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/*
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 * PCM codecs
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 * Copyright (c) 2001 Fabrice Bellard.
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21

    
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/**
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 * @file pcm.c
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 * PCM codecs
25
 */
26

    
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#include "avcodec.h"
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#include "bitstream.h" // for ff_reverse
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#include "bytestream.h"
30

    
31
/* from g711.c by SUN microsystems (unrestricted use) */
32

    
33
#define         SIGN_BIT        (0x80)      /* Sign bit for a A-law byte. */
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#define         QUANT_MASK      (0xf)       /* Quantization field mask. */
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#define         NSEGS           (8)         /* Number of A-law segments. */
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#define         SEG_SHIFT       (4)         /* Left shift for segment number. */
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#define         SEG_MASK        (0x70)      /* Segment field mask. */
38

    
39
#define         BIAS            (0x84)      /* Bias for linear code. */
40

    
41
/*
42
 * alaw2linear() - Convert an A-law value to 16-bit linear PCM
43
 *
44
 */
45
static int alaw2linear(unsigned char a_val)
46
{
47
        int t;
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        int seg;
49

    
50
        a_val ^= 0x55;
51

    
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        t = a_val & QUANT_MASK;
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        seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
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        if(seg) t= (t + t + 1 + 32) << (seg + 2);
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        else    t= (t + t + 1     ) << 3;
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        return ((a_val & SIGN_BIT) ? t : -t);
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}
59

    
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static int ulaw2linear(unsigned char u_val)
61
{
62
        int t;
63

    
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        /* Complement to obtain normal u-law value. */
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        u_val = ~u_val;
66

    
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        /*
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         * Extract and bias the quantization bits. Then
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         * shift up by the segment number and subtract out the bias.
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         */
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        t = ((u_val & QUANT_MASK) << 3) + BIAS;
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        t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
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        return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS));
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}
76

    
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/* 16384 entries per table */
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static uint8_t linear_to_alaw[16384];
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static uint8_t linear_to_ulaw[16384];
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static void build_xlaw_table(uint8_t *linear_to_xlaw,
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                             int (*xlaw2linear)(unsigned char),
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                             int mask)
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{
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    int i, j, v, v1, v2;
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    j = 0;
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    for(i=0;i<128;i++) {
89
        if (i != 127) {
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            v1 = xlaw2linear(i ^ mask);
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            v2 = xlaw2linear((i + 1) ^ mask);
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            v = (v1 + v2 + 4) >> 3;
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        } else {
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            v = 8192;
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        }
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        for(;j<v;j++) {
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            linear_to_xlaw[8192 + j] = (i ^ mask);
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            if (j > 0)
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                linear_to_xlaw[8192 - j] = (i ^ (mask ^ 0x80));
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        }
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    }
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    linear_to_xlaw[0] = linear_to_xlaw[1];
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}
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static int pcm_encode_init(AVCodecContext *avctx)
106
{
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    avctx->frame_size = 1;
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    switch(avctx->codec->id) {
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    case CODEC_ID_PCM_ALAW:
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        build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5);
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        break;
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    case CODEC_ID_PCM_MULAW:
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        build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff);
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        break;
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    default:
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        break;
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    }
118

    
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    switch(avctx->codec->id) {
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    case CODEC_ID_PCM_S32LE:
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    case CODEC_ID_PCM_S32BE:
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    case CODEC_ID_PCM_U32LE:
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    case CODEC_ID_PCM_U32BE:
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        avctx->block_align = 4 * avctx->channels;
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        break;
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    case CODEC_ID_PCM_S24LE:
127
    case CODEC_ID_PCM_S24BE:
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    case CODEC_ID_PCM_U24LE:
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    case CODEC_ID_PCM_U24BE:
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    case CODEC_ID_PCM_S24DAUD:
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        avctx->block_align = 3 * avctx->channels;
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        break;
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    case CODEC_ID_PCM_S16LE:
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    case CODEC_ID_PCM_S16BE:
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    case CODEC_ID_PCM_U16LE:
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    case CODEC_ID_PCM_U16BE:
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        avctx->block_align = 2 * avctx->channels;
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        break;
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    case CODEC_ID_PCM_S8:
140
    case CODEC_ID_PCM_U8:
141
    case CODEC_ID_PCM_MULAW:
142
    case CODEC_ID_PCM_ALAW:
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        avctx->block_align = avctx->channels;
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        break;
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    default:
146
        break;
147
    }
148

    
149
    avctx->coded_frame= avcodec_alloc_frame();
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    avctx->coded_frame->key_frame= 1;
151

