3 * Copyright (c) 2001 Fabrice Bellard.
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #include "bitstream.h" // for ff_reverse
30 /* from g711.c by SUN microsystems (unrestricted use) */
32 #define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */
33 #define QUANT_MASK (0xf) /* Quantization field mask. */
34 #define NSEGS (8) /* Number of A-law segments. */
35 #define SEG_SHIFT (4) /* Left shift for segment number. */
36 #define SEG_MASK (0x70) /* Segment field mask. */
38 #define BIAS (0x84) /* Bias for linear code. */
41 * alaw2linear() - Convert an A-law value to 16-bit linear PCM
44 static int alaw2linear(unsigned char a_val)
51 t = a_val & QUANT_MASK;
52 seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
53 if(seg) t= (t + t + 1 + 32) << (seg + 2);
54 else t= (t + t + 1 ) << 3;
56 return ((a_val & SIGN_BIT) ? t : -t);
59 static int ulaw2linear(unsigned char u_val)
63 /* Complement to obtain normal u-law value. */
67 * Extract and bias the quantization bits. Then
68 * shift up by the segment number and subtract out the bias.
70 t = ((u_val & QUANT_MASK) << 3) + BIAS;
71 t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
73 return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS));
76 /* 16384 entries per table */
77 static uint8_t *linear_to_alaw = NULL;
78 static int linear_to_alaw_ref = 0;
80 static uint8_t *linear_to_ulaw = NULL;
81 static int linear_to_ulaw_ref = 0;
83 static void build_xlaw_table(uint8_t *linear_to_xlaw,
84 int (*xlaw2linear)(unsigned char),
92 v1 = xlaw2linear(i ^ mask);
93 v2 = xlaw2linear((i + 1) ^ mask);
94 v = (v1 + v2 + 4) >> 3;
99 linear_to_xlaw[8192 + j] = (i ^ mask);
101 linear_to_xlaw[8192 - j] = (i ^ (mask ^ 0x80));
104 linear_to_xlaw[0] = linear_to_xlaw[1];
107 static int pcm_encode_init(AVCodecContext *avctx)
109 avctx->frame_size = 1;
110 switch(avctx->codec->id) {
111 case CODEC_ID_PCM_ALAW:
112 if (linear_to_alaw_ref == 0) {
113 linear_to_alaw = av_malloc(16384);
116 build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5);
118 linear_to_alaw_ref++;
120 case CODEC_ID_PCM_MULAW:
121 if (linear_to_ulaw_ref == 0) {
122 linear_to_ulaw = av_malloc(16384);
125 build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff);
127 linear_to_ulaw_ref++;
133 switch(avctx->codec->id) {
134 case CODEC_ID_PCM_S32LE:
135 case CODEC_ID_PCM_S32BE:
136 case CODEC_ID_PCM_U32LE:
137 case CODEC_ID_PCM_U32BE:
138 avctx->block_align = 4 * avctx->channels;
140 case CODEC_ID_PCM_S24LE:
141 case CODEC_ID_PCM_S24BE:
142 case CODEC_ID_PCM_U24LE:
143 case CODEC_ID_PCM_U24BE:
144 case CODEC_ID_PCM_S24DAUD:
145 avctx->block_align = 3 * avctx->channels;
147 case CODEC_ID_PCM_S16LE:
148 case CODEC_ID_PCM_S16BE:
149 case CODEC_ID_PCM_U16LE:
150 case CODEC_ID_PCM_U16BE:
151 avctx->block_align = 2 * avctx->channels;
153 case CODEC_ID_PCM_S8:
154 case CODEC_ID_PCM_U8:
155 case CODEC_ID_PCM_MULAW:
156 case CODEC_ID_PCM_ALAW:
157 avctx->block_align = avctx->channels;
163 avctx->coded_frame= avcodec_alloc_frame();
164 avctx->coded_frame->key_frame= 1;
169 static int pcm_encode_close(AVCodecContext *avctx)
171 av_freep(&avctx->coded_frame);
173 switch(avctx->codec->id) {
174 case CODEC_ID_PCM_ALAW:
175 if (--linear_to_alaw_ref == 0)
176 av_free(linear_to_alaw);
178 case CODEC_ID_PCM_MULAW:
179 if (--linear_to_ulaw_ref == 0)
180 av_free(linear_to_ulaw);
183 /* nothing to free */
190 * \brief convert samples from 16 bit
191 * \param bps byte per sample for the destination format, must be >= 2
192 * \param le 0 for big-, 1 for little-endian
193 * \param us 0 for signed, 1 for unsigned output
194 * \param samples input samples
195 * \param dst output samples
196 * \param n number of samples in samples buffer.
