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     offset_t data;
  27     offset_t data_end;
  28     int64_t minpts;
  29     int64_t maxpts;
  30     int last_duration;
  31 } WAVContext;
  32
  33 #ifdef CONFIG_MUXERS
  34 static int wav_write_header(AVFormatContext *s)
  35 {
  36     WAVContext *wav = s->priv_data;
  37     ByteIOContext *pb = s->pb;
  38     offset_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_free(wav);
  48         return -1;
  49     }
  50     end_tag(pb, fmt);
  51
  52     if(s->streams[0]->codec->codec_tag != 0x01 /* hence for all other than PCM */
  53        && !url_is_streamed(s->pb)) {
  54         fact = start_tag(pb, "fact");
  55         put_le32(pb, 0);
  56         end_tag(pb, fact);
  57     }
  58
  59     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
  60     wav->maxpts = wav->last_duration = 0;
  61     wav->minpts = INT64_MAX;
  62
  63     /* data header */
  64     wav->data = start_tag(pb, "data");
  65
  66     put_flush_packet(pb);
  67
  68     return 0;
  69 }
  70
  71 static int wav_write_packet(AVFormatContext *s, AVPacket *pkt)
  72 {
  73     ByteIOContext *pb = s->pb;
  74     WAVContext *wav = s->priv_data;
  75     put_buffer(pb, pkt->data, pkt->size);
  76     if(pkt->pts != AV_NOPTS_VALUE) {
  77         wav->minpts = FFMIN(wav->minpts, pkt->pts);
  78         wav->maxpts = FFMAX(wav->maxpts, pkt->pts);
  79         wav->last_duration = pkt->duration;
  80     } else
  81         av_log(s, AV_LOG_ERROR, "wav_write_packet: NOPTS\n");
  82     return 0;
  83 }
  84
  85 static int wav_write_trailer(AVFormatContext *s)
  86 {
  87     ByteIOContext *pb = s->pb;
  88     WAVContext *wav = s->priv_data;
  89     offset_t file_size;
  90
  91     if (!url_is_streamed(s->pb)) {
  92         end_tag(pb, wav->data);
  93
  94         /* update file size */
  95         file_size = url_ftell(pb);
  96         url_fseek(pb, 4, SEEK_SET);
  97         put_le32(pb, (uint32_t)(file_size - 8));
  98         url_fseek(pb, file_size, SEEK_SET);
  99
 100         put_flush_packet(pb);
 101
 102         if(s->streams[0]->codec->codec_tag != 0x01) {
 103             /* Update num_samps in fact chunk */
 104             int number_of_samples;
 105             number_of_samples = av_rescale(wav->maxpts - wav->minpts + wav->last_duration,
 106                                            s->streams[0]->codec->sample_rate * (int64_t)s->streams[0]->time_base.num,
 107                                            s->streams[0]->time_base.den);
 108             url_fseek(pb, wav->data-12, SEEK_SET);
 109             put_le32(pb, number_of_samples);
 110             url_fseek(pb, file_size, SEEK_SET);
 111             put_flush_packet(pb);
 112         }
 113     }
 114     return 0;
 115 }
 116 #endif //CONFIG_MUXERS
 117
 118 /* return the size of the found tag */
 119 /* XXX: > 2GB ? */
 120 static int find_tag(ByteIOContext *pb, uint32_t tag1)
 121 {
 122     unsigned int tag;
 123     int size;
 124
 125     for(;;) {
 126         if (url_feof(pb))
 127             return -1;
 128         tag = get_le32(pb);
 129         size = get_le32(pb);
 130         if (tag == tag1)
 131             break;
 132         url_fseek(pb, size, SEEK_CUR);
 133     }
 134     if (size < 0)
 135         size = 0x7fffffff;
 136     return size;
 137 }
 138
 139 static int wav_probe(AVProbeData *p)
 140 {
 141     /* check file header */
 142     if (p->buf_size <= 32)
 143         return 0;
 144     if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
 145         p->buf[2] == 'F' && p->buf[3] == 'F' &&
 146         p->buf[8] == 'W' && p->buf[9] == 'A' &&
 147         p->buf[10] == 'V' && p->buf[11] == 'E')
 148         /*
 149           Since ACT demuxer has standard WAV header at top of it's own,
 150           returning score is decreased to avoid probe conflict
 151           between ACT and WAV.
