliasing
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
2016 Oct 01
0
NHW codec
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
-
2018 Dec 12
0
NHW Project - good quality improvement & new -l14 very high compression quality setting
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
2012 Jul 25
4
NHW Image codec - improvement of precision
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,
2018 Dec 10
0
NHW Project - good improvement of very high compression (-l8 to -l13 quality settings)
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
2021 Dec 02
1
NHW Project development
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
2021 Dec 02
1
NHW Project development
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
2021 Dec 02
1
NHW Project development
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
2017 Aug 25
4
NHW Project - news with Xiph.org
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
2017 Aug 30
0
NHW Project - news with Xiph.org
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'
2013 Aug 28
0
NHW Image codec - Compression Performance
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