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libavcodec/pcm.c

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00001 /*
00002  * PCM codecs
00003  * Copyright (c) 2001 Fabrice Bellard
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #include "avcodec.h"
00028 #include "libavutil/common.h" /* for av_reverse */
00029 #include "bytestream.h"
00030 #include "pcm_tablegen.h"
00031 
00032 #define MAX_CHANNELS 64
00033 
00034 static av_cold int pcm_encode_init(AVCodecContext *avctx)
00035 {
00036     avctx->frame_size = 1;
00037     switch(avctx->codec->id) {
00038     case CODEC_ID_PCM_ALAW:
00039         pcm_alaw_tableinit();
00040         break;
00041     case CODEC_ID_PCM_MULAW:
00042         pcm_ulaw_tableinit();
00043         break;
00044     default:
00045         break;
00046     }
00047 
00048     avctx->bits_per_coded_sample = av_get_bits_per_sample(avctx->codec->id);
00049     avctx->block_align = avctx->channels * avctx->bits_per_coded_sample/8;
00050     avctx->coded_frame= avcodec_alloc_frame();
00051     avctx->coded_frame->key_frame= 1;
00052 
00053     return 0;
00054 }
00055 
00056 static av_cold int pcm_encode_close(AVCodecContext *avctx)
00057 {
00058     av_freep(&avctx->coded_frame);
00059 
00060     return 0;
00061 }
00062 
00073 #define ENCODE(type, endian, src, dst, n, shift, offset) \
00074     samples_##type = (type*)src; \
00075     for(;n>0;n--) { \
00076         register type v = (*samples_##type++ >> shift) + offset; \
00077         bytestream_put_##endian(&dst, v); \
00078     }
00079 
00080 static int pcm_encode_frame(AVCodecContext *avctx,
00081                             unsigned char *frame, int buf_size, void *data)
00082 {
00083     int n, sample_size, v;
00084     short *samples;
00085     unsigned char *dst;
00086     uint8_t *srcu8;
00087     int16_t *samples_int16_t;
00088     int32_t *samples_int32_t;
00089     int64_t *samples_int64_t;
00090     uint16_t *samples_uint16_t;
00091     uint32_t *samples_uint32_t;
00092 
00093     sample_size = av_get_bits_per_sample(avctx->codec->id)/8;
00094     n = buf_size / sample_size;
00095     samples = data;
00096     dst = frame;
00097 
00098     if (avctx->sample_fmt!=avctx->codec->sample_fmts[0]) {
00099         av_log(avctx, AV_LOG_ERROR, "invalid sample_fmt\n");
00100         return -1;
00101     }
00102 
00103     switch(avctx->codec->id) {
00104     case CODEC_ID_PCM_U32LE:
00105         ENCODE(uint32_t, le32, samples, dst, n, 0, 0x80000000)
00106         break;
00107     case CODEC_ID_PCM_U32BE:
00108         ENCODE(uint32_t, be32, samples, dst, n, 0, 0x80000000)
00109         break;
00110     case CODEC_ID_PCM_S24LE:
00111         ENCODE(int32_t, le24, samples, dst, n, 8, 0)
00112         break;
00113     case CODEC_ID_PCM_S24BE:
00114         ENCODE(int32_t, be24, samples, dst, n, 8, 0)
00115         break;
00116     case CODEC_ID_PCM_U24LE:
00117         ENCODE(uint32_t, le24, samples, dst, n, 8, 0x800000)
00118         break;
00119     case CODEC_ID_PCM_U24BE:
00120         ENCODE(uint32_t, be24, samples, dst, n, 8, 0x800000)
00121         break;
00122     case CODEC_ID_PCM_S24DAUD:
00123         for(;n>0;n--) {
00124             uint32_t tmp = av_reverse[(*samples >> 8) & 0xff] +
00125                            (av_reverse[*samples & 0xff] << 8);
00126             tmp <<= 4; // sync flags would go here
00127             bytestream_put_be24(&dst, tmp);
00128             samples++;
00129         }
00130         break;
00131     case CODEC_ID_PCM_U16LE:
00132         ENCODE(uint16_t, le16, samples, dst, n, 0, 0x8000)
00133         break;
00134     case CODEC_ID_PCM_U16BE:
