FFmpeg: libavcodec/pcm.c Source File

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 "libavutil/common.h" /* for av_reverse */
00028 #include "avcodec.h"
00029 #include "bytestream.h"
00030 #include "internal.h"
00031 #include "pcm_tablegen.h"
00032 
00033 #define MAX_CHANNELS 64
00034 
00035 static av_cold int pcm_encode_init(AVCodecContext *avctx)
00036 {
00037     avctx->frame_size = 0;
00038     switch (avctx->codec->id) {
00039     case CODEC_ID_PCM_ALAW:
00040         pcm_alaw_tableinit();
00041         break;
00042     case CODEC_ID_PCM_MULAW:
00043         pcm_ulaw_tableinit();
00044         break;
00045     default:
00046         break;
00047     }
00048 
00049     avctx->bits_per_coded_sample = av_get_bits_per_sample(avctx->codec->id);
00050     avctx->block_align           = avctx->channels * avctx->bits_per_coded_sample / 8;
00051     avctx->bit_rate              = avctx->block_align * avctx->sample_rate * 8;
00052     avctx->coded_frame           = avcodec_alloc_frame();
00053     if (!avctx->coded_frame)
00054         return AVERROR(ENOMEM);
00055 
00056     return 0;
00057 }
00058 
00059 static av_cold int pcm_encode_close(AVCodecContext *avctx)
00060 {
00061     av_freep(&avctx->coded_frame);
00062 
00063     return 0;
00064 }
00065 
00076 #define ENCODE(type, endian, src, dst, n, shift, offset)                \
00077     samples_ ## type = (const type *) src;                              \
00078     for (; n > 0; n--) {                                                \
00079         register type v = (*samples_ ## type++ >> shift) + offset;      \
00080         bytestream_put_ ## endian(&dst, v);                             \
00081     }
00082 
00083 static int pcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
00084                             const AVFrame *frame, int *got_packet_ptr)
00085 {
00086     int n, sample_size, v, ret;
00087     const short *samples;
00088     unsigned char *dst;
00089     const uint8_t *srcu8;
00090     const int16_t *samples_int16_t;
00091     const int32_t *samples_int32_t;
00092     const int64_t *samples_int64_t;
00093     const uint16_t *samples_uint16_t;
00094     const uint32_t *samples_uint32_t;
00095 
00096     sample_size = av_get_bits_per_sample(avctx->codec->id) / 8;
00097     n           = frame->nb_samples * avctx->channels;
00098     samples     = (const short *)frame->data[0];
00099 
00100     if ((ret = ff_alloc_packet2(avctx, avpkt, n * sample_size)))
00101         return ret;
00102     dst = avpkt->data;
00103 
00104     switch (avctx->codec->id) {
00105     case CODEC_ID_PCM_U32LE:
00106         ENCODE(uint32_t, le32, samples, dst, n, 0, 0x80000000)
00107         break;
00108     case CODEC_ID_PCM_U32BE:
00109         ENCODE(uint32_t, be32, samples, dst, n, 0, 0x80000000)
00110         break;
00111     case CODEC_ID_PCM_S24LE:
00112         ENCODE(int32_t, le24, samples, dst, n, 8, 0)
00113         break;
00114     case CODEC_ID_PCM_S24BE:
00115         ENCODE(int32_t, be24, samples, dst, n, 8, 0)
00116         break;
00117     case CODEC_ID_PCM_U24LE:
00118         ENCODE(uint32_t, le24, samples, dst, n, 8, 0x800000)
00119         break;
00120     case CODEC_ID_PCM_U24BE:
00121         ENCODE(uint32_t, be24, samples, dst, n, 8, 0x800000)
00122         break;
00123     case CODEC_ID_PCM_S24DAUD:
00124         for (; n > 0; n--) {
00125             uint32_t tmp = av_reverse[(*samples >> 8) & 0xff] +
00126                            (av_reverse[*samples & 0xff] << 8);
00127             tmp <<= 4; // sync flags would go here
