diff --git a/minimp4.h b/minimp4.h
index 1fc01d2..0c009fc 100644
--- a/minimp4.h
+++ b/minimp4.h
@@ -331,7 +331,7 @@ typedef struct
 } mp4_h26x_writer_t;
 
 int mp4_h26x_write_init(mp4_h26x_writer_t *h, MP4E_mux_t *mux, int width, int height, int is_hevc);
-int mp4_h26x_write_close(mp4_h26x_writer_t *h);
+void mp4_h26x_write_close(mp4_h26x_writer_t *h);
 int mp4_h26x_write_nal(mp4_h26x_writer_t *h, const unsigned char *nal, int length, unsigned timeStamp90kHz_next);
 
 /************************************************************************/
@@ -2198,7 +2198,7 @@ int mp4_h26x_write_init(mp4_h26x_writer_t *h, MP4E_mux_t *mux, int width, int he
     return MP4E_STATUS_OK;
 }
 
-int mp4_h26x_write_close(mp4_h26x_writer_t *h)
+void mp4_h26x_write_close(mp4_h26x_writer_t *h)
 {
 #if MINIMP4_TRANSCODE_SPS_ID
     h264_sps_id_patcher_t *p = &h->sps_patcher;
diff --git a/minimp4_test.c b/minimp4_test.c
index b7c4b01..f9629a1 100644
--- a/minimp4_test.c
+++ b/minimp4_test.c
@@ -107,15 +107,28 @@ int demux(uint8_t *input_buf, ssize_t input_size, FILE *fout)
             unsigned frame_bytes, timestamp, duration;
             MP4D_file_offset_t ofs = MP4D_frame_offset(&mp4, ntrack, i, &frame_bytes, &timestamp, &duration);
             uint8_t *mem = input_buf + ofs;
-            mem[0] = 0; mem[1] = 0; mem[2] = 0; mem[3] = 1;
             sum_duration += duration;
-            fwrite(mem + USE_SHORT_SYNC, 1, frame_bytes - USE_SHORT_SYNC, fout);
+            while (frame_bytes)
+            {
+                uint32_t size = ((uint32_t)mem[0] << 24) | ((uint32_t)mem[1] << 16) | ((uint32_t)mem[2] << 8) | mem[3];
+                size += 4;
+                mem[0] = 0; mem[1] = 0; mem[2] = 0; mem[3] = 1;
+                fwrite(mem + USE_SHORT_SYNC, 1, size - USE_SHORT_SYNC, fout);
+                if (frame_bytes < size)
+                {
+                    printf("error: demux sample failed\n");
+                    exit(1);
+                }
+                frame_bytes -= size;
+                mem += size;
+            }
         }
     }
 
     MP4D_close(&mp4);
     if (input_buf)
         free(input_buf);
+    return 0;
 }
 
 int main(int argc, char **argv)
diff --git a/scripts/test.sh b/scripts/test.sh
index 2f0d9c6..5fe9695 100755
--- a/scripts/test.sh
+++ b/scripts/test.sh
@@ -4,7 +4,11 @@ CUR_DIR=$(cd $(dirname ${CUR_DIR}); pwd)/$(basename ${CUR_DIR})/
 
 pushd $CUR_DIR/..
 
-./minimp4_x86 vectors/foreman.264 out.mp4
+test_executable() {
+
+EXEC=$1
+
+$EXEC vectors/foreman.264 out.mp4
 if ! cmp ./out.mp4 vectors/out_ref.mp4 >/dev/null 2>&1
 then
     echo test failed
@@ -12,7 +16,7 @@ then
 fi
 rm out.mp4
 
-./minimp4_x86 -s vectors/foreman.264 out.mp4
+$EXEC -s vectors/foreman.264 out.mp4
 if ! cmp ./out.mp4 vectors/out_sequential_ref.mp4 >/dev/null 2>&1
 then
     echo sequential test failed
@@ -20,7 +24,7 @@ then
 fi
 rm out.mp4
 
-./minimp4_x86 -f vectors/foreman.264 out.mp4
+$EXEC -f vectors/foreman.264 out.mp4
 if ! cmp ./out.mp4 vectors/out_fragmentation_ref.mp4 >/dev/null 2>&1
 then
     echo fragmentation test failed
@@ -28,7 +32,7 @@ then
 fi
 rm out.mp4
 
-./minimp4_x86 vectors/foreman_slices.264 out.mp4
+$EXEC vectors/foreman_slices.264 out.mp4
 if ! cmp ./out.mp4 vectors/out_slices_ref.mp4 >/dev/null 2>&1
 then
     echo slices test failed
@@ -36,36 +40,33 @@ then
 fi
 rm out.mp4
 
-qemu-arm ./minimp4_arm_gcc vectors/foreman.264 out.mp4
-if ! cmp ./out.mp4 vectors/out_ref.mp4 >/dev/null 2>&1
+$EXEC -d vectors/out_ref.mp4 out.h264
+if ! cmp ./out.h264 vectors/foreman.264 >/dev/null 2>&1
 then
-    echo test failed
+    echo demux test failed
     exit 1
 fi
-rm out.mp4
+rm out.h264
 
-qemu-arm ./minimp4_arm_gcc -s vectors/foreman.264 out.mp4
-if ! cmp ./out.mp4 vectors/out_sequential_ref.mp4 >/dev/null 2>&1
+$EXEC -d vectors/out_sequential_ref.mp4 out.h264
+if ! cmp ./out.h264 vectors/foreman.264 >/dev/null 2>&1
 then
-    echo sequential test failed
+    echo demux sequential test failed
     exit 1
 fi
-rm out.mp4
+rm out.h264
 
-qemu-arm ./minimp4_arm_gcc -f vectors/foreman.264 out.mp4
-if ! cmp ./out.mp4 vectors/out_fragmentation_ref.mp4 >/dev/null 2>&1
+$EXEC -d vectors/out_slices_ref.mp4 out.h264
+if ! cmp ./out.h264 vectors/foreman_slices.264 >/dev/null 2>&1
 then
-    echo fragmentation test failed
+    echo demux slices test failed
     exit 1
 fi
-rm out.mp4
+rm out.h264
 
-qemu-arm ./minimp4_arm_gcc vectors/foreman_slices.264 out.mp4
-if ! cmp ./out.mp4 vectors/out_slices_ref.mp4 >/dev/null 2>&1
-then
-    echo slices test failed
-    exit 1
-fi
-rm out.mp4
+}
+
+test_executable ./minimp4_x86
+test_executable "qemu-arm ./minimp4_arm_gcc"
 
 echo test passed
diff --git a/vectors/foreman.264 b/vectors/foreman.264
index c17064c..28927b2 100644
Binary files a/vectors/foreman.264 and b/vectors/foreman.264 differ
diff --git a/vectors/foreman_slices.264 b/vectors/foreman_slices.264
index 6d6cb73..88e8896 100644
Binary files a/vectors/foreman_slices.264 and b/vectors/foreman_slices.264 differ