00135         ENCODE(uint16_t, be16, samples, dst, n, 0, 0x8000)
00136         break;
00137     case CODEC_ID_PCM_S8:
00138         srcu8= data;
00139         for(;n>0;n--) {
00140             v = *srcu8++;
00141             *dst++ = v - 128;
00142         }
00143         break;
00144 #if HAVE_BIGENDIAN
00145     case CODEC_ID_PCM_F64LE:
00146         ENCODE(int64_t, le64, samples, dst, n, 0, 0)
00147         break;
00148     case CODEC_ID_PCM_S32LE:
00149     case CODEC_ID_PCM_F32LE:
00150         ENCODE(int32_t, le32, samples, dst, n, 0, 0)
00151         break;
00152     case CODEC_ID_PCM_S16LE:
00153         ENCODE(int16_t, le16, samples, dst, n, 0, 0)
00154         break;
00155     case CODEC_ID_PCM_F64BE:
00156     case CODEC_ID_PCM_F32BE:
00157     case CODEC_ID_PCM_S32BE:
00158     case CODEC_ID_PCM_S16BE:
00159 #else
00160     case CODEC_ID_PCM_F64BE:
00161         ENCODE(int64_t, be64, samples, dst, n, 0, 0)
00162         break;
00163     case CODEC_ID_PCM_F32BE:
00164     case CODEC_ID_PCM_S32BE:
00165         ENCODE(int32_t, be32, samples, dst, n, 0, 0)
00166         break;
00167     case CODEC_ID_PCM_S16BE:
00168         ENCODE(int16_t, be16, samples, dst, n, 0, 0)
00169         break;
00170     case CODEC_ID_PCM_F64LE:
00171     case CODEC_ID_PCM_F32LE:
00172     case CODEC_ID_PCM_S32LE:
00173     case CODEC_ID_PCM_S16LE:
00174 #endif /* HAVE_BIGENDIAN */
00175     case CODEC_ID_PCM_U8:
00176         memcpy(dst, samples, n*sample_size);
00177         dst += n*sample_size;
00178         break;
00179     case CODEC_ID_PCM_ZORK:
00180         for(;n>0;n--) {
00181             v= *samples++ >> 8;
00182             if(v<0)   v = -v;
00183             else      v+= 128;
00184             *dst++ = v;
00185         }
00186         break;
00187     case CODEC_ID_PCM_ALAW:
00188         for(;n>0;n--) {
00189             v = *samples++;
00190             *dst++ = linear_to_alaw[(v + 32768) >> 2];
00191         }
00192         break;
00193     case CODEC_ID_PCM_MULAW:
00194         for(;n>0;n--) {
00195             v = *samples++;
00196             *dst++ = linear_to_ulaw[(v + 32768) >> 2];
00197         }
00198         break;
00199     default:
00200         return -1;
00201     }
00202     //avctx->frame_size = (dst - frame) / (sample_size * avctx->channels);
00203 
00204     return dst - frame;
00205 }
00206 
00207 typedef struct PCMDecode {
00208     short table[256];
00209 } PCMDecode;
00210 
00211 static av_cold int pcm_decode_init(AVCodecContext * avctx)
00212 {
00213     PCMDecode *s = avctx->priv_data;
00214     int i;
00215 
00216     switch(avctx->codec->id) {
00217     case CODEC_ID_PCM_ALAW:
00218         for(i=0;i<256;i++)
00219             s->table[i] = alaw2linear(i);
00220         break;
00221     case CODEC_ID_PCM_MULAW:
00222         for(i=0;i<256;i++)
00223             s->table[i] = ulaw2linear(i);
00224         break;
00225     default:
00226         break;
00227     }
00228 
00229     avctx->sample_fmt = avctx->codec->sample_fmts[0];
00230     return 0;
00231 }
00232 
00243 #define DECODE(type, endian, src, dst, n, shift, offset) \
00244     dst_##type = (type*)dst; \
00245     for(;n>0;n--) { \
00246         register type v = bytestream_get_##endian(&src); \
00247         *dst_##type++ = (v - offset) << shift; \
00248     } \
00249     dst = (short*)dst_##type;
00250 
00251 static int pcm_decode_frame(AVCodecContext *avctx,
00252                             void *data, int *data_size,
00253                             AVPacket *avpkt)
00254 {
00255     const uint8_t *buf = avpkt->data;
00256     int buf_size = avpkt->size;
00257     PCMDecode *s = avctx->priv_data;