 152         */
 153         return AVPROBE_SCORE_MAX - 1;
 154     else
 155         return 0;
 156 }
 157
 158 /* wav input */
 159 static int wav_read_header(AVFormatContext *s,
 160                            AVFormatParameters *ap)
 161 {
 162     int size;
 163     unsigned int tag;
 164     ByteIOContext *pb = s->pb;
 165     AVStream *st;
 166     WAVContext *wav = s->priv_data;
 167
 168     /* check RIFF header */
 169     tag = get_le32(pb);
 170
 171     if (tag != MKTAG('R', 'I', 'F', 'F'))
 172         return -1;
 173     get_le32(pb); /* file size */
 174     tag = get_le32(pb);
 175     if (tag != MKTAG('W', 'A', 'V', 'E'))
 176         return -1;
 177
 178     /* parse fmt header */
 179     size = find_tag(pb, MKTAG('f', 'm', 't', ' '));
 180     if (size < 0)
 181         return -1;
 182     st = av_new_stream(s, 0);
 183     if (!st)
 184         return AVERROR(ENOMEM);
 185
 186     get_wav_header(pb, st->codec, size);
 187     st->need_parsing = AVSTREAM_PARSE_FULL;
 188
 189     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
 190
 191     size = find_tag(pb, MKTAG('d', 'a', 't', 'a'));
 192     if (size < 0)
 193         return -1;
 194     wav->data_end= url_ftell(pb) + size;
 195     return 0;
 196 }
 197
 198 #define MAX_SIZE 4096
 199
 200 static int wav_read_packet(AVFormatContext *s,
 201                            AVPacket *pkt)
 202 {
 203     int ret, size, left;
 204     AVStream *st;
 205     WAVContext *wav = s->priv_data;
 206
 207     if (url_feof(s->pb))
 208         return AVERROR(EIO);
 209     st = s->streams[0];
 210
 211     left= wav->data_end - url_ftell(s->pb);
 212     if(left <= 0){
 213         left = find_tag(s->pb, MKTAG('d', 'a', 't', 'a'));
 214         if (left < 0) {
 215             return AVERROR(EIO);
 216         }
 217         wav->data_end= url_ftell(s->pb) + left;
 218     }
 219
 220     size = MAX_SIZE;
 221     if (st->codec->block_align > 1) {
 222         if (size < st->codec->block_align)
 223             size = st->codec->block_align;
 224         size = (size / st->codec->block_align) * st->codec->block_align;
 225     }
 226     size= FFMIN(size, left);
 227     ret= av_get_packet(s->pb, pkt, size);
 228     if (ret <= 0)
 229         return AVERROR(EIO);
 230     pkt->stream_index = 0;
 231
 232     /* note: we need to modify the packet size here to handle the last
 233        packet */
 234     pkt->size = ret;
 235     return ret;
 236 }
 237
 238 static int wav_read_seek(AVFormatContext *s,
 239                          int stream_index, int64_t timestamp, int flags)
 240 {
 241     AVStream *st;
 242
 243     st = s->streams[0];
 244     switch(st->codec->codec_id) {
 245     case CODEC_ID_MP2:
 246     case CODEC_ID_MP3:
 247     case CODEC_ID_AC3:
 248     case CODEC_ID_DTS:
 249         /* use generic seeking with dynamically generated indexes */
 250         return -1;
 251     default:
 252         break;
 253     }
 254     return pcm_read_seek(s, stream_index, timestamp, flags);
 255 }
 256
 257 #ifdef CONFIG_WAV_DEMUXER
 258 AVInputFormat wav_demuxer = {
 259     "wav",
 260     NULL_IF_CONFIG_SMALL("WAV format"),
 261     sizeof(WAVContext),
 262     wav_probe,
 263     wav_read_header,
 264     wav_read_packet,
 265     NULL,
 266     wav_read_seek,
 267     .flags= AVFMT_GENERIC_INDEX,
 268     .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
 269 };
 270 #endif
 271 #ifdef CONFIG_WAV_MUXER
 272 AVOutputFormat wav_muxer = {
 273     "wav",
 274     NULL_IF_CONFIG_SMALL("WAV format"),
 275     "audio/x-wav",
 276     "wav",
 277     sizeof(WAVContext),
 278     CODEC_ID_PCM_S16LE,
 279     CODEC_ID_NONE,
 280     wav_write_header,
 281     wav_write_packet,
 282     wav_write_trailer,
 283     .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
 284 };
 285 #endif