브라우저에서 동영상을 캔버스 소스로 사용하는 브라우저의 기능을 테스트하는 방법은 무엇입니까

Question

휴대 기기의 canvas 요소에 대한 이미지 소스로 HTML5 video을 사용할 수 없다는 것을 알고있는 사람들이 있습니다 (동영상은 외부 플레이어가 브라우저 대신에). 그 기능 테스트가 필요합니다. 단순히 캔버스와 비디오 지원 (대부분의 모바일 기기를 모두 지원하지만,하지의 상호 작용하므로) 내가 이런 걸하고 생각하고 있었는데를 확인할 수 없기 때문에

: 아직

var feature = true; 

try { 
    var v = document.createElement('video'); 
    var c = document.createElement('canvas'); 
    c.getContext('2d').drawImage(v, 0, 0, 100, 100); 
} catch (e){ 
    feature = false; 
} 

alert(feature); 

를, 그것은 true를 반환합니다 iPad에서는 Android가 false을 출력합니다. 나는 아마도 이것이 iOS Safari 버그는 아니지만 내 기능 테스트의 결함이라고 가정하지만이 접근 방법에 대한 단서가 없습니다.

UPDATE : 적어도 마침내 iOS의 정확한 출력을 생성

var v = document.createElement('video'); 
var feature = false; 

if (v.canPlayType('video/mp4') == 'probably'){ 

    v.src = 'data:video/mp4;base64,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'; 

} else { 

    v.src = 'data:video/ogg;base64,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'; 

} 


var c = document.createElement('canvas'); 
c.width = c.height = 50; 
var ctx = c.getContext('2d'); 

v.play(); 

var async = setTimeout(function(){ 

    ctx.drawImage(v,0,0); 
    var data = ctx.getImageData(0, 0, 50, 50).data; 
    feature = (Math.max.apply(Math, data) > 0); 
    v.pause(); 


}, 50); 

를 아직 두 개 더 문제가 있습니다 : 나는 순간에 결국 무엇 그래서

는이 다음이다 :

• 는 complaini
• 파이어 폭스 (때로는) 실패 비동기
입니다 ng 약 SecurityError: The operation is insecure.에서 var data = ctx.getImageData(0, 0, 50, 50).data 정말 나에게 이해가 안되는 무엇.

그 아이디어가 있으십니까?

Answer 1

특정 영역에 특정 픽셀이있는 비디오를 사용할 수 있습니다 (예 : 왼쪽 상단의 검정색 픽셀). 그런 다음 비디오를 캔버스에 넣고 한 프레임 만로드하십시오. 그런 다음 getImageData을 사용하여 캔버스에서 해당 픽셀을 검색 할 수 있는지 확인하십시오.