vp9 multithread is not working

[abo...@gmail.com]

Hi

vp9 uses one thread only no matter what number of threads are set. This problem make vp9 slower than vp8 if multi-thread option is used.
vp8 multi-thread works fine on my system while vp9 does not even thought the parameter is set (i.e. -t 8). vp9 encoder parameter:  g_threads = 8

System: ubuntu 12.04 LTS 64-bit
Processor: Intel® Core™ i7-2600 CPU @ 3.40GHz × 8

Has anyone run into the same issue?

Thank you

[Ronald S. Bultje]

Hi,

we haven't implemented multithreading support in VP9 yet. The bitstream has provisions for it, it just hasn't been implemented yet.

Ronald

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[abo...@gmail.com]

Thank you for the clarification.

[pswamy...@gmail.com]

Ronald,

Any update on multithreading support in VP9. ? I went thro the code. It doesn't seem to be there. What is the plan and tentative deadline for this support?

And when the support comes, will it be across tiles.?

Regards

Naveen

[James Zern]

On Mon, Aug 5, 2013 at 11:07 PM, <pswamy...@gmail.com> wrote:
> Ronald,
>
> Any update on multithreading support in VP9. ? I went thro the code. It
> doesn't seem to be there. What is the plan and tentative deadline for this
> support?

I recently added threading for the loop filter:
a0ffa27 vp9/decoder: threaded row-based loop filter

Multi-frame decoding may be added, but I don't really have a time
frame for that.

> And when the support comes, will it be across tiles.?
>

The worker style used with the loop filter could be re-used for tiles,
but note some modifications would be necessary as the loop filter
itself expects to operate on the fully reconstructed frame.

[j.kart...@gmail.com]

James,

Is there a plan to do multithreading for reconstruction, Intra prediction and Motion compensation(within a single frame) as well?

regards,

Karthick

[James Zern]

On Tue, Aug 6, 2013 at 10:21 PM, <j.kart...@gmail.com> wrote:
> James,
>
> Is there a plan to do multithreading for reconstruction, Intra prediction
> and Motion compensation(within a single frame) as well?
>

There's definitely more that can be done within a single frame, so
these are open for exploration.

[kurt...@gmail.com]

Hi,

Any news regarding VP9 multithreading support for the encoder ? Is it plan for VP10 or not ?

Regards,

[Anil]

Hi,

I had the same question for encoder. I am running on a Nexus 5. 

By adjusting the cpu-used parameter, the encoder runs over 40fps for WVGA sequences.

But the quality is quite bad. It uses only one core. 

If it supported multi-core, either quality could be improved, or higher resolutions can be supported

I saw some decoder multi-threading support being added as per git logs

Is there any plan to add multi-threading support for encoder as well?

Thanks

Anil

[Yunqing Wang]

FYI

VP9 multi-threaded encoder works now, which is based on the multi-tile feature in VP9. The number of threads is no more than the number of column tiles. In VP9, the minimum tile width is 256. Then, to run multi-threaded encoder(vpxenc), add encoding options:

  for videos with frame width >=512, use "--tile-columns=1 -t 2";

  for videos with frame width >= 1024, use "--tile-columns=2 -t 4";

  for videos with frame width >= 2048, use "--tile-columns=3 -t 8".

Yunqing

[Anil]

Sorry, My mistake. I forgot to add "--tile-columns".

Multi-thread encoding works fine now

Thanks

Anil

[Mustafa Muhammad]

On Wed, Jan 28, 2015 at 3:05 AM, Yunqing Wang <yunqi...@google.com> wrote:
> FYI
>
> VP9 multi-threaded encoder works now, which is based on the multi-tile
> feature in VP9. The number of threads is no more than the number of column
> tiles. In VP9, the minimum tile width is 256. Then, to run multi-threaded
> encoder(vpxenc), add encoding options:
> for videos with frame width >=512, use "--tile-columns=1 -t 2";
> for videos with frame width >= 1024, use "--tile-columns=2 -t 4";
> for videos with frame width >= 2048, use "--tile-columns=3 -t 8".
>
> Yunqing
>

Thank you for this info, I am wondering, does using multi-threading
affect output quality?

