3 * Copyright (c) 2001 Fabrice Bellard.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "bitstream.h" // for ff_reverse
28 /* from g711.c by SUN microsystems (unrestricted use) */
30 #define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */
31 #define QUANT_MASK (0xf) /* Quantization field mask. */
32 #define NSEGS (8) /* Number of A-law segments. */
33 #define SEG_SHIFT (4) /* Left shift for segment number. */
34 #define SEG_MASK (0x70) /* Segment field mask. */
36 #define BIAS (0x84) /* Bias for linear code. */
39 * alaw2linear() - Convert an A-law value to 16-bit linear PCM
42 static int alaw2linear(unsigned char a_val)
49 t = a_val & QUANT_MASK;
50 seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
51 if(seg) t= (t + t + 1 + 32) << (seg + 2);
52 else t= (t + t + 1 ) << 3;
54 return ((a_val & SIGN_BIT) ? t : -t);
57 static int ulaw2linear(unsigned char u_val)
61 /* Complement to obtain normal u-law value. */
65 * Extract and bias the quantization bits. Then
66 * shift up by the segment number and subtract out the bias.
68 t = ((u_val & QUANT_MASK) << 3) + BIAS;
69 t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
71 return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS));
74 /* 16384 entries per table */
75 static uint8_t *linear_to_alaw = NULL;
76 static int linear_to_alaw_ref = 0;
78 static uint8_t *linear_to_ulaw = NULL;
79 static int linear_to_ulaw_ref = 0;
81 static void build_xlaw_table(uint8_t *linear_to_xlaw,
82 int (*xlaw2linear)(unsigned char),
90 v1 = xlaw2linear(i ^ mask);
91 v2 = xlaw2linear((i + 1) ^ mask);
92 v = (v1 + v2 + 4) >> 3;
97 linear_to_xlaw[8192 + j] = (i ^ mask);
99 linear_to_xlaw[8192 - j] = (i ^ (mask ^ 0x80));
102 linear_to_xlaw[0] = linear_to_xlaw[1];
105 static int pcm_encode_init(AVCodecContext *avctx)
107 avctx->frame_size = 1;
108 switch(avctx->codec->id) {
109 case CODEC_ID_PCM_ALAW:
110 if (linear_to_alaw_ref == 0) {
111 linear_to_alaw = av_malloc(16384);
114 build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5);
116 linear_to_alaw_ref++;
118 case CODEC_ID_PCM_MULAW:
119 if (linear_to_ulaw_ref == 0) {
120 linear_to_ulaw = av_malloc(16384);
123 build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff);
125 linear_to_ulaw_ref++;
131 switch(avctx->codec->id) {
132 case CODEC_ID_PCM_S32LE:
133 case CODEC_ID_PCM_S32BE:
134 case CODEC_ID_PCM_U32LE:
135 case CODEC_ID_PCM_U32BE:
136 avctx->block_align = 4 * avctx->channels;
138 case CODEC_ID_PCM_S24LE:
139 case CODEC_ID_PCM_S24BE:
140 case CODEC_ID_PCM_U24LE:
141 case CODEC_ID_PCM_U24BE:
142 case CODEC_ID_PCM_S24DAUD:
143 avctx->block_align = 3 * avctx->channels;
145 case CODEC_ID_PCM_S16LE:
146 case CODEC_ID_PCM_S16BE:
147 case CODEC_ID_PCM_U16LE:
148 case CODEC_ID_PCM_U16BE:
149 avctx->block_align = 2 * avctx->channels;
151 case CODEC_ID_PCM_S8:
152 case CODEC_ID_PCM_U8:
153 case CODEC_ID_PCM_MULAW:
154 case CODEC_ID_PCM_ALAW:
155 avctx->block_align = avctx->channels;
161 avctx->coded_frame= avcodec_alloc_frame();
162 avctx->coded_frame->key_frame= 1;
167 static int pcm_encode_close(AVCodecContext *avctx)
169 av_freep(&avctx->coded_frame);
171 switch(avctx->codec->id) {
172 case CODEC_ID_PCM_ALAW:
173 if (--linear_to_alaw_ref == 0)
174 av_free(linear_to_alaw);
176 case CODEC_ID_PCM_MULAW:
177 if (--linear_to_ulaw_ref == 0)
178 av_free(linear_to_ulaw);
181 /* nothing to free */
188 * \brief convert samples from 16 bit
189 * \param bps byte per sample for the destination format, must be >= 2
190 * \param le 0 for big-, 1 for little-endian
191 * \param us 0 for signed, 1 for unsigned output
192 * \param samples input samples
193 * \param dst output samples
194 * \param n number of samples in samples buffer.
