int start_mb_y; ///< start mb_y of this thread (so current thread should process start_mb_y <= row < end_mb_y)
int end_mb_y; ///< end mb_y of this thread (so current thread should process start_mb_y <= row < end_mb_y)
struct MpegEncContext *thread_context[MAX_THREADS];
+ int slice_context_count; ///< number of used thread_contexts
/**
* copy of the previous picture structure.