198 static inline void encode_from16(int bps, int le, int us,
199 short **samples, uint8_t **dst, int n) {
201 memset(*dst, 0, n * bps);
202 if (le) *dst += bps - 2;
204 register int v = *(*samples)++;
210 if (le) *dst -= bps - 2;
213 static int pcm_encode_frame(AVCodecContext *avctx,
214 unsigned char *frame, int buf_size, void *data)
216 int n, sample_size, v;
220 switch(avctx->codec->id) {
221 case CODEC_ID_PCM_S32LE:
222 case CODEC_ID_PCM_S32BE:
223 case CODEC_ID_PCM_U32LE:
224 case CODEC_ID_PCM_U32BE:
227 case CODEC_ID_PCM_S24LE:
228 case CODEC_ID_PCM_S24BE:
229 case CODEC_ID_PCM_U24LE:
230 case CODEC_ID_PCM_U24BE:
231 case CODEC_ID_PCM_S24DAUD:
234 case CODEC_ID_PCM_S16LE:
235 case CODEC_ID_PCM_S16BE:
236 case CODEC_ID_PCM_U16LE:
237 case CODEC_ID_PCM_U16BE:
244 n = buf_size / sample_size;
248 switch(avctx->codec->id) {
249 case CODEC_ID_PCM_S32LE:
250 encode_from16(4, 1, 0, &samples, &dst, n);
252 case CODEC_ID_PCM_S32BE:
253 encode_from16(4, 0, 0, &samples, &dst, n);
255 case CODEC_ID_PCM_U32LE:
256 encode_from16(4, 1, 1, &samples, &dst, n);
258 case CODEC_ID_PCM_U32BE:
259 encode_from16(4, 0, 1, &samples, &dst, n);
261 case CODEC_ID_PCM_S24LE:
262 encode_from16(3, 1, 0, &samples, &dst, n);
264 case CODEC_ID_PCM_S24BE:
265 encode_from16(3, 0, 0, &samples, &dst, n);
267 case CODEC_ID_PCM_U24LE:
268 encode_from16(3, 1, 1, &samples, &dst, n);
270 case CODEC_ID_PCM_U24BE:
271 encode_from16(3, 0, 1, &samples, &dst, n);
273 case CODEC_ID_PCM_S24DAUD:
275 uint32_t tmp = ff_reverse[*samples >> 8] +
276 (ff_reverse[*samples & 0xff] << 8);
277 tmp <<= 4; // sync flags would go here
286 case CODEC_ID_PCM_S16LE:
294 case CODEC_ID_PCM_S16BE:
302 case CODEC_ID_PCM_U16LE:
311 case CODEC_ID_PCM_U16BE:
320 case CODEC_ID_PCM_S8:
327 case CODEC_ID_PCM_U8:
330 dst[0] = (v >> 8) + 128;
334 case CODEC_ID_PCM_ALAW:
337 dst[0] = linear_to_alaw[(v + 32768) >> 2];
341 case CODEC_ID_PCM_MULAW:
344 dst[0] = linear_to_ulaw[(v + 32768) >> 2];
351 //avctx->frame_size = (dst - frame) / (sample_size * avctx->channels);
356 typedef struct PCMDecode {
360 static int pcm_decode_init(AVCodecContext * avctx)
362 PCMDecode *s = avctx->priv_data;
365 switch(avctx->codec->id) {
366 case CODEC_ID_PCM_ALAW:
368 s->table[i] = alaw2linear(i);
370 case CODEC_ID_PCM_MULAW:
372 s->table[i] = ulaw2linear(i);
381 * \brief convert samples to 16 bit
382 * \param bps byte per sample for the source format, must be >= 2
383 * \param le 0 for big-, 1 for little-endian
384 * \param us 0 for signed, 1 for unsigned input
385 * \param src input samples
386 * \param samples output samples
387 * \param src_len number of bytes in src
389 static inline void decode_to16(int bps, int le, int us,
390 uint8_t **src, short **samples, int src_len)