196 static inline void encode_from16(int bps, int le, int us,
197 short **samples, uint8_t **dst, int n) {
199 memset(*dst, 0, n * bps);
200 if (le) *dst += bps - 2;
202 register int v = *(*samples)++;
208 if (le) *dst -= bps - 2;
211 static int pcm_encode_frame(AVCodecContext *avctx,
212 unsigned char *frame, int buf_size, void *data)
214 int n, sample_size, v;
218 switch(avctx->codec->id) {
219 case CODEC_ID_PCM_S32LE:
220 case CODEC_ID_PCM_S32BE:
221 case CODEC_ID_PCM_U32LE:
222 case CODEC_ID_PCM_U32BE:
225 case CODEC_ID_PCM_S24LE:
226 case CODEC_ID_PCM_S24BE:
227 case CODEC_ID_PCM_U24LE:
228 case CODEC_ID_PCM_U24BE:
229 case CODEC_ID_PCM_S24DAUD:
232 case CODEC_ID_PCM_S16LE:
233 case CODEC_ID_PCM_S16BE:
234 case CODEC_ID_PCM_U16LE:
235 case CODEC_ID_PCM_U16BE:
242 n = buf_size / sample_size;
246 switch(avctx->codec->id) {
247 case CODEC_ID_PCM_S32LE:
248 encode_from16(4, 1, 0, &samples, &dst, n);
250 case CODEC_ID_PCM_S32BE:
251 encode_from16(4, 0, 0, &samples, &dst, n);
253 case CODEC_ID_PCM_U32LE:
254 encode_from16(4, 1, 1, &samples, &dst, n);
256 case CODEC_ID_PCM_U32BE:
257 encode_from16(4, 0, 1, &samples, &dst, n);
259 case CODEC_ID_PCM_S24LE:
260 encode_from16(3, 1, 0, &samples, &dst, n);
262 case CODEC_ID_PCM_S24BE:
263 encode_from16(3, 0, 0, &samples, &dst, n);
265 case CODEC_ID_PCM_U24LE:
266 encode_from16(3, 1, 1, &samples, &dst, n);
268 case CODEC_ID_PCM_U24BE:
269 encode_from16(3, 0, 1, &samples, &dst, n);
271 case CODEC_ID_PCM_S24DAUD:
273 uint32_t tmp = ff_reverse[*samples >> 8] +
274 (ff_reverse[*samples & 0xff] << 8);
275 tmp <<= 4; // sync flags would go here
284 case CODEC_ID_PCM_S16LE:
292 case CODEC_ID_PCM_S16BE:
300 case CODEC_ID_PCM_U16LE:
309 case CODEC_ID_PCM_U16BE:
318 case CODEC_ID_PCM_S8:
325 case CODEC_ID_PCM_U8:
328 dst[0] = (v >> 8) + 128;
332 case CODEC_ID_PCM_ALAW:
335 dst[0] = linear_to_alaw[(v + 32768) >> 2];
339 case CODEC_ID_PCM_MULAW:
342 dst[0] = linear_to_ulaw[(v + 32768) >> 2];
349 //avctx->frame_size = (dst - frame) / (sample_size * avctx->channels);
354 typedef struct PCMDecode {
358 static int pcm_decode_init(AVCodecContext * avctx)
360 PCMDecode *s = avctx->priv_data;
363 switch(avctx->codec->id) {
364 case CODEC_ID_PCM_ALAW:
366 s->table[i] = alaw2linear(i);
368 case CODEC_ID_PCM_MULAW:
370 s->table[i] = ulaw2linear(i);
379 * \brief convert samples to 16 bit
380 * \param bps byte per sample for the source format, must be >= 2
381 * \param le 0 for big-, 1 for little-endian
382 * \param us 0 for signed, 1 for unsigned input
383 * \param src input samples
384 * \param samples output samples
385 * \param src_len number of bytes in src
387 static inline void decode_to16(int bps, int le, int us,
388 uint8_t **src, short **samples, int src_len)
