actionscript 截图功能实现
由于截图访问的是 外部 rtmp直播流 所以调用BitmapData.draw时 控制台报以下错误：
SecurityError: Error #2123: 安全沙箱冲突:BitmapData.draw: XXX 不能访问 rtmp://XXXXX。未被授权访问任何策略文件。
解决方法是：
我们的视频服务器是用Crtmpserver，网上的解决办法大多是FMS的 ；
在转码服务器 的 BaseOutNetRTMPStream::SignalAttachedToInStream() 方法中添加以下 + 号的代码：
in void BaseOutNetRTMPStream::SignalAttachedToInStream(), I added the
following code after stream begin to allow Video samples:
+ //XXX. notify |RtmpSampleAccess
+ /*
+ message = StreamMessageFactory::GetNotifyRtmpSampleAccess(
+ _pChannelVideo->id, _rtmpStreamId, absoluteTimestamp, false, true,
true);
+ TRACK_MESSAGE("Message:\n%s", STR(message.ToString()));
+ if (!_pRTMPProtocol->SendMessage(message)) {
+ FATAL("Unable to send message");
+ _pRTMPProtocol->EnqueueForDelete();
+ return false;
+ }
+ */
+
修改以下代码:
//10. notify |RtmpSampleAccess
message = StreamMessageFactory::GetNotifyRtmpSampleAccess(
_pChannelAudio->id, _rtmpStreamId, 0, true, true, true);
TRACK_MESSAGE("Message:\n%s", STR(message.ToString()));
if (!_pRTMPProtocol->SendMessage(message)) {
FATAL("Unable to send message");
_pRTMPProtocol->EnqueueForDelete();
return;
}
在actionscript中的 截图实现过程为：
var imager:BitmapData = new BitmapData(mvideo.width,mvideo.height); ExternalInterface.call("errorFun","1"); imager.draw(mvideo.video); var bs:ByteArray = new ByteArray(); imager.encode(new Rectangle(0,0,mvideo.width,mvideo.height), new flash.display.JPEGEncoderOptions(), bs); var base64Code:String = Base64.encode(bs); ExternalInterface.call("setImage",base64Code);
Base64的源码为：
/* Base64 library for ActionScript 3.0. * * Copyright (C) 2007 Ma Bingyao <andot@ujn.edu.cn> * Version: 1.1 * LastModified: Oct 26, 2007 * This library is free. You can redistribute it and/or modify it. */ /* * interfaces: * import org.phprpc.util.Base64; * import flash.utils.ByteArray; * var data:ByteArray = new ByteArray(); * data.writeUTFBytes("Hello PHPRPC"); * var b64:String = Base64.encode(data); * trace(b64); * trace(Base64.decode(b64)); */ package com.zonekey.player{ import flash.utils.ByteArray; public class Base64 { private static const encodeChars:Array = ['A','B','C','D','E','F','G','H', 'I','J','K','L','M','N','O','P', 'Q','R','S','T','U','V','W','X', 'Y','Z','a','b','c','d','e','f', 'g','h','i','j','k','l','m','n', 'o','p','q','r','s','t','u','v', 'w','x','y','z','0','1','2','3', '4','5','6','7','8','9','+','/']; private static const decodeChars:Array = [-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1]; public static function encode(data:ByteArray):String { var out:Array = []; var i:int = 0; var j:int = 0; var r:int = data.length % 3; var len:int = data.length-r; var c:int; while (i < len) { c = data[i++] << 16 | data[i++] << 8 | data[i++]; out[j++] = encodeChars[c >> 18] + encodeChars[c >> 12 & 0x3f] + encodeChars[c >> 6 & 0x3f] + encodeChars[c & 0x3f]; } if (r == 1) { c = data[i++]; out[j++] = encodeChars[c >> 2] + encodeChars[(c & 0x03) << 4] + "=="; } else if (r == 2) { c = data[i++] << 8 | data[i++]; out[j++] = encodeChars[c >> 10] + encodeChars[c >> 4 & 0x3f] + encodeChars[(c & 0x0f) << 2] + "="; } return out.join(''); } public static function decode(str:String):ByteArray { var c1:int; var c2:int; var c3:int; var c4:int; var i:int; var len:int; var out:ByteArray; len = str.length; i = 0; out = new ByteArray(); while (i < len) { do { c1 = decodeChars[str.charCodeAt(i++) & 0xff]; } while (i < len && c1 == -1); if (c1 == -1) { break; } // c2 do { c2 = decodeChars[str.charCodeAt(i++) & 0xff]; } while (i < len && c2 == -1); if (c2 == -1) { break; } out.writeByte((c1 << 2) | ((c2 & 0x30) >> 4)); // c3 do { c3 = str.charCodeAt(i++) & 0xff; if (c3 == 61) { return out; } c3 = decodeChars[c3]; } while (i < len && c3 == -1); if (c3 == -1) { break; } out.writeByte(((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2)); // c4 do { c4 = str.charCodeAt(i++) & 0xff; if (c4 == 61) { return out; } c4 = decodeChars[c4]; } while (i < len && c4 == -1); if (c4 == -1) { break; } out.writeByte(((c3 & 0x03) << 6) | c4); } return out; } } }
至此，actionscript的截图并将图片的base64码传递给javascript的功能 就实现了。