00128             bytestream_put_be24(&dst, tmp);
00129             samples++;
00130         }
00131         break;
00132     case CODEC_ID_PCM_U16LE:
00133         ENCODE(uint16_t, le16, samples, dst, n, 0, 0x8000)
00134         break;
00135     case CODEC_ID_PCM_U16BE:
00136         ENCODE(uint16_t, be16, samples, dst, n, 0, 0x8000)
00137         break;
00138     case CODEC_ID_PCM_S8:
00139         srcu8 = frame->data[0];
00140         for (; n > 0; n--) {
00141             v      = *srcu8++;
00142             *dst++ = v - 128;
00143         }
00144         break;
00145 #if HAVE_BIGENDIAN
00146     case CODEC_ID_PCM_F64LE:
00147         ENCODE(int64_t, le64, samples, dst, n, 0, 0)
00148         break;
00149     case CODEC_ID_PCM_S32LE:
00150     case CODEC_ID_PCM_F32LE:
00151         ENCODE(int32_t, le32, samples, dst, n, 0, 0)
00152         break;
00153     case CODEC_ID_PCM_S16LE:
00154         ENCODE(int16_t, le16, samples, dst, n, 0, 0)
00155         break;
00156     case CODEC_ID_PCM_F64BE:
00157     case CODEC_ID_PCM_F32BE:
00158     case CODEC_ID_PCM_S32BE:
00159     case CODEC_ID_PCM_S16BE:
00160 #else
00161     case CODEC_ID_PCM_F64BE:
00162         ENCODE(int64_t, be64, samples, dst, n, 0, 0)
00163         break;
00164     case CODEC_ID_PCM_F32BE:
00165     case CODEC_ID_PCM_S32BE:
00166         ENCODE(int32_t, be32, samples, dst, n, 0, 0)
00167         break;
00168     case CODEC_ID_PCM_S16BE:
00169         ENCODE(int16_t, be16, samples, dst, n, 0, 0)
00170         break;
00171     case CODEC_ID_PCM_F64LE:
00172     case CODEC_ID_PCM_F32LE:
00173     case CODEC_ID_PCM_S32LE:
00174     case CODEC_ID_PCM_S16LE:
00175 #endif /* HAVE_BIGENDIAN */
00176     case CODEC_ID_PCM_U8:
00177         memcpy(dst, samples, n * sample_size);
00178         dst += n * sample_size;
00179         break;
00180     case CODEC_ID_PCM_ALAW:
00181         for (; n > 0; n--) {
00182             v      = *samples++;
00183             *dst++ = linear_to_alaw[(v + 32768) >> 2];
00184         }
00185         break;
00186     case CODEC_ID_PCM_MULAW:
00187         for (; n > 0; n--) {
00188             v      = *samples++;
00189             *dst++ = linear_to_ulaw[(v + 32768) >> 2];
00190         }
00191         break;
00192     default:
00193         return -1;
00194     }
00195 
00196     *got_packet_ptr = 1;
00197     return 0;
00198 }
00199 
00200 typedef struct PCMDecode {
00201     AVFrame frame;
00202     short   table[256];
00203 } PCMDecode;
00204 
00205 static av_cold int pcm_decode_init(AVCodecContext *avctx)
00206 {
00207     PCMDecode *s = avctx->priv_data;
00208     int i;
00209 
00210     if (avctx->channels <= 0 || avctx->channels > MAX_CHANNELS) {
00211         av_log(avctx, AV_LOG_ERROR, "PCM channels out of bounds\n");
00212         return AVERROR(EINVAL);
00213     }
00214 
00215     switch (avctx->codec->id) {
00216     case CODEC_ID_PCM_ALAW:
00217         for (i = 0; i < 256; i++)
00218             s->table[i] = alaw2linear(i);
00219         break;
00220     case CODEC_ID_PCM_MULAW:
00221         for (i = 0; i < 256; i++)
00222             s->table[i] = ulaw2linear(i);
00223         break;
00224     default:
00225         break;
00226     }
00227 
00228     avctx->sample_fmt = avctx->codec->sample_fmts[0];
00229 
00230     if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
00231         avctx->bits_per_raw_sample = av_get_bits_per_sample(avctx->codec->id);
00232 
00233     avcodec_get_frame_defaults(&s->frame);
00234     avctx->coded_frame = &s->frame;
