1 /* Copyright (C) 2002 Jean-Marc Valin
2    File: speex_header.c
3    Describes the Speex header
4 
5    Redistribution and use in source and binary forms, with or without
6    modification, are permitted provided that the following conditions
7    are met:
8 
9    - Redistributions of source code must retain the above copyright
10    notice, this list of conditions and the following disclaimer.
11 
12    - Redistributions in binary form must reproduce the above copyright
13    notice, this list of conditions and the following disclaimer in the
14    documentation and/or other materials provided with the distribution.
15 
16    - Neither the name of the Xiph.org Foundation nor the names of its
17    contributors may be used to endorse or promote products derived from
18    this software without specific prior written permission.
19 
20    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23    A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
24    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 
32 */
33 
34 #ifdef HAVE_CONFIG_H
35 #include "config.h"
36 #endif
37 
38 #include "arch.h"
39 #include <speex/speex_header.h>
40 #include <speex/speex.h>
41 #include "os_support.h"
42 
43 #ifndef NULL
44 #define NULL 0
45 #endif
46 
47 /** Convert little endian */
le_int(spx_int32_t i)48 static inline spx_int32_t le_int(spx_int32_t i)
49 {
50 #if !defined(__LITTLE_ENDIAN__) && ( defined(WORDS_BIGENDIAN) || defined(__BIG_ENDIAN__) )
51    spx_uint32_t ui, ret;
52    ui = i;
53    ret =  ui>>24;
54    ret |= (ui>>8)&0x0000ff00;
55    ret |= (ui<<8)&0x00ff0000;
56    ret |= (ui<<24);
57    return ret;
58 #else
59    return i;
60 #endif
61 }
62 
63 #define ENDIAN_SWITCH(x) {x=le_int(x);}
64 
65 
66 /*
67 typedef struct SpeexHeader {
68    char speex_string[8];
69    char speex_version[SPEEX_HEADER_VERSION_LENGTH];
70    int speex_version_id;
71    int header_size;
72    int rate;
73    int mode;
74    int mode_bitstream_version;
75    int nb_channels;
76    int bitrate;
77    int frame_size;
78    int vbr;
79    int frames_per_packet;
80    int extra_headers;
81    int reserved1;
82    int reserved2;
83 } SpeexHeader;
84 */
85 
speex_init_header(SpeexHeader * header,int rate,int nb_channels,const SpeexMode * m)86 void speex_init_header(SpeexHeader *header, int rate, int nb_channels, const SpeexMode *m)
87 {
88    int i;
89    const char *h="Speex   ";
90    /*
91    strncpy(header->speex_string, "Speex   ", 8);
92    strncpy(header->speex_version, SPEEX_VERSION, SPEEX_HEADER_VERSION_LENGTH-1);
93    header->speex_version[SPEEX_HEADER_VERSION_LENGTH-1]=0;
94    */
95    for (i=0;i<8;i++)
96       header->speex_string[i]=h[i];
97    for (i=0;i<SPEEX_HEADER_VERSION_LENGTH-1 && SPEEX_VERSION[i];i++)
98       header->speex_version[i]=SPEEX_VERSION[i];
99    for (;i<SPEEX_HEADER_VERSION_LENGTH;i++)
100       header->speex_version[i]=0;
101 
102    header->speex_version_id = 1;
103    header->header_size = sizeof(SpeexHeader);
104 
105    header->rate = rate;
106    header->mode = m->modeID;
107    header->mode_bitstream_version = m->bitstream_version;
108    if (m->modeID<0)
109       speex_warning("This mode is meant to be used alone");
110    header->nb_channels = nb_channels;
111    header->bitrate = -1;
112    speex_mode_query(m, SPEEX_MODE_FRAME_SIZE, &header->frame_size);
113    header->vbr = 0;
114 
115    header->frames_per_packet = 0;
116    header->extra_headers = 0;
117    header->reserved1 = 0;
118    header->reserved2 = 0;
119 }
120 
speex_header_to_packet(SpeexHeader * header,int * size)121 char *speex_header_to_packet(SpeexHeader *header, int *size)
122 {
123    SpeexHeader *le_header;
124    le_header = (SpeexHeader*)speex_alloc(sizeof(SpeexHeader));
125 
126    SPEEX_COPY(le_header, header, 1);
127 
128    /*Make sure everything is now little-endian*/
129    ENDIAN_SWITCH(le_header->speex_version_id);
130    ENDIAN_SWITCH(le_header->header_size);
131    ENDIAN_SWITCH(le_header->rate);
132    ENDIAN_SWITCH(le_header->mode);
133    ENDIAN_SWITCH(le_header->mode_bitstream_version);
134    ENDIAN_SWITCH(le_header->nb_channels);
135    ENDIAN_SWITCH(le_header->bitrate);
136    ENDIAN_SWITCH(le_header->frame_size);
137    ENDIAN_SWITCH(le_header->vbr);
138    ENDIAN_SWITCH(le_header->frames_per_packet);
139    ENDIAN_SWITCH(le_header->extra_headers);
140 
141    *size = sizeof(SpeexHeader);
142    return (char *)le_header;
143 }
144 
speex_packet_to_header(char * packet,int size)145 SpeexHeader *speex_packet_to_header(char *packet, int size)
146 {
147    int i;
148    SpeexHeader *le_header;
149    const char *h = "Speex   ";
150    for (i=0;i<8;i++)
151       if (packet[i]!=h[i])
152       {
153          speex_notify("This doesn't look like a Speex file");
154          return NULL;
155       }
156 
157    /*FIXME: Do we allow larger headers?*/
158    if (size < (int)sizeof(SpeexHeader))
159    {
160       speex_notify("Speex header too small");
161       return NULL;
162    }
163 
164    le_header = (SpeexHeader*)speex_alloc(sizeof(SpeexHeader));
165 
166    SPEEX_COPY(le_header, (SpeexHeader*)packet, 1);
167 
168    /*Make sure everything is converted correctly from little-endian*/
169    ENDIAN_SWITCH(le_header->speex_version_id);
170    ENDIAN_SWITCH(le_header->header_size);
171    ENDIAN_SWITCH(le_header->rate);
172    ENDIAN_SWITCH(le_header->mode);
173    ENDIAN_SWITCH(le_header->mode_bitstream_version);
174    ENDIAN_SWITCH(le_header->nb_channels);
175    ENDIAN_SWITCH(le_header->bitrate);
176    ENDIAN_SWITCH(le_header->frame_size);
177    ENDIAN_SWITCH(le_header->vbr);
178    ENDIAN_SWITCH(le_header->frames_per_packet);
179    ENDIAN_SWITCH(le_header->extra_headers);
180 
181    return le_header;
182 
183 }
184 
speex_header_free(void * ptr)185 void speex_header_free(void *ptr)
186 {
187    speex_free(ptr);
188 }
189