summaryrefslogtreecommitdiff
path: root/libavcodec/adx.c
blob: c8c7855903468357f93308a138b2fb5fd0b8a241 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
/*
 * ADX ADPCM codecs
 * Copyright (c) 2001,2003 BERO
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */
#include "avcodec.h"

/**
 * @file adx.c
 * SEGA CRI adx codecs.
 *
 * Reference documents:
 * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html
 * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/
 */

typedef struct {
    int s1,s2;
} PREV;

typedef struct {
    PREV prev[2];
    int header_parsed;
    unsigned char dec_temp[18*2];
    unsigned short enc_temp[32*2];
    int in_temp;
} ADXContext;

//#define    BASEVOL    0x11e0
#define    BASEVOL   0x4000
#define    SCALE1    0x7298
#define    SCALE2    0x3350

#define    CLIP(s)    if (s>32767) s=32767; else if (s<-32768) s=-32768

/* 18 bytes <-> 32 samples */

#ifdef CONFIG_ENCODERS
static void adx_encode(unsigned char *adx,const short *wav,PREV *prev)
{
    int scale;
    int i;
    int s0,s1,s2,d;
    int max=0;
    int min=0;
    int data[32];

    s1 = prev->s1;
    s2 = prev->s2;
    for(i=0;i<32;i++) {
        s0 = wav[i];
        d = ((s0<<14) - SCALE1*s1 + SCALE2*s2)/BASEVOL;
        data[i]=d;
        if (max<d) max=d;
        if (min>d) min=d;
        s2 = s1;
        s1 = s0;
    }
    prev->s1 = s1;
    prev->s2 = s2;

    /* -8..+7 */

    if (max==0 && min==0) {
        memset(adx,0,18);
        return;
    }

    if (max/7>-min/8) scale = max/7;
    else scale = -min/8;

    if (scale==0) scale=1;

    adx[0] = scale>>8;
    adx[1] = scale;

    for(i=0;i<16;i++) {
        adx[i+2] = ((data[i*2]/scale)<<4) | ((data[i*2+1]/scale)&0xf);
    }
}
#endif //CONFIG_ENCODERS

static void adx_decode(short *out,const unsigned char *in,PREV *prev)
{
    int scale = ((in[0]<<8)|(in[1]));
    int i;
    int s0,s1,s2,d;

//    printf("%x ",scale);

    in+=2;
    s1 = prev->s1;
    s2 = prev->s2;
    for(i=0;i<16;i++) {
        d = in[i];
        // d>>=4; if (d&8) d-=16;
        d = ((signed char)d >> 4);
        s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14;
        CLIP(s0);
        *out++=s0;
        s2 = s1;
        s1 = s0;

        d = in[i];
        //d&=15; if (d&8) d-=16;
        d = ((signed char)(d<<4) >> 4);
        s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14;
        CLIP(s0);
        *out++=s0;
        s2 = s1;
        s1 = s0;
    }
    prev->s1 = s1;
    prev->s2 = s2;

}

static void adx_decode_stereo(short *out,const unsigned char *in,PREV *prev)
{
    short tmp[32*2];
    int i;

    adx_decode(tmp   ,in   ,prev);
    adx_decode(tmp+32,in+18,prev+1);
    for(i=0;i<32;i++) {
        out[i*2]   = tmp[i];
        out[i*2+1] = tmp[i+32];
    }
}

#ifdef CONFIG_ENCODERS

static void write_long(unsigned char *p,uint32_t v)
{
    p[0] = v>>24;
    p[1] = v>>16;
    p[2] = v>>8;
    p[3] = v;
}

static int adx_encode_header(AVCodecContext *avctx,unsigned char *buf,size_t bufsize)
{
#if 0
    struct {
        uint32_t offset; /* 0x80000000 + sample start - 4 */
        unsigned char unknown1[3]; /* 03 12 04 */
        unsigned char channel; /* 1 or 2 */
        uint32_t freq;
        uint32_t size;
        uint32_t unknown2; /* 01 f4 03 00 */
        uint32_t unknown3; /* 00 00 00 00 */
        uint32_t unknown4; /* 00 00 00 00 */

    /* if loop
        unknown3 00 15 00 01
        unknown4 00 00 00 01
        long loop_start_sample;
        long loop_start_byte;
        long loop_end_sample;
        long loop_end_byte;
        long
    */
    } adxhdr; /* big endian */
    /* offset-6 "(c)CRI" */
#endif
    write_long(buf+0x00,0x80000000|0x20);
    write_long(buf+0x04,0x03120400|avctx->channels);
    write_long(buf+0x08,avctx->sample_rate);
    write_long(buf+0x0c,0); /* FIXME: set after */
    write_long(buf+0x10,0x01040300);
    write_long(buf+0x14,0x00000000);
    write_long(buf+0x18,0x00000000);
    memcpy(buf+0x1c,"\0\0(c)CRI",8);
    return 0x20+4;
}

static int adx_decode_init(AVCodecContext *avctx);
static int adx_encode_init(AVCodecContext *avctx)
{
    if (avctx->channels > 2)
        return -1; /* only stereo or mono =) */
    avctx->frame_size = 32;

    avctx->coded_frame= avcodec_alloc_frame();
    avctx->coded_frame->key_frame= 1;

//    avctx->bit_rate = avctx->sample_rate*avctx->channels*18*8/32;

    av_log(avctx, AV_LOG_DEBUG, "adx encode init\n");
    adx_decode_init(avctx);

    return 0;
}

static int adx_encode_close(AVCodecContext *avctx)
{
    av_freep(&avctx->coded_frame);

    return 0;
}

static int adx_encode_frame(AVCodecContext *avctx,
                uint8_t *frame, int buf_size, void *data)
{
    ADXContext *c = avctx->priv_data;
    const short *samples = data;
    unsigned char *dst = frame;
    int rest = avctx->frame_size;