00235 
00236     return 0;
00237 }
00238 
00249 #define DECODE(size, endian, src, dst, n, shift, offset)                \
00250     for (; n > 0; n--) {                                                \
00251         uint ## size ## _t v = bytestream_get_ ## endian(&src);         \
00252         AV_WN ## size ## A(dst, (v - offset) << shift);                 \
00253         dst += size / 8;                                                \
00254     }
00255 
00256 static int pcm_decode_frame(AVCodecContext *avctx, void *data,
00257                             int *got_frame_ptr, AVPacket *avpkt)
00258 {
00259     const uint8_t *src = avpkt->data;
00260     int buf_size       = avpkt->size;
00261     PCMDecode *s       = avctx->priv_data;
00262     int sample_size, c, n, ret, samples_per_block;
00263     uint8_t *samples;
00264     int32_t *dst_int32_t;
00265 
00266     sample_size = av_get_bits_per_sample(avctx->codec_id) / 8;
00267 
00268     /* av_get_bits_per_sample returns 0 for CODEC_ID_PCM_DVD */
00269     samples_per_block = 1;
00270     if (CODEC_ID_PCM_DVD == avctx->codec_id) {
00271         if (avctx->bits_per_coded_sample != 20 &&
00272             avctx->bits_per_coded_sample != 24) {
00273             av_log(avctx, AV_LOG_ERROR,
00274                    "PCM DVD unsupported sample depth %i\n",
00275                    avctx->bits_per_coded_sample);
00276             return AVERROR(EINVAL);
00277         }
00278         /* 2 samples are interleaved per block in PCM_DVD */
00279         samples_per_block = 2;
00280         sample_size       = avctx->bits_per_coded_sample * 2 / 8;
00281     } else if (avctx->codec_id == CODEC_ID_PCM_LXF) {
00282         /* we process 40-bit blocks per channel for LXF */
00283         samples_per_block = 2;
00284         sample_size       = 5;
00285     }
00286 
00287     if (sample_size == 0) {
00288         av_log(avctx, AV_LOG_ERROR, "Invalid sample_size\n");
00289         return AVERROR(EINVAL);
00290     }
00291 
00292     n = avctx->channels * sample_size;
00293 
00294     if (n && buf_size % n) {
00295         if (buf_size < n) {
00296             av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n");
00297             return -1;
00298         } else
00299             buf_size -= buf_size % n;
00300     }
00301 
00302     n = buf_size / sample_size;
00303 
00304     /* get output buffer */
00305     s->frame.nb_samples = n * samples_per_block / avctx->channels;
00306     if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
00307         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00308         return ret;
00309     }
00310     samples = s->frame.data[0];
00311 
00312     switch (avctx->codec->id) {
00313     case CODEC_ID_PCM_U32LE:
00314         DECODE(32, le32, src, samples, n, 0, 0x80000000)
00315         break;
00316     case CODEC_ID_PCM_U32BE:
00317         DECODE(32, be32, src, samples, n, 0, 0x80000000)
00318         break;
00319     case CODEC_ID_PCM_S24LE:
00320         DECODE(32, le24, src, samples, n, 8, 0)
00321         break;
00322     case CODEC_ID_PCM_S24BE:
00323         DECODE(32, be24, src, samples, n, 8, 0)
00324         break;
00325     case CODEC_ID_PCM_U24LE:
00326         DECODE(32, le24, src, samples, n, 8, 0x800000)
00327         break;
00328     case CODEC_ID_PCM_U24BE:
00329         DECODE(32, be24, src, samples, n, 8, 0x800000)
00330         break;
00331     case CODEC_ID_PCM_S24DAUD:
00332         for (; n > 0; n--) {
00333             uint32_t v = bytestream_get_be24(&src);
