[FFmpeg-devel] [PATCH] Avoid a few shifts on each frame while decoding mpeg audio.

Michael Niedermayer michaelni
Sun Jan 16 23:12:51 CET 2011


On Sun, Jan 16, 2011 at 09:53:38PM +0100, Cl?ment B?sch wrote:
> Hi,
> 
> The MPEG audio parser seems to do a few useless shifts each time a new
> frame is sent for feeding; this patch avoids this (one read instead of 4
> shifts). I ran the fate tests locally and it seems it didn't break
> anything.
> 
> Also, I don't understand the header_count field (in use a few lines below)
> so it may be wise to check if it is not related to what I tried to
> achieve.
> 
> Regards,
> 
> -- 
> Cl?ment B.

>  mpegaudio_parser.c |    6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 813002a20dc97930cd819d7d7fca2a5a73d702ba  0001-Avoid-a-few-shifts-on-each-frame-while-decoding-mpeg.patch
> From beb7d21224596d98dd3eebca5fef43c74da5c1ad Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Cl=C3=A9ment=20B=C5=93sch?= <ubitux at gmail.com>
> Date: Sun, 16 Jan 2011 21:43:16 +0100
> Subject: [PATCH] Avoid a few shifts on each frame while decoding mpeg audio.

this looks buggy
it skips the first 3 checks and i dont see why they cant be true


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Incandescent light bulbs waste a lot of energy as heat so the EU forbids them.
Their replacement, compact fluorescent lamps, much more expensive, dont fit in
many old lamps, flicker, contain toxic mercury, produce a fraction of the light
that is claimed and in a unnatural spectrum rendering colors different than
in natural light. Ah and we now need to turn the heaters up more in winter to
compensate the lower wasted heat. Who wins? Not the environment, thats for sure
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