x86: fdct: Only build fdct code if encoders have been enabled

fdct is only initialized if encoders are enabled.
mov: Don't allocate arrays with av_malloc that will be realloced

CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
ismindex: Use the individual stream duration instead of the global one

The stream duration is used for calculating the duration of the
last fragment easily without manually parsing anything else than
the mfra/tfra atoms. When the global file duration was used
previously, the duration of the last fragment could end up wrong
if the streams weren't equally long.

Signed-off-by: Martin Storsjö <martin@martin.st>
ismindex: Calculate the file duration among the included tracks

If the input file contains other tracks (non video/audio) that
aren't included in ismindex, the global file duration as returned
by libavformat might not be equal to the maximum of the duration
of the actual included tracks.

Signed-off-by: Martin Storsjö <martin@martin.st>
ismindex: Change the duration field to int64_t

This reduces the risk for overflow in pathlogical cases.

Signed-off-by: Martin Storsjö <martin@martin.st>
doxy: Document avlog

Provide some information for every function and add a group.
x86: xviddct: Employ more specific ifdefs

This avoids building mmxext and sse2 code when disabled by configure.
x86: fdct: Initialize optimized fdct implementations in the standard way
swscale: provide a default scaler if none is set

Lanczos for general case, sinc for upscaling, Gaussian for
downscaling. According to current literature these scalers
should be the best quality-wise algorithms for each case.

Inspired from a patch by wm4 <nfxjfg@googlemail.com>

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
x86: dsputil: Separate ff_add_hfyu_median_prediction_cmov from dsputil_mmx

The function does not depend on MMX and compilation without MMX enabled
fails if the function is compiled conditional on MMX availability.
oggparsevorbis: return meaningful errors

Signed-off-by: Diego Biurrun <diego@biurrun.de>
bmv: Remove unused variable
x86: fdct: Employ more specific ifdefs

This avoids building mmxext and sse2 code when disabled by configure.