00334             v >>= 4; // sync flags are here
00335             AV_WN16A(samples, av_reverse[(v >> 8) & 0xff] +
00336                              (av_reverse[v        & 0xff] << 8));
00337             samples += 2;
00338         }
00339         break;
00340     case CODEC_ID_PCM_S16LE_PLANAR:
00341     {
00342         int i;
00343         n /= avctx->channels;
00344         for (c = 0; c < avctx->channels; c++) {
00345             samples = s->frame.data[c];
00346             for (i = n; i > 0; i--) {
00347                 AV_WN16A(samples, bytestream_get_le16(&src));
00348                 samples += 2;
00349             }
00350         }
00351         break;
00352     }
00353     case CODEC_ID_PCM_U16LE:
00354         DECODE(16, le16, src, samples, n, 0, 0x8000)
00355         break;
00356     case CODEC_ID_PCM_U16BE:
00357         DECODE(16, be16, src, samples, n, 0, 0x8000)
00358         break;
00359     case CODEC_ID_PCM_S8:
00360         for (; n > 0; n--)
00361             *samples++ = *src++ + 128;
00362         break;
00363 #if HAVE_BIGENDIAN
00364     case CODEC_ID_PCM_F64LE:
00365         DECODE(64, le64, src, samples, n, 0, 0)
00366         break;
00367     case CODEC_ID_PCM_S32LE:
00368     case CODEC_ID_PCM_F32LE:
00369         DECODE(32, le32, src, samples, n, 0, 0)
00370         break;
00371     case CODEC_ID_PCM_S16LE:
00372         DECODE(16, le16, src, samples, n, 0, 0)
00373         break;
00374     case CODEC_ID_PCM_F64BE:
00375     case CODEC_ID_PCM_F32BE:
00376     case CODEC_ID_PCM_S32BE:
00377     case CODEC_ID_PCM_S16BE:
00378 #else
00379     case CODEC_ID_PCM_F64BE:
00380         DECODE(64, be64, src, samples, n, 0, 0)
00381         break;
00382     case CODEC_ID_PCM_F32BE:
00383     case CODEC_ID_PCM_S32BE:
00384         DECODE(32, be32, src, samples, n, 0, 0)
00385         break;
00386     case CODEC_ID_PCM_S16BE:
00387         DECODE(16, be16, src, samples, n, 0, 0)
00388         break;
00389     case CODEC_ID_PCM_F64LE:
00390     case CODEC_ID_PCM_F32LE:
00391     case CODEC_ID_PCM_S32LE:
00392     case CODEC_ID_PCM_S16LE:
00393 #endif /* HAVE_BIGENDIAN */
00394     case CODEC_ID_PCM_U8:
00395         memcpy(samples, src, n * sample_size);
00396         break;
00397     case CODEC_ID_PCM_ZORK:
00398         for (; n > 0; n--) {
00399             int v = *src++;
00400             if (v < 128)
00401                 v = 128 - v;
00402             *samples++ = v;
00403         }
00404         break;
00405     case CODEC_ID_PCM_ALAW:
00406     case CODEC_ID_PCM_MULAW:
00407         for (; n > 0; n--) {
00408             AV_WN16A(samples, s->table[*src++]);
00409             samples += 2;
00410         }
00411         break;
00412     case CODEC_ID_PCM_DVD:
00413     {
00414         const uint8_t *src8;
00415         dst_int32_t = (int32_t *)s->frame.data[0];
00416         n /= avctx->channels;
00417         switch (avctx->bits_per_coded_sample) {
00418         case 20:
00419             while (n--) {
00420                 c    = avctx->channels;
00421                 src8 = src + 4 * c;
00422                 while (c--) {
00423                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8   & 0xf0) <<  8);
00424                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++ & 0x0f) << 12);
00425                 }
00426                 src = src8;
00427             }
00428             break;
00429         case 24:
00430             while (n--) {
00431                 c    = avctx->channels;
00432                 src8 = src + 4 * c;
00433                 while (c--) {
