Altref reference frames.
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vijay
Apr 12, 2012, 8:35:11 AM4/12/12
to WebM Discussion
Hello experts,
As I read about altref frames they mayn't be used for display. Aren't
we wasting bandwidth by sending them. Equivalent bits can be
distributed to shown frame and PSNR can be increased.
What is the recommended frequency of sending altref? Is reference
encoder is generating altref frames?
Thanks in advance,
Vijay.
As I read about altref frames they mayn't be used for display. Aren't
we wasting bandwidth by sending them. Equivalent bits can be
distributed to shown frame and PSNR can be increased.
What is the recommended frequency of sending altref? Is reference
encoder is generating altref frames?
Thanks in advance,
Vijay.
Rajesh Pamula
Apr 12, 2012, 8:44:03 AM4/12/12
to webm-d...@webmproject.org
Dear Vijay,
The question of whether or not one is wasting bandwidth is based on how the alt-ref frame is generated and used for prediction of other frames. It is possible to increase bitrate if one inserts a alt-frame with not much information and which no other frame refers to. But in general a judicious use of alt-ref frame is intended to reduce the bitrate.
Recommended frequency - Depends on application, complexity and the content. And I think ref encoder can generate alt-ref frames.
Best regards,
rajesh
--
Rajesh Pamula
Post Graduate Student
Analogue and Digital Integrated Circuit Design
Imperial College London.
Residence Phone: +44-20-78522056
The question of whether or not one is wasting bandwidth is based on how the alt-ref frame is generated and used for prediction of other frames. It is possible to increase bitrate if one inserts a alt-frame with not much information and which no other frame refers to. But in general a judicious use of alt-ref frame is intended to reduce the bitrate.
Recommended frequency - Depends on application, complexity and the content. And I think ref encoder can generate alt-ref frames.
Best regards,
rajesh
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Rajesh Pamula
Post Graduate Student
Analogue and Digital Integrated Circuit Design
Imperial College London.
Residence Phone: +44-20-78522056
vijay
Apr 12, 2012, 8:55:29 AM4/12/12
to WebM Discussion
Thanks Rajesh.
On Apr 12, 5:44 pm, Rajesh Pamula <rajeshpam...@gmail.com> wrote:
> Dear Vijay,
>
> The question of whether or not one is wasting bandwidth is based on how the
> alt-ref frame is generated and used for prediction of other frames. It is
> possible to increase bitrate if one inserts a alt-frame with not much
> information and which no other frame refers to. But in general a judicious
> use of alt-ref frame is intended to reduce the bitrate.
>
> Recommended frequency - Depends on application, complexity and the content.
> And I think ref encoder can generate alt-ref frames.
>
> Best regards,
>
> rajesh
>
>
>
>
>
> On Thu, Apr 12, 2012 at 2:35 PM, vijay <vkumarban...@gmail.com> wrote:
> > Hello experts,
>
> > As I read about altref frames they mayn't be used for display. Aren't
> > we wasting bandwidth by sending them. Equivalent bits can be
> > distributed to shown frame and PSNR can be increased.
>
> > What is the recommended frequency of sending altref? Is reference
> > encoder is generating altref frames?
>
> > Thanks in advance,
> > Vijay.
>
> > --
> > You received this message because you are subscribed to the Google Groups
> > "WebM Discussion" group.
> > To post to this group, send email to webm-disc...@webmproject.org.
>
> - Show quoted text -
On Apr 12, 5:44 pm, Rajesh Pamula <rajeshpam...@gmail.com> wrote:
> Dear Vijay,
>
> The question of whether or not one is wasting bandwidth is based on how the
> alt-ref frame is generated and used for prediction of other frames. It is
> possible to increase bitrate if one inserts a alt-frame with not much
> information and which no other frame refers to. But in general a judicious
> use of alt-ref frame is intended to reduce the bitrate.
>
> Recommended frequency - Depends on application, complexity and the content.
> And I think ref encoder can generate alt-ref frames.
>
> Best regards,
>
> rajesh
>
>
>
>
>
> On Thu, Apr 12, 2012 at 2:35 PM, vijay <vkumarban...@gmail.com> wrote:
> > Hello experts,
>
> > As I read about altref frames they mayn't be used for display. Aren't
> > we wasting bandwidth by sending them. Equivalent bits can be
> > distributed to shown frame and PSNR can be increased.
>
> > What is the recommended frequency of sending altref? Is reference
> > encoder is generating altref frames?
>
> > Thanks in advance,
> > Vijay.
>
> > --
> > You received this message because you are subscribed to the Google Groups
> > "WebM Discussion" group.
> > To unsubscribe from this group, send email to
> > webm-discuss+unsubscr...@webmproject.org.
> > For more options, visit this group at
> >http://groups.google.com/a/webmproject.org/group/webm-discuss/?hl=en.
>
> --
> Rajesh Pamula
> Post Graduate Student
> Analogue and Digital Integrated Circuit Design
> Imperial College London.
> Residence Phone: +44-20-78522056- Hide quoted text -
> >http://groups.google.com/a/webmproject.org/group/webm-discuss/?hl=en.
>
> --
> Rajesh Pamula
> Post Graduate Student
> Analogue and Digital Integrated Circuit Design
> Imperial College London.
>
> - Show quoted text -
fishor
Apr 12, 2012, 11:14:06 AM4/12/12
to WebM Discussion
Are you talking about live streaming over network? I do not know if
there was some changes, but alt-ref frames are generated only on two
pass encoding.
there was some changes, but alt-ref frames are generated only on two
pass encoding.
John Koleszar
Apr 12, 2012, 12:48:37 PM4/12/12
to webm-d...@webmproject.org
Invisible frames may be generated during one pass lagged encoding in
the future, but today are only generated in two pass.
the future, but today are only generated in two pass.
> --
> You received this message because you are subscribed to the Google Groups "WebM Discussion" group.
> To post to this group, send email to webm-d...@webmproject.org.
> To unsubscribe from this group, send email to webm-discuss...@webmproject.org.
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