libavformat/wav.c

   1 /*
   2  * WAV muxer and demuxer
   3  * Copyright (c) 2001, 2002 Fabrice Bellard
   4  *
   5  * This file is part of FFmpeg.
   6  *
   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.
  11  *
  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.
  16  *
  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
  20  */
  21 #include "avformat.h"
  22 #include "raw.h"
  23 #include "riff.h"
  24
  25 typedef struct {
  26     int64_t data;
  27     int64_t data_end;
  28     int64_t minpts;
  29     int64_t maxpts;
  30     int last_duration;
  31 } WAVContext;
  32
  33 #if CONFIG_WAV_MUXER
  34 static int wav_write_header(AVFormatContext *s)
  35 {
  36     WAVContext *wav = s->priv_data;
  37     ByteIOContext *pb = s->pb;
  38     int64_t fmt, fact;
  39
  40     put_tag(pb, "RIFF");
  41     put_le32(pb, 0); /* file length */
  42     put_tag(pb, "WAVE");
  43
  44     /* format header */
  45     fmt = start_tag(pb, "fmt ");
  46     if (put_wav_header(pb, s->streams[0]->codec) < 0) {
  47         av_log(s, AV_LOG_ERROR, "%s codec not supported in WAVE format\n",
  48                s->streams[0]->codec->codec ? s->streams[0]->codec->codec->name : "NONE");
  49         av_free(wav);
  50         return -1;
  51     }
  52     end_tag(pb, fmt);
  53
  54     if(s->streams[0]->codec->codec_tag != 0x01 /* hence for all other than PCM */
  55        && !url_is_streamed(s->pb)) {
  56         fact = start_tag(pb, "fact");
  57         put_le32(pb, 0);
  58         end_tag(pb, fact);
  59     }
  60
  61     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
  62     wav->maxpts = wav->last_duration = 0;
  63     wav->minpts = INT64_MAX;
  64
  65     /* data header */
  66     wav->data = start_tag(pb, "data");
  67
  68     put_flush_packet(pb);
  69
  70     return 0;
  71 }
  72
  73 static int wav_write_packet(AVFormatContext *s, AVPacket *pkt)
  74 {
  75     ByteIOContext *pb = s->pb;
  76     WAVContext *wav = s->priv_data;
  77     put_buffer(pb, pkt->data, pkt->size);
  78     if(pkt->pts != AV_NOPTS_VALUE) {
  79         wav->minpts = FFMIN(wav->minpts, pkt->pts);
  80         wav->maxpts = FFMAX(wav->maxpts, pkt->pts);
  81         wav->last_duration = pkt->duration;
  82     } else
  83         av_log(s, AV_LOG_ERROR, "wav_write_packet: NOPTS\n");
  84     return 0;
  85 }
  86
  87 static int wav_write_trailer(AVFormatContext *s)
  88 {
  89     ByteIOContext *pb = s->pb;
  90     WAVContext *wav = s->priv_data;
  91     int64_t file_size;
  92
  93     if (!url_is_streamed(s->pb)) {
  94         end_tag(pb, wav->data);
  95
  96         /* update file size */
  97         file_size = url_ftell(pb);
  98         url_fseek(pb, 4, SEEK_SET);
  99         put_le32(pb, (uint32_t)(file_size - 8));
 100         url_fseek(pb, file_size, SEEK_SET);
 101
 102         put_flush_packet(pb);
 103
 104         if(s->streams[0]->codec->codec_tag != 0x01) {
 105             /* Update num_samps in fact chunk */
 106             int number_of_samples;
 107             number_of_samples = av_rescale(wav->maxpts - wav->minpts + wav->last_duration,
 108                                            s->streams[0]->codec->sample_rate * (int64_t)s->streams[0]->time_base.num,
 109                                            s->streams[0]->time_base.den);
 110             url_fseek(pb, wav->data-12, SEEK_SET);
 111             put_le32(pb, number_of_samples);
 112             url_fseek(pb, file_size, SEEK_SET);
 113             put_flush_packet(pb);
 114         }
 115     }
 116     return 0;
 117 }
 118 #endif /* CONFIG_WAV_MUXER */
 119
 120 /* return the size of the found tag */
 121 static int64_t find_tag(ByteIOContext *pb, uint32_t tag1)
 122 {
 123     unsigned int tag;
 124     int64_t size;
 125
 126     for(;;) {
 127         if (url_feof(pb))
 128             return -1;
 129         tag = get_le32(pb);
 130         size = get_le32(pb);
 131         if (tag == tag1)
 132             break;
 133         url_fseek(pb, size, SEEK_CUR);
 134     }
 135     return size;
 136 }
 137
 138 static int wav_probe(AVProbeData *p)
 139 {
 140     /* check file header */
 141     if (p->buf_size <= 32)
 142         return 0;
 143     if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
 144         p->buf[2] == 'F' && p->buf[3] == 'F' &&
 145         p->buf[8] == 'W' && p->buf[9] == 'A' &&
 146         p->buf[10] == 'V' && p->buf[11] == 'E')
 147         /*
 148           Since ACT demuxer has standard WAV header at top of it's own,
 149           returning score is decreased to avoid probe conflict
 150           between ACT and WAV.
