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Diffstat (limited to 'contrib/ffmpeg/libavcodec/pcm.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/pcm.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/pcm.c b/contrib/ffmpeg/libavcodec/pcm.c new file mode 100644 index 000000000..5570c01bd --- /dev/null +++ b/contrib/ffmpeg/libavcodec/pcm.c @@ -0,0 +1,526 @@ +/* + * PCM codecs + * Copyright (c) 2001 Fabrice Bellard. + * + * This file is part of FFmpeg. + * + * FFmpeg 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 2.1 of the License, or (at your option) any later version. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file pcm.c + * PCM codecs + */ + +#include "avcodec.h" +#include "bitstream.h" // for ff_reverse + +/* from g711.c by SUN microsystems (unrestricted use) */ + +#define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */ +#define QUANT_MASK (0xf) /* Quantization field mask. */ +#define NSEGS (8) /* Number of A-law segments. */ +#define SEG_SHIFT (4) /* Left shift for segment number. */ +#define SEG_MASK (0x70) /* Segment field mask. */ + +#define BIAS (0x84) /* Bias for linear code. */ + +/* + * alaw2linear() - Convert an A-law value to 16-bit linear PCM + * + */ +static int alaw2linear(unsigned char a_val) +{ + int t; + int seg; + + a_val ^= 0x55; + + t = a_val & QUANT_MASK; + seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT; + if(seg) t= (t + t + 1 + 32) << (seg + 2); + else t= (t + t + 1 ) << 3; + + return ((a_val & SIGN_BIT) ? t : -t); +} + +static int ulaw2linear(unsigned char u_val) +{ + int t; + + /* Complement to obtain normal u-law value. */ + u_val = ~u_val; + + /* + * Extract and bias the quantization bits. Then + * shift up by the segment number and subtract out the bias. + */ + t = ((u_val & QUANT_MASK) << 3) + BIAS; + t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT; + + return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS)); +} + +/* 16384 entries per table */ +static uint8_t linear_to_alaw[16384]; +static uint8_t linear_to_ulaw[16384]; + +static void build_xlaw_table(uint8_t *linear_to_xlaw, + int (*xlaw2linear)(unsigned char), + int mask) +{ + int i, j, v, v1, v2; + + j = 0; + for(i=0;i<128;i++) { + if (i != 127) { + v1 = xlaw2linear(i ^ mask); + v2 = xlaw2linear((i + 1) ^ mask); + v = (v1 + v2 + 4) >> 3; + } else { + v = 8192; + } + for(;j<v;j++) { + linear_to_xlaw[8192 + j] = (i ^ mask); + if (j > 0) + linear_to_xlaw[8192 - j] = (i ^ (mask ^ 0x80)); + } + } + linear_to_xlaw[0] = linear_to_xlaw[1]; +} + +static int pcm_encode_init(AVCodecContext *avctx) +{ + avctx->frame_size = 1; + switch(avctx->codec->id) { + case CODEC_ID_PCM_ALAW: + build_xlaw_table(linear_to_alaw, alaw2linear, 0xd5); + break; + case CODEC_ID_PCM_MULAW: + build_xlaw_table(linear_to_ulaw, ulaw2linear, 0xff); + break; + default: + break; + } + + switch(avctx->codec->id) { + case CODEC_ID_PCM_S32LE: + case CODEC_ID_PCM_S32BE: + case CODEC_ID_PCM_U32LE: + case CODEC_ID_PCM_U32BE: + avctx->block_align = 4 * avctx->channels; + break; + case CODEC_ID_PCM_S24LE: + case CODEC_ID_PCM_S24BE: + case CODEC_ID_PCM_U24LE: + case CODEC_ID_PCM_U24BE: + case CODEC_ID_PCM_S24DAUD: + avctx->block_align = 3 * avctx->channels; + break; + case CODEC_ID_PCM_S16LE: + case CODEC_ID_PCM_S16BE: + case CODEC_ID_PCM_U16LE: + case CODEC_ID_PCM_U16BE: + avctx->block_align = 2 * avctx->channels; + break; + case CODEC_ID_PCM_S8: + case CODEC_ID_PCM_U8: + case CODEC_ID_PCM_MULAW: + case CODEC_ID_PCM_ALAW: + avctx->block_align = avctx->channels; + break; + default: + break; + } + + avctx->coded_frame= avcodec_alloc_frame(); + avctx->coded_frame->key_frame= 1; + + return 0; +} + +static int pcm_encode_close(AVCodecContext *avctx) +{ + av_freep(&avctx->coded_frame); + + return 0; +} + +/** + * \brief convert samples from 16 bit + * \param bps byte per sample for the destination format, must be >= 2 + * \param le 0 for big-, 1 for little-endian + * \param us 0 for signed, 1 for unsigned output + * \param samples input samples + * \param dst output samples + * \param n number of samples in samples buffer. + */ +static inline void encode_from16(int bps, int le, int us, + short **samples, uint8_t **dst, int n) { + if (bps > 2) + memset(*dst, 0, n * bps); + if (le) *dst += bps - 2; + for(;n>0;n--) { + register int v = *(*samples)++; + if (us) v += 0x8000; + (*dst)[le] = v >> 8; + (*dst)[1 - le] = v; + *dst += bps; + } + if (le) *dst -= bps - 2; +} + +static int pcm_encode_frame(AVCodecContext *avctx, + unsigned char *frame, int buf_size, void *data) +{ + int n, sample_size, v; + short *samples; + unsigned char *dst; + + switch(avctx->codec->id) { + case CODEC_ID_PCM_S32LE: + case CODEC_ID_PCM_S32BE: + case CODEC_ID_PCM_U32LE: + case CODEC_ID_PCM_U32BE: + sample_size = 4; + break; + case CODEC_ID_PCM_S24LE: + case CODEC_ID_PCM_S24BE: + case CODEC_ID_PCM_U24LE: + case CODEC_ID_PCM_U24BE: + case CODEC_ID_PCM_S24DAUD: + sample_size = 3; + break; + case CODEC_ID_PCM_S16LE: + case CODEC_ID_PCM_S16BE: + case CODEC_ID_PCM_U16LE: + case CODEC_ID_PCM_U16BE: + sample_size = 2; + break; + default: + sample_size = 1; + break; + } + n = buf_size / sample_size; + samples = data; + dst = frame; + + switch(avctx->codec->id) { + case CODEC_ID_PCM_S32LE: + encode_from16(4, 1, 0, &samples, &dst, n); + break; + case CODEC_ID_PCM_S32BE: + encode_from16(4, 0, 0, &samples, &dst, n); + break; + case CODEC_ID_PCM_U32LE: + encode_from16(4, 1, 1, &samples, &dst, n); + break; + case CODEC_ID_PCM_U32BE: + encode_from16(4, 0, 1, &samples, &dst, n); + break; + case CODEC_ID_PCM_S24LE: + encode_from16(3, 1, 0, &samples, &dst, n); + break; + case CODEC_ID_PCM_S24BE: + encode_from16(3, 0, 0, &samples, &dst, n); + break; + case CODEC_ID_PCM_U24LE: + encode_from16(3, 1, 1, &samples, &dst, n); + break; + case CODEC_ID_PCM_U24BE: + encode_from16(3, 0, 1, &samples, &dst, n); + break; + case CODEC_ID_PCM_S24DAUD: + for(;n>0;n--) { + uint32_t tmp = ff_reverse[*samples >> 8] + + (ff_reverse[*samples & 0xff] << 8); + tmp <<= 4; // sync flags would go here + dst[2] = tmp & 0xff; + tmp >>= 8; + dst[1] = tmp & 0xff; + dst[0] = tmp >> 8; + samples++; + dst += 3; + } + break; + case CODEC_ID_PCM_S16LE: + for(;n>0;n--) { + v = *samples++; + dst[0] = v & 0xff; + dst[1] = v >> 8; + dst += 2; + } + break; + case CODEC_ID_PCM_S16BE: + for(;n>0;n--) { + v = *samples++; + dst[0] = v >> 8; + dst[1] = v; + dst += 2; + } + break; + case CODEC_ID_PCM_U16LE: + for(;n>0;n--) { + v = *samples++; + v += 0x8000; + dst[0] = v & 0xff; + dst[1] = v >> 8; + dst += 2; + } + break; + case CODEC_ID_PCM_U16BE: + for(;n>0;n--) { + v = *samples++; + v += 0x8000; + dst[0] = v >> 8; + dst[1] = v; + dst += 2; + } + break; + case CODEC_ID_PCM_S8: + for(;n>0;n--) { + v = *samples++; + dst[0] = v >> 8; + dst++; + } + break; + case CODEC_ID_PCM_U8: + for(;n>0;n--) { + v = *samples++; + dst[0] = (v >> 8) + 128; + dst++; + } + break; + case CODEC_ID_PCM_ALAW: + for(;n>0;n--) { + v = *samples++; + dst[0] = linear_to_alaw[(v + 32768) >> 2]; + dst++; + } + break; + case CODEC_ID_PCM_MULAW: + for(;n>0;n--) { + v = *samples++; + dst[0] = linear_to_ulaw[(v + 32768) >> 2]; + dst++; + } + break; + default: + return -1; + } + //avctx->frame_size = (dst - frame) / (sample_size * avctx->channels); + + return dst - frame; +} + +typedef struct PCMDecode { + short table[256]; +} PCMDecode; + +static int pcm_decode_init(AVCodecContext * avctx) +{ + PCMDecode *s = avctx->priv_data; + int i; + + switch(avctx->codec->id) { + case CODEC_ID_PCM_ALAW: + for(i=0;i<256;i++) + s->table[i] = alaw2linear(i); + break; + case CODEC_ID_PCM_MULAW: + for(i=0;i<256;i++) + s->table[i] = ulaw2linear(i); + break; + default: + break; + } + return 0; +} + +/** + * \brief convert samples to 16 bit + * \param bps byte per sample for the source format, must be >= 2 + * \param le 0 for big-, 1 for little-endian + * \param us 0 for signed, 1 for unsigned input + * \param src input samples + * \param samples output samples + * \param src_len number of bytes in src + */ +static inline void decode_to16(int bps, int le, int us, + uint8_t **src, short **samples, int src_len) +{ + register int n = src_len / bps; + if (le) *src += bps - 2; + for(;n>0;n--) { + *(*samples)++ = ((*src)[le] << 8 | (*src)[1 - le]) - (us?0x8000:0); + *src += bps; + } + if (le) *src -= bps - 2; +} + +static int pcm_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + PCMDecode *s = avctx->priv_data; + int n; + short *samples; + uint8_t *src; + + samples = data; + src = buf; + + n= av_get_bits_per_sample(avctx->codec_id)/8; + if(n && buf_size % n){ + av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n"); + return -1; + } + + buf_size= FFMIN(buf_size, *data_size/2); + *data_size=0; + + switch(avctx->codec->id) { + case CODEC_ID_PCM_S32LE: + decode_to16(4, 1, 0, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_S32BE: + decode_to16(4, 0, 0, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_U32LE: + decode_to16(4, 1, 1, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_U32BE: + decode_to16(4, 0, 1, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_S24LE: + decode_to16(3, 1, 0, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_S24BE: + decode_to16(3, 0, 0, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_U24LE: + decode_to16(3, 1, 1, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_U24BE: + decode_to16(3, 0, 1, &src, &samples, buf_size); + break; + case CODEC_ID_PCM_S24DAUD: + n = buf_size / 3; + for(;n>0;n--) { + uint32_t v = src[0] << 16 | src[1] << 8 | src[2]; + v >>= 4; // sync flags are here + *samples++ = ff_reverse[(v >> 8) & 0xff] + + (ff_reverse[v & 0xff] << 8); + src += 3; + } + break; + case CODEC_ID_PCM_S16LE: + n = buf_size >> 1; + for(;n>0;n--) { + *samples++ = src[0] | (src[1] << 8); + src += 2; + } + break; + case CODEC_ID_PCM_S16BE: + n = buf_size >> 1; + for(;n>0;n--) { + *samples++ = (src[0] << 8) | src[1]; + src += 2; + } + break; + case CODEC_ID_PCM_U16LE: + n = buf_size >> 1; + for(;n>0;n--) { + *samples++ = (src[0] | (src[1] << 8)) - 0x8000; + src += 2; + } + break; + case CODEC_ID_PCM_U16BE: + n = buf_size >> 1; + for(;n>0;n--) { + *samples++ = ((src[0] << 8) | src[1]) - 0x8000; + src += 2; + } + break; + case CODEC_ID_PCM_S8: + n = buf_size; + for(;n>0;n--) { + *samples++ = src[0] << 8; + src++; + } + break; + case CODEC_ID_PCM_U8: + n = buf_size; + for(;n>0;n--) { + *samples++ = ((int)src[0] - 128) << 8; + src++; + } + break; + case CODEC_ID_PCM_ALAW: + case CODEC_ID_PCM_MULAW: + n = buf_size; + for(;n>0;n--) { + *samples++ = s->table[src[0]]; + src++; + } + break; + default: + return -1; + } + *data_size = (uint8_t *)samples - (uint8_t *)data; + return src - buf; +} + +#define PCM_CODEC(id, name) \ +AVCodec name ## _encoder = { \ + #name, \ + CODEC_TYPE_AUDIO, \ + id, \ + 0, \ + pcm_encode_init, \ + pcm_encode_frame, \ + pcm_encode_close, \ + NULL, \ +}; \ +AVCodec name ## _decoder = { \ + #name, \ + CODEC_TYPE_AUDIO, \ + id, \ + sizeof(PCMDecode), \ + pcm_decode_init, \ + NULL, \ + NULL, \ + pcm_decode_frame, \ +} + +PCM_CODEC(CODEC_ID_PCM_S32LE, pcm_s32le); +PCM_CODEC(CODEC_ID_PCM_S32BE, pcm_s32be); +PCM_CODEC(CODEC_ID_PCM_U32LE, pcm_u32le); +PCM_CODEC(CODEC_ID_PCM_U32BE, pcm_u32be); +PCM_CODEC(CODEC_ID_PCM_S24LE, pcm_s24le); +PCM_CODEC(CODEC_ID_PCM_S24BE, pcm_s24be); +PCM_CODEC(CODEC_ID_PCM_U24LE, pcm_u24le); +PCM_CODEC(CODEC_ID_PCM_U24BE, pcm_u24be); +PCM_CODEC(CODEC_ID_PCM_S24DAUD, pcm_s24daud); +PCM_CODEC(CODEC_ID_PCM_S16LE, pcm_s16le); +PCM_CODEC(CODEC_ID_PCM_S16BE, pcm_s16be); +PCM_CODEC(CODEC_ID_PCM_U16LE, pcm_u16le); +PCM_CODEC(CODEC_ID_PCM_U16BE, pcm_u16be); +PCM_CODEC(CODEC_ID_PCM_S8, pcm_s8); +PCM_CODEC(CODEC_ID_PCM_U8, pcm_u8); +PCM_CODEC(CODEC_ID_PCM_ALAW, pcm_alaw); +PCM_CODEC(CODEC_ID_PCM_MULAW, pcm_mulaw); + +#undef PCM_CODEC |