/*
    input data size =
    ffmpeg.c: do_audio_out()
    frame_bytes = enc->frame_size * 2 * enc->channels;
*/

//    printf("sz=%d ",buf_size); fflush(stdout);
    if (!c->header_parsed) {
        int hdrsize = adx_encode_header(avctx,dst,buf_size);
        dst+=hdrsize;
        c->header_parsed = 1;
    }

    if (avctx->channels==1) {
        while(rest>=32) {
            adx_encode(dst,samples,c->prev);
            dst+=18;
            samples+=32;
            rest-=32;
        }
    } else {
        while(rest>=32*2) {
            short tmpbuf[32*2];
            int i;

            for(i=0;i<32;i++) {
                tmpbuf[i] = samples[i*2];
                tmpbuf[i+32] = samples[i*2+1];
            }

            adx_encode(dst,tmpbuf,c->prev);
            adx_encode(dst+18,tmpbuf+32,c->prev+1);
            dst+=18*2;
            samples+=32*2;
            rest-=32*2;
        }
    }
    return dst-frame;
}

#endif //CONFIG_ENCODERS

static uint32_t read_long(const unsigned char *p)
{
    return (p[0]<<24)|(p[1]<<16)|(p[2]<<8)|p[3];
}

static int is_adx(const unsigned char *buf,size_t bufsize)
{
    int    offset;

    if (buf[0]!=0x80) return 0;
    offset = (read_long(buf)^0x80000000)+4;
    if (bufsize<offset || memcmp(buf+offset-6,"(c)CRI",6)) return 0;
    return offset;
}

/* return data offset or 6 */
static int adx_decode_header(AVCodecContext *avctx,const unsigned char *buf,size_t bufsize)
{
    int offset;
    int channels,freq,size;

    offset = is_adx(buf,bufsize);
    if (offset==0) return 0;

    channels = buf[7];
    freq = read_long(buf+8);
    size = read_long(buf+12);

//    printf("freq=%d ch=%d\n",freq,channels);

    avctx->sample_rate = freq;
    avctx->channels = channels;
    avctx->bit_rate = freq*channels*18*8/32;
//    avctx->frame_size = 18*channels;

    return offset;
}

static int adx_decode_init(AVCodecContext * avctx)
{
    ADXContext *c = avctx->priv_data;

//    printf("adx_decode_init\n"); fflush(stdout);
    c->prev[0].s1 = 0;
    c->prev[0].s2 = 0;
    c->prev[1].s1 = 0;
    c->prev[1].s2 = 0;
    c->header_parsed = 0;
    c->in_temp = 0;
    return 0;
}

#if 0
static void dump(unsigned char *buf,size_t len)
{
    int i;
    for(i=0;i<len;i++) {
        if ((i&15)==0) av_log(NULL, AV_LOG_DEBUG, "%04x  ",i);
        av_log(NULL, AV_LOG_DEBUG, "%02x ",buf[i]);
        if ((i&15)==15) av_log(NULL, AV_LOG_DEBUG, "\n");
    }
    av_log(NULL, AV_LOG_ERROR, "\n");
}
#endif

static int adx_decode_frame(AVCodecContext *avctx,
                void *data, int *data_size,
                uint8_t *buf0, int buf_size)
{
    ADXContext *c = avctx->priv_data;
    short *samples = data;
    const uint8_t *buf = buf0;
    int rest = buf_size;

    if (!c->header_parsed) {
        int hdrsize = adx_decode_header(avctx,buf,rest);
        if (hdrsize==0) return -1;
        c->header_parsed = 1;
        buf  += hdrsize;
        rest -= hdrsize;
    }

    if (c->in_temp) {
        int copysize = 18*avctx->channels - c->in_temp;
        memcpy(c->dec_temp+c->in_temp,buf,copysize);
        rest -= copysize;
        buf  += copysize;
        if (avctx->channels==1) {
            adx_decode(samples,c->dec_temp,c->prev);
            samples += 32;
        } else {
            adx_decode_stereo(samples,c->dec_temp,c->prev);
            samples += 32*2;
        }
    }
    //
    if (avctx->channels==1) {
        while(rest>=18) {
            adx_decode(samples,buf,c->prev);
            rest-=18;
            buf+=18;
            samples+=32;
        }
    } else {
        while(rest>=18*2) {
            adx_decode_stereo(samples,buf,c->prev);
            rest-=18*2;
            buf+=18*2;
            samples+=32*2;
        }
    }
    //
    c->in_temp = rest;
    if (rest) {
        memcpy(c->dec_temp,buf,rest);
        buf+=rest;
    }
    *data_size = (uint8_t*)samples - (uint8_t*)data;
//    printf("%d:%d ",buf-buf0,*data_size); fflush(stdout);
    return buf-buf0;
}

#ifdef CONFIG_ENCODERS
AVCodec adpcm_adx_encoder = {
    "adpcm_adx",
    CODEC_TYPE_AUDIO,
    CODEC_ID_ADPCM_ADX,
    sizeof(ADXContext),
    adx_encode_init,
    adx_encode_frame,
    adx_encode_close,
    NULL,
};
#endif //CONFIG_ENCODERS

AVCodec adpcm_adx_decoder = {
    "adpcm_adx",
    CODEC_TYPE_AUDIO,
    CODEC_ID_ADPCM_ADX,
    sizeof(ADXContext),
    adx_decode_init,
    NULL,
    NULL,
    adx_decode_frame,
};