 151         */
 152         return AVPROBE_SCORE_MAX - 1;
 153     else
 154         return 0;
 155 }
 156
 157 /* wav input */
 158 static int wav_read_header(AVFormatContext *s,
 159                            AVFormatParameters *ap)
 160 {
 161     int64_t size;
 162     unsigned int tag;
 163     ByteIOContext *pb = s->pb;
 164     AVStream *st;
 165     WAVContext *wav = s->priv_data;
 166
 167     /* check RIFF header */
 168     tag = get_le32(pb);
 169
 170     if (tag != MKTAG('R', 'I', 'F', 'F'))
 171         return -1;
 172     get_le32(pb); /* file size */
 173     tag = get_le32(pb);
 174     if (tag != MKTAG('W', 'A', 'V', 'E'))
 175         return -1;
 176
 177     /* parse fmt header */
 178     size = find_tag(pb, MKTAG('f', 'm', 't', ' '));
 179     if (size < 0)
 180         return -1;
 181     st = av_new_stream(s, 0);
 182     if (!st)
 183         return AVERROR(ENOMEM);
 184
 185     get_wav_header(pb, st->codec, size);
 186     st->need_parsing = AVSTREAM_PARSE_FULL;
 187
 188     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
 189
 190     size = find_tag(pb, MKTAG('d', 'a', 't', 'a'));
 191     if (size < 0)
 192         return -1;
 193     wav->data_end= url_ftell(pb) + size;
 194     return 0;
 195 }
 196
 197 #define MAX_SIZE 4096
 198
 199 static int wav_read_packet(AVFormatContext *s,
 200                            AVPacket *pkt)
 201 {
 202     int ret, size, left;
 203     AVStream *st;
 204     WAVContext *wav = s->priv_data;
 205
 206     if (url_feof(s->pb))
 207         return AVERROR(EIO);
 208     st = s->streams[0];
 209
 210     left= wav->data_end - url_ftell(s->pb);
 211     if(left <= 0){
 212         left = find_tag(s->pb, MKTAG('d', 'a', 't', 'a'));
 213         if (left < 0) {
 214             return AVERROR(EIO);
 215         }
 216         wav->data_end= url_ftell(s->pb) + left;
 217     }
 218
 219     size = MAX_SIZE;
 220     if (st->codec->block_align > 1) {
 221         if (size < st->codec->block_align)
 222             size = st->codec->block_align;
 223         size = (size / st->codec->block_align) * st->codec->block_align;
 224     }
 225     size= FFMIN(size, left);
 226     ret= av_get_packet(s->pb, pkt, size);
 227     if (ret <= 0)
 228         return AVERROR(EIO);
 229     pkt->stream_index = 0;
 230
 231     /* note: we need to modify the packet size here to handle the last
 232        packet */
 233     pkt->size = ret;
 234     return ret;
 235 }
 236
 237 static int wav_read_seek(AVFormatContext *s,
 238                          int stream_index, int64_t timestamp, int flags)
 239 {
 240     AVStream *st;
 241
 242     st = s->streams[0];
 243     switch(st->codec->codec_id) {
 244     case CODEC_ID_MP2:
 245     case CODEC_ID_MP3:
 246     case CODEC_ID_AC3:
 247     case CODEC_ID_DTS:
 248         /* use generic seeking with dynamically generated indexes */
 249         return -1;
 250     default:
 251         break;
 252     }
 253     return pcm_read_seek(s, stream_index, timestamp, flags);
 254 }
 255
 256 #if CONFIG_WAV_DEMUXER
 257 AVInputFormat wav_demuxer = {
 258     "wav",
 259     NULL_IF_CONFIG_SMALL("WAV format"),
 260     sizeof(WAVContext),
 261     wav_probe,
 262     wav_read_header,
 263     wav_read_packet,
 264     NULL,
 265     wav_read_seek,
 266     .flags= AVFMT_GENERIC_INDEX,
 267     .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
 268 };
 269 #endif
 270 #if CONFIG_WAV_MUXER
 271 AVOutputFormat wav_muxer = {
 272     "wav",
 273     NULL_IF_CONFIG_SMALL("WAV format"),
 274     "audio/x-wav",
 275     "wav",
 276     sizeof(WAVContext),
 277     CODEC_ID_PCM_S16LE,
 278     CODEC_ID_NONE,
 279     wav_write_header,
 280     wav_write_packet,
 281     wav_write_trailer,
 282     .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
 283 };
 284 #endif