    
152
    return 0;
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}
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static int pcm_encode_close(AVCodecContext *avctx)
156
{
157
    av_freep(&avctx->coded_frame);
158

    
159
    return 0;
160
}
161

    
162
/**
163
 * \brief convert samples from 16 bit
164
 * \param bps byte per sample for the destination format, must be >= 2
165
 * \param le 0 for big-, 1 for little-endian
166
 * \param us 0 for signed, 1 for unsigned output
167
 * \param samples input samples
168
 * \param dst output samples
169
 * \param n number of samples in samples buffer.
170
 */
171
static inline void encode_from16(int bps, int le, int us,
172
                               short **samples, uint8_t **dst, int n) {
173
    int usum = us ? 0x8000 : 0;
174
    if (bps > 2)
175
        memset(*dst, 0, n * bps);
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    if (le) *dst += bps - 2;
177
    for(;n>0;n--) {
178
        register int v = *(*samples)++;
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        v += usum;
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        if (le) AV_WL16(*dst, v);
181
        else    AV_WB16(*dst, v);
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        *dst += bps;
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    }
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    if (le) *dst -= bps - 2;
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}
186

    
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static int pcm_encode_frame(AVCodecContext *avctx,
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                            unsigned char *frame, int buf_size, void *data)
189
{
190
    int n, sample_size, v;
191
    short *samples;
192
    unsigned char *dst;
193

    
194
    switch(avctx->codec->id) {
195
    case CODEC_ID_PCM_S32LE:
196
    case CODEC_ID_PCM_S32BE:
197
    case CODEC_ID_PCM_U32LE:
198
    case CODEC_ID_PCM_U32BE:
199
        sample_size = 4;
200
        break;
201
    case CODEC_ID_PCM_S24LE:
202
    case CODEC_ID_PCM_S24BE:
203
    case CODEC_ID_PCM_U24LE:
204
    case CODEC_ID_PCM_U24BE:
205
    case CODEC_ID_PCM_S24DAUD:
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        sample_size = 3;
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        break;
208
    case CODEC_ID_PCM_S16LE:
209
    case CODEC_ID_PCM_S16BE:
210
    case CODEC_ID_PCM_U16LE:
211
    case CODEC_ID_PCM_U16BE:
212
        sample_size = 2;
213
        break;
214
    default:
215
        sample_size = 1;
216
        break;
217
    }
218
    n = buf_size / sample_size;
219
    samples = data;
220
    dst = frame;
221

    
222
    switch(avctx->codec->id) {
223
    case CODEC_ID_PCM_S32LE:
224
        encode_from16(4, 1, 0, &samples, &dst, n);
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        break;
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    case CODEC_ID_PCM_S32BE:
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        encode_from16(4, 0, 0, &samples, &dst, n);
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        break;
229
    case CODEC_ID_PCM_U32LE:
230
        encode_from16(4, 1, 1, &samples, &dst, n);
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        break;
232
    case CODEC_ID_PCM_U32BE:
233
        encode_from16(4, 0, 1, &samples, &dst, n);
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        break;
235
    case CODEC_ID_PCM_S24LE:
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        encode_from16(3, 1, 0, &samples, &dst, n);
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        break;
238
    case CODEC_ID_PCM_S24BE:
239
        encode_from16(3, 0, 0, &samples, &dst, n);
240
        break;
241
    case CODEC_ID_PCM_U24LE:
242
        encode_from16(3, 1, 1, &samples, &dst, n);
243
        break;
244
    case CODEC_ID_PCM_U24BE:
245
        encode_from16(3, 0, 1, &samples, &dst, n);
246
        break;
247
    case CODEC_ID_PCM_S24DAUD:
248
        for(;n>0;n--) {
249
            uint32_t tmp = ff_reverse[*samples >> 8] +
250
                           (ff_reverse[*samples & 0xff] << 8);
251
            tmp <<= 4; // sync flags would go here
252
            bytestream_put_be24(&dst, tmp);
253
            samples++;
254
        }
255
        break;
256
    case CODEC_ID_PCM_S16LE:
257
        for(;n>0;n--) {
258
            v = *samples++;
259
            bytestream_put_le16(&dst, v);
260
        }
261
        break;
262
    case CODEC_ID_PCM_S16BE:
263
        for(;n>0;n--) {
264
            v = *samples++;
265
            bytestream_put_be16(&dst, v);
266
        }
267
        break;
268
    case CODEC_ID_PCM_U16LE:
269
        for(;n>0;n--) {
270
            v = *samples++;
271
            v += 0x8000;
272
            bytestream_put_le16(&dst, v);
273
        }
274
        break;
275
    case CODEC_ID_PCM_U16BE:
276
        for(;n>0;n--) {
277
            v = *samples++;
278
            v += 0x8000;
279
            bytestream_put_be16(&dst, v);
280
        }
281
        break;
282
    case CODEC_ID_PCM_S8:
283
        for(;n>0;n--) {
284
            v = *samples++;
285
            *dst++ = v >> 8;
286
        }
287
        break;
288
    case CODEC_ID_PCM_U8:
289
        for(;n>0;n--) {
290
            v = *samples++;
291
            *dst++ = (v >> 8) + 128;
292
        }
293
        break;
294
    case CODEC_ID_PCM_ALAW:
295
        for(;n>0;n--) {
296
            v = *samples++;
297
            *dst++ = linear_to_alaw[(v + 32768) >> 2];
298
        }
299
        break;
300
    case CODEC_ID_PCM_MULAW:
301
        for(;n>0;n--) {
302
            v = *samples++;
303
            *dst++ = linear_to_ulaw[(v + 32768) >> 2];
304
        }
305
        break;
306
    default:
307
        return -1;
308
    }
309
    //avctx->frame_size = (dst - frame) / (sample_size * avctx->channels);
310

