avresample: Introduce AVFrame-based API
tiff: Improve grayscale support

Only use PAL8 if palette is present, else use GRAY8 for pixfmt.

Instead of simulating a grayscale palette, use real grayscale pixels, if no
palette is actually defined.

Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.eu>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
lavf/img2dec: Initialize a stack variable.

Fixes a valgrind warning about using unitialised memory.
Hopefully fixes crashes on several platforms reported through fate.
Merge commit 'fb1ddcdc8f51b9d261ae8e9c26b91e81f7b6bf45'

* commit 'fb1ddcdc8f51b9d261ae8e9c26b91e81f7b6bf45':
  avresample: Introduce AVFrame-based API

Conflicts:
	libavresample/utils.c
	libavutil/version.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '2597a842a0a2c7e8aa76f32733d27bf64817ae86'

* commit '2597a842a0a2c7e8aa76f32733d27bf64817ae86':
  tiff: Improve grayscale support

Conflicts:
	libavcodec/tiff.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge remote-tracking branch 'cehoyos/master'

* cehoyos/master:
  lavf/img2dec: Initialize a stack variable.

Merged-by: Michael Niedermayer <michaelni@gmx.at>