[FFmpeg-devel] [PATCH 2/3] base64: optimize av_base64_encode()

[Michael Niedermayer]

On Fri, Jan 20, 2012 at 11:32:46PM +0100, Reimar Döffinger wrote:
> On Fri, Jan 20, 2012 at 10:57:19PM +0100, Michael Niedermayer wrote:
> > This makes the code 2-3 times as fast
> > 
> > Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> > ---
> >  libavutil/base64.c |   10 ++++++++++
> >  1 files changed, 10 insertions(+), 0 deletions(-)
> > 
> > diff --git a/libavutil/base64.c b/libavutil/base64.c
> > index a791a8e..80ab44b 100644
> > --- a/libavutil/base64.c
> > +++ b/libavutil/base64.c
> > @@ -26,6 +26,7 @@
> >  
> >  #include "common.h"
> >  #include "base64.h"
> > +#include "intreadwrite.h"
> >  
> >  /* ---------------- private code */
> >  static const uint8_t map2[] =
> > @@ -82,6 +83,15 @@ char *av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)
> >          out_size < AV_BASE64_SIZE(in_size))
> >          return NULL;
> >      ret = dst = out;
> > +    while (bytes_remaining > 3) {
> > +        i_bits = AV_RB32(in);
> > +        in += 3; bytes_remaining -= 3;
> > +        *dst++ = b64[ i_bits>>26        ];
> > +        *dst++ = b64[(i_bits>>20) & 0x3F];
> > +        *dst++ = b64[(i_bits>>14) & 0x3F];
> > +        *dst++ = b64[(i_bits>>8 ) & 0x3F];
> > +    }
> 
> Looks fine to me, though I am not sure if it is a bit unfortunate
> we are not requiring alignment on the buffers...

applied, thanks

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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