00258     int sample_size, c, n;
00259     short *samples;
00260     const uint8_t *src, *src8, *src2[MAX_CHANNELS];
00261     uint8_t *dstu8;
00262     int16_t *dst_int16_t;
00263     int32_t *dst_int32_t;
00264     int64_t *dst_int64_t;
00265     uint16_t *dst_uint16_t;
00266     uint32_t *dst_uint32_t;
00267 
00268     samples = data;
00269     src = buf;
00270 
00271     if (avctx->sample_fmt!=avctx->codec->sample_fmts[0]) {
00272         av_log(avctx, AV_LOG_ERROR, "invalid sample_fmt\n");
00273         return -1;
00274     }
00275 
00276     if(avctx->channels <= 0 || avctx->channels > MAX_CHANNELS){
00277         av_log(avctx, AV_LOG_ERROR, "PCM channels out of bounds\n");
00278         return -1;
00279     }
00280 
00281     sample_size = av_get_bits_per_sample(avctx->codec_id)/8;
00282 
00283     /* av_get_bits_per_sample returns 0 for CODEC_ID_PCM_DVD */
00284     if (CODEC_ID_PCM_DVD == avctx->codec_id)
00285         /* 2 samples are interleaved per block in PCM_DVD */
00286         sample_size = avctx->bits_per_coded_sample * 2 / 8;
00287 
00288     n = avctx->channels * sample_size;
00289 
00290     if(n && buf_size % n){
00291         if (buf_size < n) {
00292             av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
00293             return -1;
00294         }else
00295             buf_size -= buf_size % n;
00296     }
00297 
00298     buf_size= FFMIN(buf_size, *data_size/2);
00299     *data_size=0;
00300 
00301     n = buf_size/sample_size;
00302 
00303     switch(avctx->codec->id) {
00304     case CODEC_ID_PCM_U32LE:
00305         DECODE(uint32_t, le32, src, samples, n, 0, 0x80000000)
00306         break;
00307     case CODEC_ID_PCM_U32BE:
00308         DECODE(uint32_t, be32, src, samples, n, 0, 0x80000000)
00309         break;
00310     case CODEC_ID_PCM_S24LE:
00311         DECODE(int32_t, le24, src, samples, n, 8, 0)
00312         break;
00313     case CODEC_ID_PCM_S24BE:
00314         DECODE(int32_t, be24, src, samples, n, 8, 0)
00315         break;
00316     case CODEC_ID_PCM_U24LE:
00317         DECODE(uint32_t, le24, src, samples, n, 8, 0x800000)
00318         break;
00319     case CODEC_ID_PCM_U24BE:
00320         DECODE(uint32_t, be24, src, samples, n, 8, 0x800000)
00321         break;
00322     case CODEC_ID_PCM_S24DAUD:
00323         for(;n>0;n--) {
00324           uint32_t v = bytestream_get_be24(&src);
00325           v >>= 4; // sync flags are here
00326           *samples++ = av_reverse[(v >> 8) & 0xff] +
00327                        (av_reverse[v & 0xff] << 8);
00328         }
00329         break;
00330     case CODEC_ID_PCM_S16LE_PLANAR:
00331         n /= avctx->channels;
00332         for(c=0;c<avctx->channels;c++)
00333             src2[c] = &src[c*n*2];
00334         for(;n>0;n--)
00335             for(c=0;c<avctx->channels;c++)
00336                 *samples++ = bytestream_get_le16(&src2[c]);
00337         src = src2[avctx->channels-1];
00338         break;
00339     case CODEC_ID_PCM_U16LE:
00340         DECODE(uint16_t, le16, src, samples, n, 0, 0x8000)
00341         break;
00342     case CODEC_ID_PCM_U16BE:
00343         DECODE(uint16_t, be16, src, samples, n, 0, 0x8000)
00344         break;
00345     case CODEC_ID_PCM_S8:
00346         dstu8= (uint8_t*)samples;
00347         for(;n>0;n--) {
00348             *dstu8++ = *src++ + 128;
00349         }
00350         samples= (short*)dstu8;
00351         break;
00352 #if HAVE_BIGENDIAN
00353     case CODEC_ID_PCM_F64LE:
00354         DECODE(int64_t, le64, src, samples, n, 0, 0)
00355         break;
00356     case CODEC_ID_PCM_S32LE:
00357     case CODEC_ID_PCM_F32LE:
00358         DECODE(int32_t, le32, src, samples, n, 0, 0)