390 register int n = src_len / bps;
391 if (le) *src += bps - 2;
393 *(*samples)++ = ((*src)[le] << 8 | (*src)[1 - le]) - (us?0x8000:0);
396 if (le) *src -= bps - 2;
399 static int pcm_decode_frame(AVCodecContext *avctx,
400 void *data, int *data_size,
401 uint8_t *buf, int buf_size)
403 PCMDecode *s = avctx->priv_data;
411 if(buf_size > AVCODEC_MAX_AUDIO_FRAME_SIZE/2)
412 buf_size = AVCODEC_MAX_AUDIO_FRAME_SIZE/2;
414 switch(avctx->codec->id) {
415 case CODEC_ID_PCM_S32LE:
416 decode_to16(4, 1, 0, &src, &samples, buf_size);
418 case CODEC_ID_PCM_S32BE:
419 decode_to16(4, 0, 0, &src, &samples, buf_size);
421 case CODEC_ID_PCM_U32LE:
422 decode_to16(4, 1, 1, &src, &samples, buf_size);
424 case CODEC_ID_PCM_U32BE:
425 decode_to16(4, 0, 1, &src, &samples, buf_size);
427 case CODEC_ID_PCM_S24LE:
428 decode_to16(3, 1, 0, &src, &samples, buf_size);
430 case CODEC_ID_PCM_S24BE:
431 decode_to16(3, 0, 0, &src, &samples, buf_size);
433 case CODEC_ID_PCM_U24LE:
434 decode_to16(3, 1, 1, &src, &samples, buf_size);
436 case CODEC_ID_PCM_U24BE:
437 decode_to16(3, 0, 1, &src, &samples, buf_size);
439 case CODEC_ID_PCM_S24DAUD:
442 uint32_t v = src[0] << 16 | src[1] << 8 | src[2];
443 v >>= 4; // sync flags are here
444 *samples++ = ff_reverse[(v >> 8) & 0xff] +
445 (ff_reverse[v & 0xff] << 8);
449 case CODEC_ID_PCM_S16LE:
452 *samples++ = src[0] | (src[1] << 8);
456 case CODEC_ID_PCM_S16BE:
459 *samples++ = (src[0] << 8) | src[1];
463 case CODEC_ID_PCM_U16LE:
466 *samples++ = (src[0] | (src[1] << 8)) - 0x8000;
470 case CODEC_ID_PCM_U16BE:
473 *samples++ = ((src[0] << 8) | src[1]) - 0x8000;
477 case CODEC_ID_PCM_S8:
480 *samples++ = src[0] << 8;
484 case CODEC_ID_PCM_U8:
487 *samples++ = ((int)src[0] - 128) << 8;
491 case CODEC_ID_PCM_ALAW:
492 case CODEC_ID_PCM_MULAW:
495 *samples++ = s->table[src[0]];
502 *data_size = (uint8_t *)samples - (uint8_t *)data;
506 #define PCM_CODEC(id, name) \
507 AVCodec name ## _encoder = { \
517 AVCodec name ## _decoder = { \
528 PCM_CODEC(CODEC_ID_PCM_S32LE, pcm_s32le);
529 PCM_CODEC(CODEC_ID_PCM_S32BE, pcm_s32be);
530 PCM_CODEC(CODEC_ID_PCM_U32LE, pcm_u32le);
531 PCM_CODEC(CODEC_ID_PCM_U32BE, pcm_u32be);
532 PCM_CODEC(CODEC_ID_PCM_S24LE, pcm_s24le);
533 PCM_CODEC(CODEC_ID_PCM_S24BE, pcm_s24be);
534 PCM_CODEC(CODEC_ID_PCM_U24LE, pcm_u24le);
535 PCM_CODEC(CODEC_ID_PCM_U24BE, pcm_u24be);
536 PCM_CODEC(CODEC_ID_PCM_S24DAUD, pcm_s24daud);
537 PCM_CODEC(CODEC_ID_PCM_S16LE, pcm_s16le);
538 PCM_CODEC(CODEC_ID_PCM_S16BE, pcm_s16be);
539 PCM_CODEC(CODEC_ID_PCM_U16LE, pcm_u16le);
540 PCM_CODEC(CODEC_ID_PCM_U16BE, pcm_u16be);
541 PCM_CODEC(CODEC_ID_PCM_S8, pcm_s8);
542 PCM_CODEC(CODEC_ID_PCM_U8, pcm_u8);
543 PCM_CODEC(CODEC_ID_PCM_ALAW, pcm_alaw);
544 PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);