libavcodec x264 profiles

[Spearmint]

Hi,

Im fooling around with the libavcodec api to encode a series of screenshots using the x264 encoder. Everything works fine until i tried to change the x264 profile. It is set to High 4:4:4 Predictive (at least thats what the console output tells me) by default but how do i change it?

I know there is AVCodecContext:rofile and macros like FF_PROFILE_H264_BASELINE and so on but setting the profile directly via a AVCodecContext instance just has no effect at all. Is this normal behaviour?

Edit: Another question. As i am searching for code examples using x264 and or libavcodec i encounter lines such as

ctx->partitions|=X264_PART_I8X8+X264_PART_I4X4+X264_PA RT_P8X8+X264_PART_B8X8;

or

ctx->flags2|=CODEC_FLAG2_BPYRAMID+CODEC_FLAG2_MIXED_RE FS+CODEC_FLAG2_WPRED+CODEC_FLAG2_8X8DCT+CODEC_FLAG 2_FASTPSKIP;

pretty often. Now why are people using a >Plus< (sometimes even minus) instead of an logical OR? Thats not what i understand when working with flags :P, but no one in their discussions seems to be bothered by it which bothers me.

Any suggestions?

thx

PS: Any links for good example code or even tutorials would be great too.