    
311
    return dst - frame;
312
}
313

    
314
typedef struct PCMDecode {
315
    short table[256];
316
} PCMDecode;
317

    
318
static int pcm_decode_init(AVCodecContext * avctx)
319
{
320
    PCMDecode *s = avctx->priv_data;
321
    int i;
322

    
323
    switch(avctx->codec->id) {
324
    case CODEC_ID_PCM_ALAW:
325
        for(i=0;i<256;i++)
326
            s->table[i] = alaw2linear(i);
327
        break;
328
    case CODEC_ID_PCM_MULAW:
329
        for(i=0;i<256;i++)
330
            s->table[i] = ulaw2linear(i);
331
        break;
332
    default:
333
        break;
334
    }
335
    return 0;
336
}
337

    
338
/**
339
 * \brief convert samples to 16 bit
340
 * \param bps byte per sample for the source format, must be >= 2
341
 * \param le 0 for big-, 1 for little-endian
342
 * \param us 0 for signed, 1 for unsigned input
343
 * \param src input samples
344
 * \param samples output samples
345
 * \param src_len number of bytes in src
346
 */
347
static inline void decode_to16(int bps, int le, int us,
348
                               uint8_t **src, short **samples, int src_len)
349
{
350
    int usum = us ? -0x8000 : 0;
351
    register int n = src_len / bps;
352
    if (le) *src += bps - 2;
353
    for(;n>0;n--) {
354
        register int v;
355
        if (le) v = AV_RL16(*src);
356
        else    v = AV_RB16(*src);
357
        v += usum;
358
        *(*samples)++ = v;
359
        *src += bps;
360
    }
361
    if (le) *src -= bps - 2;
362
}
363

    
364
static int pcm_decode_frame(AVCodecContext *avctx,
365
                            void *data, int *data_size,
366
                            uint8_t *buf, int buf_size)
367
{
368
    PCMDecode *s = avctx->priv_data;
369
    int n;
370
    short *samples;
371
    uint8_t *src;
372

    
373
    samples = data;
374
    src = buf;
375

    
376
    n= av_get_bits_per_sample(avctx->codec_id)/8;
377
    if(n && buf_size % n){
378
        av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
379
        return -1;
380
    }
381