00434                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
00435                     *dst_int32_t++ = (bytestream_get_be16(&src) << 16) + ((*src8++) << 8);
00436                 }
00437                 src = src8;
00438             }
00439             break;
00440         }
00441         break;
00442     }
00443     case CODEC_ID_PCM_LXF:
00444     {
00445         int i;
00446         n /= avctx->channels;
00447         //unpack
00448         for (c = 0; c < avctx->channels; c++) {
00449             dst_int32_t = (int32_t *)s->frame.data[c];
00450             for (i = 0; i < n; i++) {
00451                 //extract low 20 bits and expand to 32 bits
00452                 *dst_int32_t++ = (src[2] << 28) |
00453                                  (src[1] << 20) |
00454                                  (src[0] << 12) |
00455                                  ((src[2] & 0xF) << 8) |
00456                                  src[1];
00457                 //extract high 20 bits and expand to 32 bits
00458                 *dst_int32_t++ = (src[4] << 24) |
00459                                  (src[3] << 16) |
00460                                  ((src[2] & 0xF0) << 8) |
00461                                  (src[4] << 4) |
00462                                  (src[3] >> 4);
00463                 src += 5;
00464             }
00465         }
00466         break;
00467     }
00468     default:
00469         return -1;
00470     }
00471 
00472     *got_frame_ptr   = 1;
00473     *(AVFrame *)data = s->frame;
00474 
00475     return buf_size;
00476 }
00477 
00478 #if CONFIG_ENCODERS
00479 #define PCM_ENCODER(id_, sample_fmt_, name_, long_name_)                    \
00480 AVCodec ff_ ## name_ ## _encoder = {                                        \
00481     .name         = #name_,                                                 \
00482     .type         = AVMEDIA_TYPE_AUDIO,                                     \
00483     .id           = id_,                                                    \
00484     .init         = pcm_encode_init,                                        \
00485     .encode2      = pcm_encode_frame,                                       \
00486     .close        = pcm_encode_close,                                       \
00487     .capabilities = CODEC_CAP_VARIABLE_FRAME_SIZE,                          \
00488     .sample_fmts  = (const enum AVSampleFormat[]){ sample_fmt_,             \
00489                                                    AV_SAMPLE_FMT_NONE },    \
00490     .long_name    = NULL_IF_CONFIG_SMALL(long_name_),                       \
00491 }
00492 #else
00493 #define PCM_ENCODER(id, sample_fmt_, name, long_name_)
00494 #endif
00495 
00496 #if CONFIG_DECODERS
00497 #define PCM_DECODER(id_, sample_fmt_, name_, long_name_)                    \
00498 AVCodec ff_ ## name_ ## _decoder = {                                        \
00499     .name           = #name_,                                               \
00500     .type           = AVMEDIA_TYPE_AUDIO,                                   \
00501     .id             = id_,                                                  \
00502     .priv_data_size = sizeof(PCMDecode),                                    \
00503     .init           = pcm_decode_init,                                      \
00504     .decode         = pcm_decode_frame,                                     \
00505     .capabilities   = CODEC_CAP_DR1,                                        \
