pvmp3_reorder.cpp revision f4ea1f92bc56a8ffceddba0dbd3979fe0219b13c 
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/*
19------------------------------------------------------------------------------
20
21   PacketVideo Corp.
22   MP3 Decoder Library
23
24   Filename: pvmp3_reorder.cpp
25
26
27     Date: 09/21/2007
28
29------------------------------------------------------------------------------
30 REVISION HISTORY
31
32
33 Description:
34
35------------------------------------------------------------------------------
36 INPUT AND OUTPUT DEFINITIONS
37
38 Inputs:
39
40    int32 xr[ ],                rescaled data
41    struct gr_info_s *gr_info,  granule structure
42    mp3Header *info,            mp3 header info
43    int32  Scratch_mem[198]     for temporary usage
44
45 Outputs:
46
47    int32 xr[ ],                reordered data
48
49------------------------------------------------------------------------------
50 FUNCTION DESCRIPTION
51
52 If short blocks are used (block_type[gr][ch]=='10'), the rescaled data
53 xr[scf_band][window][freq_line] shall be reordered in polyphase subband
54 order, xr[subband][window][freq_line], prior to the IMDCT operation.
55
56------------------------------------------------------------------------------
57 REQUIREMENTS
58
59
60------------------------------------------------------------------------------
61 REFERENCES
62 [1] ISO MPEG Audio Subgroup Software Simulation Group (1996)
63     ISO 13818-3 MPEG-2 Audio Decoder - Lower Sampling Frequency Extension
64
65
66------------------------------------------------------------------------------
67 PSEUDO-CODE
68
69------------------------------------------------------------------------------
70*/
71
72
73/*----------------------------------------------------------------------------
74; INCLUDES
75----------------------------------------------------------------------------*/
76#include "pv_mp3dec_fxd_op.h"
77#include "pvmp3_dec_defs.h"
78#include "pvmp3_reorder.h"
79#include "pvmp3_tables.h"
80#include "mp3_mem_funcs.h"
81
82/*----------------------------------------------------------------------------
83; MACROS
84; Define module specific macros here
85----------------------------------------------------------------------------*/
86
87
88/*----------------------------------------------------------------------------
89; DEFINES
90; Include all pre-processor statements here. Include conditional
91; compile variables also.
92----------------------------------------------------------------------------*/
93
94
95/*----------------------------------------------------------------------------
96; LOCAL FUNCTION DEFINITIONS
97; Function Prototype declaration
98----------------------------------------------------------------------------*/
99
100/*----------------------------------------------------------------------------
101; LOCAL STORE/BUFFER/POINTER DEFINITIONS
102; Variable declaration - defined here and used outside this module
103----------------------------------------------------------------------------*/
104
105/*----------------------------------------------------------------------------
106; EXTERNAL FUNCTION REFERENCES
107; Declare functions defined elsewhere and referenced in this module
108----------------------------------------------------------------------------*/
109
110/*----------------------------------------------------------------------------
111; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
112; Declare variables used in this module but defined elsewhere
113----------------------------------------------------------------------------*/
114
115/*----------------------------------------------------------------------------
116; FUNCTION CODE
117----------------------------------------------------------------------------*/
118
119void pvmp3_reorder(int32 xr[SUBBANDS_NUMBER*FILTERBANK_BANDS],
120                   granuleInfo *gr_info,
121                   int32  *used_freq_lines,
122                   mp3Header *info,
123                   int32  Scratch_mem[198])
124{
125    int32 sfreq =  info->version_x + (info->version_x << 1);
126    sfreq += info->sampling_frequency;
127
128    if (gr_info->window_switching_flag && (gr_info->block_type == 2))
129    {
130        int32   sfb_lines;
131        int32   freq;
132        int32   src_line;
133        int32   sfb;
134        if (gr_info->mixed_block_flag)
135        {
136            /* REORDERING FOR REST SWITCHED SHORT */
137            sfb = 3;  /* no reorder for low 2 subbands */
138            src_line = 36;
139        }
140        else
141        {  /* pure short */
142            sfb = 0;
143            src_line = 0;
144        }
145        int16 ct = src_line;
146
147        for (; sfb < 13; sfb++)
148        {
149            if (*used_freq_lines > 3*mp3_sfBandIndex[sfreq].s[sfb+1])
150            {
151                sfb_lines = mp3_sfBandIndex[sfreq].s[sfb+1]  - mp3_sfBandIndex[sfreq].s[sfb];
152
153                for (freq = 0; freq < 3*sfb_lines; freq += 3)
154                {
155                    int32 tmp1 = xr[src_line];
156                    int32 tmp2 = xr[src_line+(sfb_lines)];
157                    int32 tmp3 = xr[src_line+(sfb_lines<<1)];
158                    src_line++;
159                    Scratch_mem[freq  ] = tmp1;
160                    Scratch_mem[freq+1] = tmp2;
161                    Scratch_mem[freq+2] = tmp3;
162                }
163                src_line += (sfb_lines << 1);
164
165                pv_memcpy(&xr[ct], Scratch_mem, sfb_lines*3*sizeof(int32));
166                ct += sfb_lines + (sfb_lines << 1);
167
168            }
169            else
170            {
171
172                sfb_lines = mp3_sfBandIndex[sfreq].s[sfb+1]  - mp3_sfBandIndex[sfreq].s[sfb];
173
174                for (freq = 0; freq < 3*sfb_lines; freq += 3)
175                {
176                    int32 tmp1 = xr[src_line];
177                    int32 tmp2 = xr[src_line+(sfb_lines)];
178                    int32 tmp3 = xr[src_line+(sfb_lines<<1)];
179                    src_line++;
180                    Scratch_mem[freq  ] = tmp1;
181                    Scratch_mem[freq+1] = tmp2;
182                    Scratch_mem[freq+2] = tmp3;
183                }
184
185                pv_memcpy(&xr[ct], Scratch_mem, sfb_lines*3*sizeof(int32));
186
187                *used_freq_lines = mp3_sfBandIndex[sfreq].s[sfb+1] * 3;
188
189                sfb = 13;   /* force out of the for-loop */
190            }
191        }
192    }
193}
194
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197
198