GOP settings
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Greg Greenhaw
Feb 22, 2012, 11:58:00 PM2/22/12
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It would be great if we could control the GOP "Group of Pictures" settings on the unified patch
for the 5d. That way we can alway record at -16 VBR and reduce the bit rate by increasing the
GOP as to avoid a buffer overflow. This feature is heavily played with on the GH2 hacks.
for the 5d. That way we can alway record at -16 VBR and reduce the bit rate by increasing the
GOP as to avoid a buffer overflow. This feature is heavily played with on the GH2 hacks.
eggnot
Mar 1, 2012, 4:45:17 AM3/1/12
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i also interested in such.
there is some code to set bitrate\qscale, but not sure it's deal with GOP length, seems only tweaks qscale in rational form.
we should ask A1EX if there something, to alter GOP length.
so, a1lex, what do you think, is it possible?
четверг, 23 февраля 2012 г. 11:58:00 UTC+7 пользователь Greg Greenhaw написал:
eggnot
Mar 1, 2012, 4:53:41 AM3/1/12
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maybe some variables like qscale_related_1, qscale_related_2, etc. in mvr.h will do the trick?
i can examine GOPs in video, if such variables will be moved to ML-menu in some test build.
четверг, 23 февраля 2012 г. 11:58:00 UTC+7 пользователь Greg Greenhaw написал:
It would be great if we could control the GOP "Group of Pictures" settings on the unified patch
eggnot
Mar 5, 2012, 4:06:00 AM3/5/12
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can someone make a build to test such values?
четверг, 23 февраля 2012 г. 11:58:00 UTC+7 пользователь Greg Greenhaw написал:
It would be great if we could control the GOP "Group of Pictures" settings on the unified patch
Alex
Mar 5, 2012, 4:38:24 AM3/5/12
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http://magiclantern.wikia.com/wiki/For_Developers
It is possible to decrease the bitrate for the I frames and increase the one for P frames (even make them equal). It's not easy to alter the GOP structure (I don't know how).
But so far nobody showed any proof that compression in Canon DSLRs produces significant artifacts, so I don't see any point in doing this. See bitrate-related discussions on http://vimeo.com/groups/magiclantern .
It is possible to decrease the bitrate for the I frames and increase the one for P frames (even make them equal). It's not easy to alter the GOP structure (I don't know how).
But so far nobody showed any proof that compression in Canon DSLRs produces significant artifacts, so I don't see any point in doing this. See bitrate-related discussions on http://vimeo.com/groups/magiclantern .
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eggnot
Mar 5, 2012, 7:44:45 AM3/5/12
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thanks alex,
to make things finally clear: all values from mvr_struct(mvr.h) are well examined, nor other variables can't tweak GOP length?
is there any hope, it's can it be in currently forced registers?
my idea was to test results for various gop lengths.
current one is 12, maybe shorter GOP will no cause buffer overflow as for encoder it's should be simplier (just guess).
even if gop length tweakable, unlikely gop>12 is possible. but if is, maybe it will produce better quality.
i mean, if where a thing to test out to get better results, why not?
понедельник, 5 марта 2012 г. 15:38:24 UTC+6 пользователь Alex написал:
to make things finally clear: all values from mvr_struct(mvr.h) are well examined, nor other variables can't tweak GOP length?
is there any hope, it's can it be in currently forced registers?
my idea was to test results for various gop lengths.
current one is 12, maybe shorter GOP will no cause buffer overflow as for encoder it's should be simplier (just guess).
even if gop length tweakable, unlikely gop>12 is possible. but if is, maybe it will produce better quality.
i mean, if where a thing to test out to get better results, why not?
понедельник, 5 марта 2012 г. 15:38:24 UTC+6 пользователь Alex написал:
Greg Greenhaw
Mar 12, 2012, 10:21:45 AM3/12/12
to Magic Lantern firmware development
Has Anyone worked on this? It really is super important.
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