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1 /* ------------------------------------------------------------------
2  * Copyright (C) 1998-2009 PacketVideo
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
13  * express or implied.
14  * See the License for the specific language governing permissions
15  * and limitations under the License.
16  * -------------------------------------------------------------------
17  */
18 #include "media_clock_converter.h"
19 
20 // Use default DLL entry point for Symbian
21 #include "oscl_dll.h"
OSCL_DLL_ENTRY_POINT_DEFAULT()22 OSCL_DLL_ENTRY_POINT_DEFAULT()
23 
24 // All the rounding in this utility is using method rounding up
25 // For example, normal calculation
26 //   A / B
27 // is replaced as
28 //   (A + (B - 1))/ B
29 // In an average roudning up is same as rounding down, but it resolve some issue
30 
31 //////////////////////////////////////////////////////////////////////////////////
32 OSCL_EXPORT_REF void MediaClockConverter::set_value(const MediaClockConverter& src)
33 {
34     // Timescale value cannot be zero
35     OSCL_ASSERT(src.get_timescale() != 0);
36     if (src.get_timescale() == 0)
37     {
38         OSCL_LEAVE(OsclErrCorrupt);
39     }
40 
41     OSCL_ASSERT(timescale != 0);
42     if (0 == timescale)
43     {
44         OSCL_LEAVE(OsclErrCorrupt);
45     }
46 
47     uint64 value = (uint64(src.get_wrap_count())) << 32;
48 
49     value += src.get_current_timestamp();
50 
51     // rounding up
52     value = (uint64(value) * timescale + uint64(src.get_timescale() - 1)) / src.get_timescale();
53 
54     wrap_count = ((uint32)(value >> 32)) % timescale;
55 
56     current_ts = (uint32)(value & 0xFFFFFFFF);
57 }
58 
59 //////////////////////////////////////////////////////////////////////////////////
set_timescale(uint32 new_timescale)60 OSCL_EXPORT_REF void MediaClockConverter::set_timescale(uint32 new_timescale)
61 {
62     // Timescale value cannot be zero
63     OSCL_ASSERT(new_timescale != 0);
64     if (0 == new_timescale)
65     {
66         OSCL_LEAVE(OsclErrArgument);
67     }
68 
69     OSCL_ASSERT(timescale != 0);
70     if (0 == timescale)
71     {
72         OSCL_LEAVE(OsclErrCorrupt);
73     }
74 
75     uint64 value = ((uint64)wrap_count) << 32;
76     value += current_ts;
77 
78     // rounding up
79     value = (value * new_timescale + uint64(timescale - 1)) / timescale;
80 
81     timescale = new_timescale;
82 
83     wrap_count = ((uint32)(value >> 32)) % timescale;
84 
85     current_ts = (uint32)(value & 0xFFFFFFFF);
86 }
87 
88 //////////////////////////////////////////////////////////////////////////////////
set_clock_other_timescale(uint32 value,uint32 in_timescale)89 OSCL_EXPORT_REF void MediaClockConverter::set_clock_other_timescale(uint32 value,
90         uint32 in_timescale)
91 {
92     // Timescale value cannot be zero
93     OSCL_ASSERT(in_timescale != 0);
94     if (0 == in_timescale)
95     {
96         OSCL_LEAVE(OsclErrArgument);
97     }
98 
99     OSCL_ASSERT(timescale != 0);
100     if (0 == timescale)
101     {
102         OSCL_LEAVE(OsclErrCorrupt);
103     }
104 
105     uint64 new_value = (uint64)value * timescale;
106     uint64 in_timescale64Comp = (uint64)(in_timescale - 1);
107 
108     // rounding up
109     new_value = new_value + in_timescale64Comp ;
110     new_value /= in_timescale;
111 
112     wrap_count = ((uint32)(new_value >> 32)) % timescale;
113 
114     current_ts = (uint32)(new_value & 0xFFFFFFFF);
115 }
116 
117 //////////////////////////////////////////////////////////////////////////////////
get_timediff_and_update_clock(uint32 value,uint32 in_timescale,uint32 output_timescale)118 OSCL_EXPORT_REF uint32 MediaClockConverter::get_timediff_and_update_clock(uint32 value,
119         uint32 in_timescale,
120         uint32 output_timescale)
121 {
122     // Timescale value cannot be zero
123     OSCL_ASSERT(in_timescale != 0);
124     if (0 == in_timescale)
125     {
126         OSCL_LEAVE(OsclErrArgument);
127     }
128 
129     // convert to native timescale
130     // rounding up
131     uint64 new_value = (uint64)value * timescale + uint64(in_timescale - 1);
132     new_value /= in_timescale;
133 
134     uint32 new_timevalue = ((uint32)(new_value & 0xFFFFFFFF));
135 
136     return get_timediff_and_update_clock(new_timevalue, output_timescale);
137 
138 }
139 
140 //////////////////////////////////////////////////////////////////////////////////
get_timediff_and_update_clock(uint32 value,uint32 output_timescale)141 OSCL_EXPORT_REF uint32 MediaClockConverter::get_timediff_and_update_clock(uint32 value,
142         uint32 output_timescale)
143 {
144     // Timescale value cannot be zero
145     OSCL_ASSERT(timescale != 0);
146     if (0 == timescale)
147     {
148         OSCL_LEAVE(OsclErrCorrupt);
149     }
150 
151     uint32 diff = value - current_ts;
152 
153     // convert to output timescale
154     // rounding up
155     uint64 new_value = (uint64)diff * output_timescale + uint64(timescale - 1);
156     new_value /= timescale;
157 
158     diff = ((uint32)(new_value & 0xFFFFFFFF));
159 
160     if (update_clock(value))
161     {
162         return diff;
163     }
164 
165     return 0;
166 }
167 
168 
169 //////////////////////////////////////////////////////////////////////////////////
update_clock(uint32 new_ts)170 OSCL_EXPORT_REF bool MediaClockConverter::update_clock(uint32 new_ts)
171 {
172     uint32 diff = new_ts - current_ts;
173     if (new_ts < current_ts)
174     {
175         if (diff < WRAP_THRESHOLD)
176         {
177             if (++wrap_count >= timescale)
178             {
179                 wrap_count = 0;
180             }
181             current_ts = new_ts;
182             return true;
183         }
184         // otherwise this an earlier value so ignore it.
185     }
186     else
187     {
188         if (diff < MISORDER_THRESHOLD)
189         {
190             current_ts = new_ts;
191             return true;
192         }
193         // otherwise this an earlier value so ignore it.
194     }
195     return false;
196 }
197 
198 //////////////////////////////////////////////////////////////////////////////////
get_converted_ts(uint32 new_timescale) const199 OSCL_EXPORT_REF uint32 MediaClockConverter::get_converted_ts(uint32 new_timescale) const
200 {
201     // Timescale value cannot be zero
202     OSCL_ASSERT(timescale != 0);
203     if (0 == timescale)
204     {
205         OSCL_LEAVE(OsclErrCorrupt);
206     }
207 
208     uint64 value = ((uint64)wrap_count) << 32;
209     // rounding up
210     value = ((value + uint64(current_ts)) * uint64(new_timescale) + uint64(timescale - 1)) / uint64(timescale);
211 
212     return ((uint32) value);
213 
214 }
215