x265 - Work already started?

[Atak_Snajpera]

Which doesn't change the fact, that these artifacts would probably never have occurred with a proper 10-Bit (or even higher) encode.

will it require higher bitrate ? will HEVC support 10 bit+ by default? Or this is gonna be again part of HIGHER PROFILE?

[LoRd_MuldeR]

Originally Posted by Atak_Snajpera

will it require higher bitrate ? will HEVC support 10 bit+ by default? Or this is gonna be again part of HIGHER PROFILE?

Nope. Higher bit-depth does not necessarily imply a higher bit-rate.

In fact, with higher internal precision (bit-depth) you can achieve a higher compression efficiency and thus might be able to get away with a lower bit-rate for the same level of quality. Even for 8-Bit sources.

Using "only" 8-Bit internal precision primarily is a speed hack. If at all, the speed may be the problem, why they not use a higher bit-depth by default. But if they make a new format, we will need new h/w decoders anyway. So they might choose a higher bit-depth right from the start

[IgorC]

HEVC will have a higher internal bit depth http://www.h265.net/2010/11/analysis...-overview.html

[Atak_Snajpera]

I've added 10 bit screenshot for comparison
http://forum.doom9.org/showthread.ph...04#post1560604

8bit + deband filter looks like 10bit for me

[chenm001]

Oh, so many people concern HEVC.
My project THEVC is a simple(or call baseline) software model, I drop many of features, it is let us easy to read.
The x265 is opensource and powerful implement.

I am looking for a new job since last year, so I am have a little time, but I am still working on it.
I hope that I can release a IDR only version before Apr 2012, then I will doing a new plan, use GPU speedup or working on P-Slice?

In my plan for the IDR only version, the LCU 64x64, Transform 32x32, IntraPred, Cabac implement in the first version, and QuadTree split, SAO implement late, the deblock and ALF maybe drop in this year, because them have lower compress performance.

btw:
The project status I will update on x265 project homepage every month.
Any ideas can send to my email at 163.com.

[dansrfe]

Is there a current H.264 encoder that can leverage the GPUs via CUDA or OpenCL as well as the CPUs in a customized way? I'm very interested in something like that.

[manma]

Originally Posted by dansrfe

Is there a current H.264 encoder that can leverage the GPUs via CUDA or OpenCL as well as the CPUs in a customized way? I'm very interested in something like that.

From what I can gather, hardware vendor specific APIs like DXVA and CUVID are too limited, and rewriting x264 to use things like OpenCL is too difficult/time consuming/not worth the payoff. One thing that I can say for sure though is that there's no real technical limitation. Time is the real issue.

[chenm001]

Originally Posted by manma

From what I can gather, hardware vendor specific APIs like DXVA and CUVID are too limited, and rewriting x264 to use things like OpenCL is too difficult/time consuming/not worth the payoff. One thing that I can say for sure though is that there's no real technical limitation. Time is the real issue.

I agree with you.
There is not technical difficulty, the only one is time.
The codec architecture must suit to GPU, but we need many time to experiment.

[chenm001]

I have been upload source yesterday.

[Amdh]

Originally Posted by chenm001

I have been upload source yesterday.

I've just noticed that, thanks for your efforts.
Could you please compile a version for use in CLI mode ?

[chenm001]

Originally Posted by Amdh

I've just noticed that, thanks for your efforts.
Could you please compile a version for use in CLI mode ?

OK, I have been upload a command line execure, it running on Windows.

[Amdh]

Originally Posted by chenm001

OK, I have been upload a command line execure, it running on Windows.

Thanks, I really appreciate it

[uneedme]

how did it work?

which input file format could be accepted?......

[chenm001]

Originally Posted by uneedme

how did it work?

which input file format could be accepted?......

It is accept YUV420 only, I am plan integrate into libavcodec when I have the time, so you can use any input late.

[LigH]

For the german readers, the c't magazine issue 14/2012 explains H.265 a bit more detailed.

[IgorC]

http://multimediacommunication.blogs...h-meeting.html

N12475 is the Report on preliminary subjective testing of HEVC compression capability which can be found here. It shows impressive results as reported elsewhere, e.g., here. In particular, > 50% bitrate reduction, 67% in class B (HDTV), 49% in class C (WVGA) => mission accomplished!

https://dl.dropbox.com/u/1346434/w12475.zip

[Dust Signs]

Originally Posted by LigH

For the german readers, the c't magazine issue 14/2012 explains H.265 a bit more detailed.

I saw this on the cover and bought it and I must say that it contains a lot of (new) information (at least for me). Unfortunately, nearly all of the special vocabulary (i.e. words like intra prediction) have been translated to German which makes the article very hard to read. It is still quite a good summary, though.

Best regards
Dust Signs

[LoRd_MuldeR]

In the latest issue of c't magazine somebody complained that the "Main" profile of HEVC won't support higher bit-depths than 8-Bit.

They replied that the SAO (Sample Adaptive Offset) feature will practically eliminate banding, even at 8-Bit. I wonder if this really holds up in reality

[spawnbsd]

Originally Posted by LoRd_MuldeR

In the latest issue of c't magazine somebody complained that the "Main" profile of HEVC won't support higher bit-depths than 8-Bit.

They replied that the SAO (Sample Adaptive Offset) feature will practically eliminate banding, even at 8-Bit. I wonder if this really holds up in reality

That is true for "Main" profile, but if I recall correctly the "High Efficiency" profile supports 12bit internal precision; even with 8bit source content.

[LoRd_MuldeR]

Originally Posted by spawnbsd

That is true for "Main" profile, but if I recall correctly the "High Efficiency" profile supports 12bit internal precision; even with 8bit source content.

Yup, but the first official specification of HEVC will be "Main" profile only. More profiles are to be added at a later time. We'll see which profile is going to be commonly supported...