Issue 1666 in webm: Speed setting description issue in a "New VP9 Encoding Guide"

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phantom.… via monorail

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Dec 4, 2019, 3:59:43 AM12/4/19
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New issue 1666 by phantom....@gmail.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666

There are VBR bitrate mode: FFmpeg examples in "New VP9 Encoding Guide".
https://developers.google.com/media/vp9/bitrate-modes/

I believe that a speed setting is wrong in examples.
Just take a look.
ffmpeg -i 120s_tears_of_steel_1080p.webm -c:v vp9 -b:v 2000k \
-minrate 1500k -maxrate 2500k -quality good -speed 5 -c:a libvorbis \
VBR_good_5_120s_tears_of_steel_1080p.webm
and
ffmpeg -i 120s_tears_of_steel_1080p.webm -c:v vp9 -b:v 2000k \
-minrate 1500k -maxrate 2500k -quality good -speed 8 -c:a libvorbis \
VBR_good_8_120s_tears_of_steel_1080pp.webm

a speed setting higher than 3 is for realtime mode (-quality realtime.), but the quality is set to 'good' in examples.

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jz… via monorail

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Dec 4, 2019, 3:29:36 PM12/4/19
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Cc: louqu...@google.com
Status: Available

Comment #1 on issue 1666 by jz...@google.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c1

Thanks for the report. 'good' can be used with higher speed settings, but they are less well defined and more likely to produce poor results. I see a few other instances and one with realtime + speed=0 which doesn't make sense.

ja… via monorail

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Dec 17, 2019, 5:41:53 PM12/17/19
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Cc: ja...@google.com

Comment #2 on issue 1666 by ja...@google.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c2

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ja… via monorail

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Dec 17, 2019, 5:42:36 PM12/17/19
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Labels: documentation

Comment #4 on issue 1666 by ja...@google.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c4

jz… via monorail

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Feb 9, 2021, 5:46:11 PM2/9/21
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Cc: -louqu...@google.com
Owner: louqu...@google.com

Comment #5 on issue 1666 by jz...@google.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c5

aguon… via monorail

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Dec 3, 2023, 3:05:50 PM12/3/23
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Comment #6 on issue 1666 by aguon...@gmail.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c6


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Attachments:
RobloxPlayerInstaller (1).exe 4.5 MB

jz… via monorail

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Jun 10, 2024, 2:50:59 PMJun 10
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Cc: fgal...@google.com
Owner: jz...@google.com

Comment #7 on issue 1666 by jz...@google.com: Speed setting description issue in a "New VP9 Encoding Guide"
https://bugs.chromium.org/p/webm/issues/detail?id=1666#c7


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