Also in "--tile-columns=1 -t 2" what does the "-t 2" represents? I
only saw VP9_DASH_PARAMS="-tile-columns 4 -frame-parallel 1"
in:
http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash

Where I can find more docs about this?

Thank you very much

> On Wednesday, June 26, 2013 at 1:10:22 PM UTC-7, abo...@gmail.com wrote:
>>
>> Hi
>>
>> vp9 uses one thread only no matter what number of threads are set. This
>> problem make vp9 slower than vp8 if multi-thread option is used.
>> vp8 multi-thread works fine on my system while vp9 does not even thought
>> the parameter is set (i.e. -t 8). vp9 encoder parameter: g_threads = 8
>>
>> System: ubuntu 12.04 LTS 64-bit
>> Processor: Intel® Core™ i7-2600 CPU @ 3.40GHz × 8
>>
>> Has anyone run into the same issue?
>>
>> Thank you
>

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> For more options, visit

> https://groups.google.com/a/webmproject.org/d/optout.

[Mustafa Muhammad]

On Tue, Mar 3, 2015 at 2:45 PM, Mustafa Muhammad
<mustafaa....@gmail.com> wrote:
> On Wed, Jan 28, 2015 at 3:05 AM, Yunqing Wang <yunqi...@google.com> wrote:
>> FYI
>>
>> VP9 multi-threaded encoder works now, which is based on the multi-tile
>> feature in VP9. The number of threads is no more than the number of column
>> tiles. In VP9, the minimum tile width is 256. Then, to run multi-threaded
>> encoder(vpxenc), add encoding options:
>> for videos with frame width >=512, use "--tile-columns=1 -t 2";
>> for videos with frame width >= 1024, use "--tile-columns=2 -t 4";
>> for videos with frame width >= 2048, use "--tile-columns=3 -t 8".
>>
>> Yunqing
>>
>
> Thank you for this info, I am wondering, does using multi-threading
> affect output quality?
>
> Also in "--tile-columns=1 -t 2" what does the "-t 2" represents? I
> only saw VP9_DASH_PARAMS="-tile-columns 4 -frame-parallel 1"
> in:
> http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash
>
> Where I can find more docs about this?
>
> Thank you very much

I understood the "-t" is for threads, now the question: Does
"-tile-columns and -frame-parallel" affect the output quality? As I
understood they both can be used for multi-threading, what about
"-tile-rows"?

Thank you
Mustafa

[Yunqing Wang]

VP9 doesn't support independent row tiles, the multi-threaded encoder uses independent column tiles. So you don't need to set "-tile-rows". "-tile-columns" always needs to be set, and it does affect the output quality slightly. There was some changes regarding using of "-frame-parallel". "-frame-parallel=1" was required before in order to do multi-thread encoding/decoding, but wasn't required anymore if you check out the newest libvpx code. "-frame-parallel=1" also affects the output quality.

Yunqing

[Mustafa Muhammad]

On Tue, Mar 3, 2015 at 7:55 PM, 'Yunqing Wang' via Codec Developers
<codec...@webmproject.org> wrote:
> VP9 doesn't support independent row tiles, the multi-threaded encoder uses
> independent column tiles. So you don't need to set "-tile-rows".
> "-tile-columns" always needs to be set, and it does affect the output
> quality slightly. There was some changes regarding using of
> "-frame-parallel". "-frame-parallel=1" was required before in order to do
> multi-thread encoding/decoding, but wasn't required anymore if you check out
> the newest libvpx code. "-frame-parallel=1" also affects the output quality.
>
> Yunqing

Thanks for replying and thank you very much for the info, I think I'll
use only "-tile-columns=".

Regards
Mustafa