diff --git a/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.h b/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.h
index 1c0297aebcac059a383df740d0e4b70b5430d9bf..10596b41df93618b0f793733437878981be00eb2 100644
--- a/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.h
+++ b/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.h
@@ -32,7 +32,8 @@
 #include "ff_ffplay.h"
 
 
-#define MAX_PKT_QUEUE_DEEP 350
+#define MAX_PKT_QUEUE_DEEP   350
+#define MAX_DECODING_SAMPLES 16
 
 typedef struct VTBPicture {
     double              pts;
@@ -44,6 +45,13 @@ typedef struct VTBPicture {
 } VTBPicture;
 
 
+typedef struct sample_info {
+    double dts;
+    double pts;
+    int    serial;
+} sample_info;
+
+
 typedef struct sort_queue {
     double              dts;
     double              pts;
@@ -82,6 +90,9 @@ typedef struct VideoToolBoxContext {
     bool                        dealloced;
     int                         m_buffer_deep;
     AVPacket                    m_buffer_packet[MAX_PKT_QUEUE_DEEP];
+
+    sample_info                 sample_info_array[MAX_DECODING_SAMPLES];
+    int                         sample_info_index;
 } VideoToolBoxContext ;
 
 
diff --git a/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.m b/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.m
index 18376090ef7399fad52b2eb22b6ca737003a3791..15f2567d7976616cf4f8ddff3b1ddcd2239a4193 100644
--- a/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.m
+++ b/ios/IJKMediaPlayer/IJKMediaPlayer/ijkmedia/ijkplayer/ios/pipeline/IJKVideoToolBox.m
@@ -733,26 +733,13 @@ VideoToolBoxContext* init_videotoolbox(FFPlayer* ffp, AVCodecContext* ic)
     int codec           = ic->codec_id;
     uint8_t* extradata  = ic->extradata;
 
-    VideoToolBoxContext* context_vtb = malloc(sizeof(VideoToolBoxContext));
+    VideoToolBoxContext *context_vtb = (VideoToolBoxContext *)mallocz(sizeof(VideoToolBoxContext));
     if (!context_vtb) {
         goto failed;
     }
 
-    context_vtb->m_convert_bytestream = false;
-    context_vtb->m_convert_3byteTo4byteNALSize = false;
-    context_vtb->refresh_request = false;
-    context_vtb->new_seg_flag = false;
-    context_vtb->recovery_drop_packet = false;
-    context_vtb->refresh_session = false;
     context_vtb->idr_based_identified = true;
-    context_vtb->dealloced = false;
-    context_vtb->last_keyframe_pts = 0;
-    context_vtb->m_max_ref_frames = 0;
     context_vtb->ffp = ffp;
-    context_vtb->serial = 0;
-    context_vtb->last_sort = 0;
-    context_vtb->m_buffer_deep = 0;
-    memset(context_vtb->m_buffer_packet, 0, sizeof(context_vtb->m_buffer_packet));
 
     switch (profile) {
         case FF_PROFILE_H264_HIGH_10: