LOS ANGELES — “The King’s Speech” has been crowned best picture at an Academy Awards ceremony as precise as a state coronation, the monarchy drama leading as expected with four Oscars and predictable favorites claiming acting honors. Colin Firth as stammering British ruler George VI in “The King’s Speech” earned the best-actor prize Sunday, while Natalie Portman won best actress as a delusional ballerina in “Black Swan.” The boxing drama “The Fighter” claimed both supporting-acting honors, for Christian Bale as a boxer-turned-drug-abuser and Melissa Leo as a boxing clan’s domineering matriarch. “The King’s Speech” also won the directing prize for Tom Hooper and the original-screenplay Oscar for David Seidler, a boyhood stutterer himself who was inspired by the British ruler’s struggle to overcome his own stammer. Christian Bale and Melissa Leo earned supporting-acting honors for the boxing tale “The Fighter.” Portman won out over a field that included Annette Bening for “The Kids Are All Right,” who has lost on all four of her Oscar nominations.