Change-Id: I9781a62bc1a4cd9176554d1271d87dbcafda9cb0

This commit makes zcoeff_blk cache the case where the entire block
is quantized to be zero (without applying zero-forcing) in the rate-
distortion optimization loop, and skip the forward DCT, quantization,
inverse DCT, and reconstruction process in the encode_block stage.

It now works for all the block sizes, including sub8x8 blocks.

Change-Id: I5ae60a9c436ba3637d11666733554bec4580ef98

Both decode_modes_sb and decode_modes_b had conditions to immediately
return at the beginning. Eliminating these conditions here and calling
these functions only to do a real work. Also unrolling loop for
PARTITION_SPLIT.

Change-Id: I2fc41cb74ac491f045a2f04fe68d30ff4aaa555d

fixes a crash in assembly on 32-bit linux/windows

Change-Id: I0c27e6c0ece9732b5eb2ee5b59ff42c3c8016c50

tiles are decoded in parallel within a single frame

Change-Id: I7aca87cb1c239b74eceef72bdc9f672faebac373

factorizes the code in decode_tiles(). reading the offsets backwards
wasn't doing anything to prove tile independence

Change-Id: I0395d3c77205852ebdc55efedc68291e93cef85c

Change-Id: I56f8c50ac382202f66040cd9cfaa05d889572fc7

Change-Id: Idc03f3fca4bf2d0afd33631ea1d3caf8fc34ec29

Warning was: "implicit conversion from enumeration type 'VPX_SCALING_MODE'
(aka 'enum vpx_scaling_mode_1d') to different enumeration type
'VPX_SCALING'".

Change-Id: I45689e439a8775bc1e7534d0ea1ff7c729f2c7f5

Fix warning with -Wstrict-aliasing=1

Change-Id: Idfac09be1ab328923883e63436577f1018c895b8

Fix warning with -Wstrict-aliasing=1

Change-Id: Ic37013e6477cf213925830d0bd8e6f17364ff7cc

Fix warning with -Wstrict-aliasing=1

Change-Id: Ic4e511af924247800e87d5f990636565f3dd91d2

Fix warning with -Wstrict-aliasing=1

Change-Id: I43df2781656dd7b3f4c0ec6daa283d7a78928a0c

Fix warning with -Wstrict-aliasing=1

Change-Id: Ibf4af991f2c82b8ccbdc20362da64be669564333

Wrong value was used in get_tx_type_4x4() function, so making
initialization before that call.

Change-Id: Ief30bb1e0c03b2f23d993bbf9ae18d7150ba9a83

"keyframe" variable in the current code actually means that previous
frame is a keyframe because cm->frame_type has not been initialized
in read_uncompressed_header.

Change-Id: I5645b0816c70abdef5dfc70113018d06276dac77

The clamp operation may not affect the values of the final assigned mv
where compiler may make use of strict aliasing rule to optimize out the
clamp operation. This change made the code segments to better comply
the strict aliasing rule.

Change-Id: I24502ff18bd4f9e62507a879cc8760a91a0fd07e

Added comments to make the codebase build cleanly in Doxygen.

Change-Id: I01e000ceac57dbafa04342858c8f1be250ba20d1

group error checking at the top followed by allocations, setup then
decode.

Change-Id: I877d21326bb767885520511ecea70e5fd1e28054

Change-Id: I5b17f40e515c4bcf9ebef5380270a214af4e0115