b18f8cbf3d
Revert "swscale: update context offsets after removal of AlpMmxFilter." (commit a95e3fa90b4190381b65d180eec5a4027075e2da) and Revert "swscale: Remove some write-only variables related to alpha handling." (commit 9d03cb9fc5ddf914920ab0dbe13f19a34c754966). They broke alpha handling - it's the evil inline asm that still uses that variable, so it's not truely write-only.