00359         break;
00360     case CODEC_ID_PCM_S16LE:
00361         DECODE(int16_t, le16, src, samples, n, 0, 0)
00362         break;
00363     case CODEC_ID_PCM_F64BE:
00364     case CODEC_ID_PCM_F32BE:
00365     case CODEC_ID_PCM_S32BE:
00366     case CODEC_ID_PCM_S16BE:
00367 #else
00368     case CODEC_ID_PCM_F64BE:
00369         DECODE(int64_t, be64, src, samples, n, 0, 0)
00370         break;
00371     case CODEC_ID_PCM_F32BE:
00372     case CODEC_ID_PCM_S32BE:
00373         DECODE(int32_t, be32, src, samples, n, 0, 0)
00374         break;
00375     case CODEC_ID_PCM_S16BE:
00376         DECODE(int16_t, be16, src, samples, n, 0, 0)
00377         break;
00378     case CODEC_ID_PCM_F64LE:
00379     case CODEC_ID_PCM_F32LE:
00380     case CODEC_ID_PCM_S32LE:
00381     case CODEC_ID_PCM_S16LE:
00382 #endif /* HAVE_BIGENDIAN */
00383     case CODEC_ID_PCM_U8:
00384         memcpy(samples, src, n*sample_size);
00385         src += n*sample_size;
00386         samples = (short*)((uint8_t*)data + n*sample_size);
00387         break;
00388     case CODEC_ID_PCM_ZORK:
00389         for(;n>0;n--) {
00390             int x= *src++;
00391             if(x&128) x-= 128;
00392             else      x = -x;
00393             *samples++ = x << 8;
00394         }
00395         break;
00396     case CODEC_ID_PCM_ALAW:
00397     case CODEC_ID_PCM_MULAW:
00398         for(;n>0;n--) {
00399             *samples++ = s->table[*src++];
00400         }
00401         break;
00402     case CODEC_ID_PCM_DVD:
00403         dst_int32_t = data;
00404         n /= avctx->channels;
00405         switch (avctx->bits_per_coded_sample) {
00406         case 20:
00407             while (n--) {
00408                 c = avctx->channels;
00409                 src8 = src + 4*c;
00410                 while (c--) {
00411                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8   &0xf0) << 8);
00412                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++ &0x0f) << 12);
00413                 }
00414                 src = src8;
00415             }
00416             break;
00417         case 24:
00418             while (n--) {
00419                 c = avctx->channels;
00420                 src8 = src + 4*c;
00421                 while (c--) {
00422                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
00423                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
00424                 }
00425                 src = src8;
00426             }
00427             break;
00428         default:
00429             av_log(avctx, AV_LOG_ERROR, "PCM DVD unsupported sample depth\n");
00430             return -1;
00431             break;
00432         }
00433         samples = (short *) dst_int32_t;
00434         break;
00435     default:
00436         return -1;
00437     }
00438     *data_size = (uint8_t *)samples - (uint8_t *)data;
00439     return src - buf;
00440 }
00441 
00442 #if CONFIG_ENCODERS
00443 #define PCM_ENCODER(id,sample_fmt_,name,long_name_) \
00444 AVCodec name ## _encoder = {                    \
00445     #name,                                      \
00446     AVMEDIA_TYPE_AUDIO,                         \
00447     id,                                         \
00448     0,                                          \
00449     pcm_encode_init,                            \
00450     pcm_encode_frame,                           \
00451     pcm_encode_close,                           \
00452     NULL,                                       \
00453     .sample_fmts = (const enum SampleFormat[]){sample_fmt_,SAMPLE_FMT_NONE}, \