00506     .sample_fmts    = (const enum AVSampleFormat[]){ sample_fmt_,           \
00507                                                      AV_SAMPLE_FMT_NONE },  \
00508     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),                     \
00509 }
00510 #else
00511 #define PCM_DECODER(id, sample_fmt_, name, long_name_)
00512 #endif
00513 
00514 #define PCM_CODEC(id, sample_fmt_, name, long_name_)                    \
00515     PCM_ENCODER(id, sample_fmt_, name, long_name_);                     \
00516     PCM_DECODER(id, sample_fmt_, name, long_name_)
00517 
00518 /* Note: Do not forget to add new entries to the Makefile as well. */
00519 PCM_CODEC  (CODEC_ID_PCM_ALAW,         AV_SAMPLE_FMT_S16, pcm_alaw,         "PCM A-law / G.711 A-law");
00520 PCM_DECODER(CODEC_ID_PCM_DVD,          AV_SAMPLE_FMT_S32, pcm_dvd,          "PCM signed 20|24-bit big-endian");
00521 PCM_CODEC  (CODEC_ID_PCM_F32BE,        AV_SAMPLE_FMT_FLT, pcm_f32be,        "PCM 32-bit floating point big-endian");
00522 PCM_CODEC  (CODEC_ID_PCM_F32LE,        AV_SAMPLE_FMT_FLT, pcm_f32le,        "PCM 32-bit floating point little-endian");
00523 PCM_CODEC  (CODEC_ID_PCM_F64BE,        AV_SAMPLE_FMT_DBL, pcm_f64be,        "PCM 64-bit floating point big-endian");
00524 PCM_CODEC  (CODEC_ID_PCM_F64LE,        AV_SAMPLE_FMT_DBL, pcm_f64le,        "PCM 64-bit floating point little-endian");
00525 PCM_DECODER(CODEC_ID_PCM_LXF,          AV_SAMPLE_FMT_S32P,pcm_lxf,          "PCM signed 20-bit little-endian planar");
00526 PCM_CODEC  (CODEC_ID_PCM_MULAW,        AV_SAMPLE_FMT_S16, pcm_mulaw,        "PCM mu-law / G.711 mu-law");
00527 PCM_CODEC  (CODEC_ID_PCM_S8,           AV_SAMPLE_FMT_U8,  pcm_s8,           "PCM signed 8-bit");
00528 PCM_CODEC  (CODEC_ID_PCM_S16BE,        AV_SAMPLE_FMT_S16, pcm_s16be,        "PCM signed 16-bit big-endian");
00529 PCM_CODEC  (CODEC_ID_PCM_S16LE,        AV_SAMPLE_FMT_S16, pcm_s16le,        "PCM signed 16-bit little-endian");
00530 PCM_DECODER(CODEC_ID_PCM_S16LE_PLANAR, AV_SAMPLE_FMT_S16P,pcm_s16le_planar, "PCM 16-bit little-endian planar");
00531 PCM_CODEC  (CODEC_ID_PCM_S24BE,        AV_SAMPLE_FMT_S32, pcm_s24be,        "PCM signed 24-bit big-endian");
00532 PCM_CODEC  (CODEC_ID_PCM_S24DAUD,      AV_SAMPLE_FMT_S16, pcm_s24daud,      "PCM D-Cinema audio signed 24-bit");
00533 PCM_CODEC  (CODEC_ID_PCM_S24LE,        AV_SAMPLE_FMT_S32, pcm_s24le,        "PCM signed 24-bit little-endian");
00534 PCM_CODEC  (CODEC_ID_PCM_S32BE,        AV_SAMPLE_FMT_S32, pcm_s32be,        "PCM signed 32-bit big-endian");
00535 PCM_CODEC  (CODEC_ID_PCM_S32LE,        AV_SAMPLE_FMT_S32, pcm_s32le,        "PCM signed 32-bit little-endian");
00536 PCM_CODEC  (CODEC_ID_PCM_U8,           AV_SAMPLE_FMT_U8,  pcm_u8,           "PCM unsigned 8-bit");
00537 PCM_CODEC  (CODEC_ID_PCM_U16BE,        AV_SAMPLE_FMT_S16, pcm_u16be,        "PCM unsigned 16-bit big-endian");
00538 PCM_CODEC  (CODEC_ID_PCM_U16LE,        AV_SAMPLE_FMT_S16, pcm_u16le,        "PCM unsigned 16-bit little-endian");
00539 PCM_CODEC  (CODEC_ID_PCM_U24BE,        AV_SAMPLE_FMT_S32, pcm_u24be,        "PCM unsigned 24-bit big-endian");
00540 PCM_CODEC  (CODEC_ID_PCM_U24LE,        AV_SAMPLE_FMT_S32, pcm_u24le,        "PCM unsigned 24-bit little-endian");
00541 PCM_CODEC  (CODEC_ID_PCM_U32BE,        AV_SAMPLE_FMT_S32, pcm_u32be,        "PCM unsigned 32-bit big-endian");
00542 PCM_CODEC  (CODEC_ID_PCM_U32LE,        AV_SAMPLE_FMT_S32, pcm_u32le,        "PCM unsigned 32-bit little-endian");
00543 PCM_DECODER(CODEC_ID_PCM_ZORK,         AV_SAMPLE_FMT_U8,  pcm_zork,         "PCM Zork");
00544