修复sdp解析错误

src/main/java/com/genersoft/iot/vmp/gb28181/utils/SipUtils.java

@@ -207,22 +207,18 @@ public class SipUtils {
         if (mediaDescriptionIndex == 0 && ssrcIndex == 0) {
             sdp = SdpFactory.getInstance().createSessionDescription(sdpStr);
         }else {
-            int baseSdpIndex = Math.min(mediaDescriptionIndex, ssrcIndex);
-            //ssrc规定长度为10字节，不取余下长度以避免后续还有“f=”字段
-            String substring = sdpStr.substring(0, baseSdpIndex);
-            sdp = SdpFactory.getInstance().createSessionDescription(substring);
-
             String lines[] = sdpStr.split("\\r?\\n");
+            StringBuilder sdpBuffer = new StringBuilder();
             for (String line : lines) {
                 if (line.trim().startsWith("y=")) {
                     ssrc = line.substring(2);
                 }else if (line.trim().startsWith("f=")) {
                     mediaDescription = line.substring(2);
-                }
-                if (ssrc != null && mediaDescription != null) {
-                    break;
+                }else {
+                    sdpBuffer.append(line.trim()).append("\r\n");
                 }
             }
+            sdp = SdpFactory.getInstance().createSessionDescription(sdpBuffer.toString());
         }
         return Gb28181Sdp.getInstance(sdp, ssrc, mediaDescription);
     }