00454     .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
00455 };
00456 #else
00457 #define PCM_ENCODER(id,sample_fmt_,name,long_name_)
00458 #endif
00459 
00460 #if CONFIG_DECODERS
00461 #define PCM_DECODER(id,sample_fmt_,name,long_name_)         \
00462 AVCodec name ## _decoder = {                    \
00463     #name,                                      \
00464     AVMEDIA_TYPE_AUDIO,                         \
00465     id,                                         \
00466     sizeof(PCMDecode),                          \
00467     pcm_decode_init,                            \
00468     NULL,                                       \
00469     NULL,                                       \
00470     pcm_decode_frame,                           \
00471     .sample_fmts = (const enum SampleFormat[]){sample_fmt_,SAMPLE_FMT_NONE}, \
00472     .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
00473 };
00474 #else
00475 #define PCM_DECODER(id,sample_fmt_,name,long_name_)
00476 #endif
00477 
00478 #define PCM_CODEC(id, sample_fmt_, name, long_name_)         \
00479     PCM_ENCODER(id,sample_fmt_,name,long_name_) PCM_DECODER(id,sample_fmt_,name,long_name_)
00480 
00481 /* Note: Do not forget to add new entries to the Makefile as well. */
00482 PCM_CODEC  (CODEC_ID_PCM_ALAW,  SAMPLE_FMT_S16, pcm_alaw, "PCM A-law");
00483 PCM_CODEC  (CODEC_ID_PCM_DVD,   SAMPLE_FMT_S32, pcm_dvd, "PCM signed 20|24-bit big-endian");
00484 PCM_CODEC  (CODEC_ID_PCM_F32BE, SAMPLE_FMT_FLT, pcm_f32be, "PCM 32-bit floating point big-endian");
00485 PCM_CODEC  (CODEC_ID_PCM_F32LE, SAMPLE_FMT_FLT, pcm_f32le, "PCM 32-bit floating point little-endian");
00486 PCM_CODEC  (CODEC_ID_PCM_F64BE, SAMPLE_FMT_DBL, pcm_f64be, "PCM 64-bit floating point big-endian");
00487 PCM_CODEC  (CODEC_ID_PCM_F64LE, SAMPLE_FMT_DBL, pcm_f64le, "PCM 64-bit floating point little-endian");
00488 PCM_CODEC  (CODEC_ID_PCM_MULAW, SAMPLE_FMT_S16, pcm_mulaw, "PCM mu-law");
00489 PCM_CODEC  (CODEC_ID_PCM_S8,    SAMPLE_FMT_U8,  pcm_s8, "PCM signed 8-bit");
00490 PCM_CODEC  (CODEC_ID_PCM_S16BE, SAMPLE_FMT_S16, pcm_s16be, "PCM signed 16-bit big-endian");
00491 PCM_CODEC  (CODEC_ID_PCM_S16LE, SAMPLE_FMT_S16, pcm_s16le, "PCM signed 16-bit little-endian");
00492 PCM_DECODER(CODEC_ID_PCM_S16LE_PLANAR, SAMPLE_FMT_S16, pcm_s16le_planar, "PCM 16-bit little-endian planar");
00493 PCM_CODEC  (CODEC_ID_PCM_S24BE, SAMPLE_FMT_S32, pcm_s24be, "PCM signed 24-bit big-endian");
00494 PCM_CODEC  (CODEC_ID_PCM_S24DAUD, SAMPLE_FMT_S16,  pcm_s24daud, "PCM D-Cinema audio signed 24-bit");
00495 PCM_CODEC  (CODEC_ID_PCM_S24LE, SAMPLE_FMT_S32, pcm_s24le, "PCM signed 24-bit little-endian");
00496 PCM_CODEC  (CODEC_ID_PCM_S32BE, SAMPLE_FMT_S32, pcm_s32be, "PCM signed 32-bit big-endian");
00497 PCM_CODEC  (CODEC_ID_PCM_S32LE, SAMPLE_FMT_S32, pcm_s32le, "PCM signed 32-bit little-endian");
00498 PCM_CODEC  (CODEC_ID_PCM_U8,    SAMPLE_FMT_U8,  pcm_u8, "PCM unsigned 8-bit");
00499 PCM_CODEC  (CODEC_ID_PCM_U16BE, SAMPLE_FMT_S16, pcm_u16be, "PCM unsigned 16-bit big-endian");
00500 PCM_CODEC  (CODEC_ID_PCM_U16LE, SAMPLE_FMT_S16, pcm_u16le, "PCM unsigned 16-bit little-endian");
00501 PCM_CODEC  (CODEC_ID_PCM_U24BE, SAMPLE_FMT_S32, pcm_u24be, "PCM unsigned 24-bit big-endian");
00502 PCM_CODEC  (CODEC_ID_PCM_U24LE, SAMPLE_FMT_S32, pcm_u24le, "PCM unsigned 24-bit little-endian");
00503 PCM_CODEC  (CODEC_ID_PCM_U32BE, SAMPLE_FMT_S32, pcm_u32be, "PCM unsigned 32-bit big-endian");
00504 PCM_CODEC  (CODEC_ID_PCM_U32LE, SAMPLE_FMT_S32, pcm_u32le, "PCM unsigned 32-bit little-endian");
00505 PCM_CODEC  (CODEC_ID_PCM_ZORK,  SAMPLE_FMT_S16, pcm_zork, "PCM Zork");

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