    
382
    buf_size= FFMIN(buf_size, *data_size/2);
383
    *data_size=0;
384

    
385
    switch(avctx->codec->id) {
386
    case CODEC_ID_PCM_S32LE:
387
        decode_to16(4, 1, 0, &src, &samples, buf_size);
388
        break;
389
    case CODEC_ID_PCM_S32BE:
390
        decode_to16(4, 0, 0, &src, &samples, buf_size);
391
        break;
392
    case CODEC_ID_PCM_U32LE:
393
        decode_to16(4, 1, 1, &src, &samples, buf_size);
394
        break;
395
    case CODEC_ID_PCM_U32BE:
396
        decode_to16(4, 0, 1, &src, &samples, buf_size);
397
        break;
398
    case CODEC_ID_PCM_S24LE:
399
        decode_to16(3, 1, 0, &src, &samples, buf_size);
400
        break;
401
    case CODEC_ID_PCM_S24BE:
402
        decode_to16(3, 0, 0, &src, &samples, buf_size);
403
        break;
404
    case CODEC_ID_PCM_U24LE:
405
        decode_to16(3, 1, 1, &src, &samples, buf_size);
406
        break;
407
    case CODEC_ID_PCM_U24BE:
408
        decode_to16(3, 0, 1, &src, &samples, buf_size);
409
        break;
410
    case CODEC_ID_PCM_S24DAUD:
411
        n = buf_size / 3;
412
        for(;n>0;n--) {
413
          uint32_t v = bytestream_get_be24(&src);
414
          v >>= 4; // sync flags are here
415
          *samples++ = ff_reverse[(v >> 8) & 0xff] +
416
                       (ff_reverse[v & 0xff] << 8);
417
        }
418
        break;
419
    case CODEC_ID_PCM_S16LE:
420
        n = buf_size >> 1;
421
        for(;n>0;n--) {
422
            *samples++ = bytestream_get_le16(&src);
423
        }
424
        break;
425
    case CODEC_ID_PCM_S16BE:
426
        n = buf_size >> 1;
427
        for(;n>0;n--) {
428
            *samples++ = bytestream_get_be16(&src);
429
        }
430
        break;
431
    case CODEC_ID_PCM_U16LE:
432
        n = buf_size >> 1;
433
        for(;n>0;n--) {
434
            *samples++ = bytestream_get_le16(&src) - 0x8000;
435
        }
436
        break;
437
    case CODEC_ID_PCM_U16BE:
438
        n = buf_size >> 1;
439
        for(;n>0;n--) {
440
            *samples++ = bytestream_get_be16(&src) - 0x8000;
441
        }
442
        break;
443
    case CODEC_ID_PCM_S8:
444
        n = buf_size;
445
        for(;n>0;n--) {
446
            *samples++ = *src++ << 8;
447
        }
448
        break;
449
    case CODEC_ID_PCM_U8:
450
        n = buf_size;
451
        for(;n>0;n--) {
452
            *samples++ = ((int)*src++ - 128) << 8;
453
        }
454
        break;
455
    case CODEC_ID_PCM_ALAW:
456
    case CODEC_ID_PCM_MULAW:
457
        n = buf_size;
458
        for(;n>0;n--) {
459
            *samples++ = s->table[*src++];
460
        }
461
        break;
462
    default:
463
        return -1;
464
    }
465
    *data_size = (uint8_t *)samples - (uint8_t *)data;
466
    return src - buf;
467
}
468

    
469
#define PCM_CODEC(id, name)                     \
470
AVCodec name ## _encoder = {                    \
471
    #name,                                      \
472
    CODEC_TYPE_AUDIO,                           \
473
    id,                                         \
474
    0,                                          \
475
    pcm_encode_init,                            \
476
    pcm_encode_frame,                           \
477
    pcm_encode_close,                           \
478
    NULL,                                       \
479
};                                              \
480
AVCodec name ## _decoder = {                    \
481
    #name,                                      \
482
    CODEC_TYPE_AUDIO,                           \
483
    id,                                         \
484
    sizeof(PCMDecode),                          \
485
    pcm_decode_init,                            \
486
    NULL,                                       \
487
    NULL,                                       \
488
    pcm_decode_frame,                           \
489
}
490

    
491
PCM_CODEC(CODEC_ID_PCM_S32LE, pcm_s32le);
492
PCM_CODEC(CODEC_ID_PCM_S32BE, pcm_s32be);
493
PCM_CODEC(CODEC_ID_PCM_U32LE, pcm_u32le);
494
PCM_CODEC(CODEC_ID_PCM_U32BE, pcm_u32be);
495
PCM_CODEC(CODEC_ID_PCM_S24LE, pcm_s24le);
496
PCM_CODEC(CODEC_ID_PCM_S24BE, pcm_s24be);
497
PCM_CODEC(CODEC_ID_PCM_U24LE, pcm_u24le);
498
PCM_CODEC(CODEC_ID_PCM_U24BE, pcm_u24be);
499
PCM_CODEC(CODEC_ID_PCM_S24DAUD, pcm_s24daud);
500
PCM_CODEC(CODEC_ID_PCM_S16LE, pcm_s16le);
501
PCM_CODEC(CODEC_ID_PCM_S16BE, pcm_s16be);
502
PCM_CODEC(CODEC_ID_PCM_U16LE, pcm_u16le);
503
PCM_CODEC(CODEC_ID_PCM_U16BE, pcm_u16be);
504
PCM_CODEC(CODEC_ID_PCM_S8, pcm_s8);
505
PCM_CODEC(CODEC_ID_PCM_U8, pcm_u8);
506
PCM_CODEC(CODEC_ID_PCM_ALAW, pcm_alaw);
507
PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);
508

    
509
#undef PCM_CODEC