iphone - How to fix video orientation issue in iOS -

i working app in user picks video photos , uploads server. server .net server , video gets rotated. know reason of problem same in case of image (you may refer earlier answer https://stackoverflow.com/a/10601175/1030951 ) , googled , got code fix video orientation , got code raywenderlich.com , modified in following way. output video works fine video mute. plays doesn't play audio. kindly me if missing something.

i pass info dictionary of -(void)imagepickercontroller:(uiimagepickercontroller *)picker didfinishpickingmediawithinfo:(nsdictionary *)info method

- (void)fix:(nsdictionary*)pobjinfodirectory withfilename:(nsstring*)pstroutputfilename {     firstasset = [avasset assetwithurl:[pobjinfodirectory objectforkey:uiimagepickercontrollermediaurl]];       if(firstasset !=nil)     {         //create avmutablecomposition object.this object hold our multiple avmutablecompositiontrack.         avmutablecomposition* mixcomposition = [[avmutablecomposition alloc] init];          //video track         avmutablecompositiontrack *firsttrack = [mixcomposition addmutabletrackwithmediatype:avmediatypevideo preferredtrackid:kcmpersistenttrackid_invalid];         [firsttrack inserttimerange:cmtimerangemake(kcmtimezero, firstasset.duration) oftrack:[[firstasset trackswithmediatype:avmediatypevideo] objectatindex:0] attime:kcmtimezero error:nil];          avmutablevideocompositioninstruction * maininstruction = [avmutablevideocompositioninstruction videocompositioninstruction];                  maininstruction.timerange = cmtimerangemake(kcmtimezero, firstasset.duration);          //fixing orientation//         avmutablevideocompositionlayerinstruction *firstlayerinstruction = [avmutablevideocompositionlayerinstruction videocompositionlayerinstructionwithassettrack:firsttrack];          avassettrack *firstassettrack = [[firstasset trackswithmediatype:avmediatypevideo] objectatindex:0];          uiimageorientation firstassetorientation_  = uiimageorientationup;          bool  isfirstassetportrait_  = no;          cgaffinetransform firsttransform = firstassettrack.preferredtransform;          if(firsttransform.a == 0 && firsttransform.b == 1.0 && firsttransform.c == -1.0 && firsttransform.d == 0)         {             firstassetorientation_= uiimageorientationright; isfirstassetportrait_ = yes;         }                 if(firsttransform.a == 0 && firsttransform.b == -1.0 && firsttransform.c == 1.0 && firsttransform.d == 0)         {             firstassetorientation_ =  uiimageorientationleft; isfirstassetportrait_ = yes;         }         if(firsttransform.a == 1.0 && firsttransform.b == 0 && firsttransform.c == 0 && firsttransform.d == 1.0)         {             firstassetorientation_ =  uiimageorientationup;         }         if(firsttransform.a == -1.0 && firsttransform.b == 0 && firsttransform.c == 0 && firsttransform.d == -1.0)         {             firstassetorientation_ = uiimageorientationdown;         }          cgfloat firstassetscaletofitratio = 320.0/firstassettrack.naturalsize.width;          if(isfirstassetportrait_)         {             firstassetscaletofitratio = 320.0/firstassettrack.naturalsize.height;             cgaffinetransform firstassetscalefactor = cgaffinetransformmakescale(firstassetscaletofitratio,firstassetscaletofitratio);             [firstlayerinstruction settransform:cgaffinetransformconcat(firstassettrack.preferredtransform, firstassetscalefactor) attime:kcmtimezero];         }         else         {             cgaffinetransform firstassetscalefactor = cgaffinetransformmakescale(firstassetscaletofitratio,firstassetscaletofitratio);             [firstlayerinstruction settransform:cgaffinetransformconcat(cgaffinetransformconcat(firstassettrack.preferredtransform, firstassetscalefactor),cgaffinetransformmaketranslation(0, 160)) attime:kcmtimezero];         }         [firstlayerinstruction setopacity:0.0 attime:firstasset.duration];          maininstruction.layerinstructions = [nsarray arraywithobjects:firstlayerinstruction,nil];;          avmutablevideocomposition *maincompositioninst = [avmutablevideocomposition videocomposition];         maincompositioninst.instructions = [nsarray arraywithobject:maininstruction];         maincompositioninst.frameduration = cmtimemake(1, 30);         maincompositioninst.rendersize = cgsizemake(320.0, 480.0);          nsarray *paths = nssearchpathfordirectoriesindomains(nsdocumentdirectory, nsuserdomainmask, yes);         nsstring *documentsdirectory = [paths objectatindex:0];         nsstring *mypathdocs =  [documentsdirectory stringbyappendingpathcomponent:[nsstring stringwithformat:@"mergevideo-%d.mov",arc4random() % 1000]];          nsurl *url = [nsurl fileurlwithpath:mypathdocs];          avassetexportsession *exporter = [[avassetexportsession alloc] initwithasset:mixcomposition presetname:avassetexportpresethighestquality];          exporter.outputurl=url;         exporter.outputfiletype = avfiletypequicktimemovie;         exporter.videocomposition = maincompositioninst;         exporter.shouldoptimizefornetworkuse = yes;         [exporter exportasynchronouslywithcompletionhandler:^          {              dispatch_async(dispatch_get_main_queue(), ^{                  [self exportdidfinish:exporter];              });          }];     } }  - (void)exportdidfinish:(avassetexportsession*)session {     if(session.status == avassetexportsessionstatuscompleted)     {         nsurl *outputurl = session.outputurl;         alassetslibrary *library = [[alassetslibrary alloc] init];          if ([library videoatpathiscompatiblewithsavedphotosalbum:outputurl])         {             if ([self.delegate respondstoselector:@selector(videoexported)])                 [self.delegate videoexported];             }     }            firstasset = nil; } 

add after //video track part

        //audio track         avmutablecompositiontrack *firstaudiotrack = [mixcomposition addmutabletrackwithmediatype:avmediatypeaudio preferredtrackid:kcmpersistenttrackid_invalid];         [firstaudiotrack inserttimerange:cmtimerangemake(kcmtimezero, firstasset.duration) oftrack:[[firstasset trackswithmediatype:avmediatypeaudio] objectatindex:0] attime:kcmtimezero error:nil];