392 register int n = src_len / bps;
393 if (le) *src += bps - 2;
395 *(*samples)++ = ((*src)[le] << 8 | (*src)[1 - le]) - (us?0x8000:0);
398 if (le) *src -= bps - 2;
401 static int pcm_decode_frame(AVCodecContext *avctx,
402 void *data, int *data_size,
403 uint8_t *buf, int buf_size)
405 PCMDecode *s = avctx->priv_data;
413 if(buf_size > AVCODEC_MAX_AUDIO_FRAME_SIZE/2)
414 buf_size = AVCODEC_MAX_AUDIO_FRAME_SIZE/2;
416 switch(avctx->codec->id) {
417 case CODEC_ID_PCM_S32LE:
418 decode_to16(4, 1, 0, &src, &samples, buf_size);
420 case CODEC_ID_PCM_S32BE:
421 decode_to16(4, 0, 0, &src, &samples, buf_size);
423 case CODEC_ID_PCM_U32LE:
424 decode_to16(4, 1, 1, &src, &samples, buf_size);
426 case CODEC_ID_PCM_U32BE:
427 decode_to16(4, 0, 1, &src, &samples, buf_size);
429 case CODEC_ID_PCM_S24LE:
430 decode_to16(3, 1, 0, &src, &samples, buf_size);
432 case CODEC_ID_PCM_S24BE:
433 decode_to16(3, 0, 0, &src, &samples, buf_size);
435 case CODEC_ID_PCM_U24LE:
436 decode_to16(3, 1, 1, &src, &samples, buf_size);
438 case CODEC_ID_PCM_U24BE:
439 decode_to16(3, 0, 1, &src, &samples, buf_size);
441 case CODEC_ID_PCM_S24DAUD:
444 uint32_t v = src[0] << 16 | src[1] << 8 | src[2];
445 v >>= 4; // sync flags are here
446 *samples++ = ff_reverse[(v >> 8) & 0xff] +
447 (ff_reverse[v & 0xff] << 8);
451 case CODEC_ID_PCM_S16LE:
454 *samples++ = src[0] | (src[1] << 8);
458 case CODEC_ID_PCM_S16BE:
461 *samples++ = (src[0] << 8) | src[1];
465 case CODEC_ID_PCM_U16LE:
468 *samples++ = (src[0] | (src[1] << 8)) - 0x8000;
472 case CODEC_ID_PCM_U16BE:
475 *samples++ = ((src[0] << 8) | src[1]) - 0x8000;
479 case CODEC_ID_PCM_S8:
482 *samples++ = src[0] << 8;
486 case CODEC_ID_PCM_U8:
489 *samples++ = ((int)src[0] - 128) << 8;
493 case CODEC_ID_PCM_ALAW:
494 case CODEC_ID_PCM_MULAW:
497 *samples++ = s->table[src[0]];
504 *data_size = (uint8_t *)samples - (uint8_t *)data;
508 #define PCM_CODEC(id, name) \
509 AVCodec name ## _encoder = { \
519 AVCodec name ## _decoder = { \
530 PCM_CODEC(CODEC_ID_PCM_S32LE, pcm_s32le);
531 PCM_CODEC(CODEC_ID_PCM_S32BE, pcm_s32be);
532 PCM_CODEC(CODEC_ID_PCM_U32LE, pcm_u32le);
533 PCM_CODEC(CODEC_ID_PCM_U32BE, pcm_u32be);
534 PCM_CODEC(CODEC_ID_PCM_S24LE, pcm_s24le);
535 PCM_CODEC(CODEC_ID_PCM_S24BE, pcm_s24be);
536 PCM_CODEC(CODEC_ID_PCM_U24LE, pcm_u24le);
537 PCM_CODEC(CODEC_ID_PCM_U24BE, pcm_u24be);
538 PCM_CODEC(CODEC_ID_PCM_S24DAUD, pcm_s24daud);
539 PCM_CODEC(CODEC_ID_PCM_S16LE, pcm_s16le);
540 PCM_CODEC(CODEC_ID_PCM_S16BE, pcm_s16be);
541 PCM_CODEC(CODEC_ID_PCM_U16LE, pcm_u16le);
542 PCM_CODEC(CODEC_ID_PCM_U16BE, pcm_u16be);
543 PCM_CODEC(CODEC_ID_PCM_S8, pcm_s8);
544 PCM_CODEC(CODEC_ID_PCM_U8, pcm_u8);
545 PCM_CODEC(CODEC_ID_PCM_ALAW, pcm_alaw);
546 PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw);