libavformat/wv.c

   1 /*
   2  * WavPack demuxer
   3  * Copyright (c) 2006 Konstantin Shishkov
   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
  22 #include "libavutil/intreadwrite.h"
  23 #include "avformat.h"
  24
  25 // specs say that maximum block size is 1Mb
  26 #define WV_BLOCK_LIMIT 1047576
  27
  28 #define WV_EXTRA_SIZE 12
  29
  30 enum WV_FLAGS{
  31     WV_MONO   = 0x0004,
  32     WV_HYBRID = 0x0008,
  33     WV_JOINT  = 0x0010,
  34     WV_CROSSD = 0x0020,
  35     WV_HSHAPE = 0x0040,
  36     WV_FLOAT  = 0x0080,
  37     WV_INT32  = 0x0100,
  38     WV_HBR    = 0x0200,
  39     WV_HBAL   = 0x0400,
  40     WV_MCINIT = 0x0800,
  41     WV_MCEND  = 0x1000,
  42 };
  43
  44 static const int wv_rates[16] = {
  45      6000,  8000,  9600, 11025, 12000, 16000, 22050, 24000,
  46     32000, 44100, 48000, 64000, 88200, 96000, 192000, -1
  47 };
  48
  49 typedef struct{
  50     uint32_t blksize, flags;
  51     int rate, chan, bpp;
  52     uint32_t samples, soff;
  53     int block_parsed;
  54     uint8_t extra[WV_EXTRA_SIZE];
  55     int64_t pos;
  56 }WVContext;
  57
  58 static int wv_probe(AVProbeData *p)
  59 {
  60     /* check file header */
  61     if (p->buf_size <= 32)
  62         return 0;
  63     if (p->buf[0] == 'w' && p->buf[1] == 'v' &&
  64         p->buf[2] == 'p' && p->buf[3] == 'k')
  65         return AVPROBE_SCORE_MAX;
  66     else
  67         return 0;
  68 }
  69
  70 static int wv_read_block_header(AVFormatContext *ctx, ByteIOContext *pb)
  71 {
  72     WVContext *wc = ctx->priv_data;
  73     uint32_t tag, ver;
  74     int size;
  75     int rate, bpp, chan;
  76
  77     wc->pos = url_ftell(pb);
  78     tag = get_le32(pb);
  79     if (tag != MKTAG('w', 'v', 'p', 'k'))
  80         return -1;
  81     size = get_le32(pb);
  82     if(size < 24 || size > WV_BLOCK_LIMIT){
  83         av_log(ctx, AV_LOG_ERROR, "Incorrect block size %i\n", size);
  84         return -1;
  85     }
  86     wc->blksize = size;
  87     ver = get_le16(pb);
  88     if(ver < 0x402 || ver > 0x410){
  89         av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", ver);
  90         return -1;
  91     }
  92     get_byte(pb); // track no
  93     get_byte(pb); // track sub index
  94     wc->samples = get_le32(pb); // total samples in file
  95     wc->soff = get_le32(pb); // offset in samples of current block
  96     get_buffer(pb, wc->extra, WV_EXTRA_SIZE);
  97     wc->flags = AV_RL32(wc->extra + 4);
  98     //parse flags
  99     bpp = ((wc->flags & 3) + 1) << 3;
 100     chan = 1 + !(wc->flags & WV_MONO);
 101     rate = wv_rates[(wc->flags >> 23) & 0xF];
 102     if(rate == -1){
 103         av_log(ctx, AV_LOG_ERROR, "Unknown sampling rate\n");
 104         return -1;
 105     }
 106     if(!wc->bpp) wc->bpp = bpp;
 107     if(!wc->chan) wc->chan = chan;
 108     if(!wc->rate) wc->rate = rate;
 109
 110     if(wc->flags && bpp != wc->bpp){
 111         av_log(ctx, AV_LOG_ERROR, "Bits per sample differ, this block: %i, header block: %i\n", bpp, wc->bpp);
 112         return -1;
 113     }
 114     if(wc->flags && chan != wc->chan){
 115         av_log(ctx, AV_LOG_ERROR, "Channels differ, this block: %i, header block: %i\n", chan, wc->chan);
 116         return -1;
 117     }
 118     if(wc->flags && rate != wc->rate){
 119         av_log(ctx, AV_LOG_ERROR, "Sampling rate differ, this block: %i, header block: %i\n", rate, wc->rate);
 120         return -1;
 121     }
 122     wc->blksize = size - 24;
 123     return 0;
 124 }
 125
 126 static int wv_read_header(AVFormatContext *s,
 127                           AVFormatParameters *ap)
 128 {
 129     ByteIOContext *pb = s->pb;
 130     WVContext *wc = s->priv_data;
 131     AVStream *st;
 132
 133     if(wv_read_block_header(s, pb) < 0)
 134         return -1;
 135
 136     wc->block_parsed = 0;
 137     /* now we are ready: build format streams */
 138     st = av_new_stream(s, 0);
 139     if (!st)
 140         return -1;
 141     st->codec->codec_type = CODEC_TYPE_AUDIO;
 142     st->codec->codec_id = CODEC_ID_WAVPACK;
 143     st->codec->channels = wc->chan;
 144     st->codec->sample_rate = wc->rate;
 145     st->codec->bits_per_coded_sample = wc->bpp;
 146     av_set_pts_info(st, 64, 1, wc->rate);
 147     s->start_time = 0;
 148     s->duration = (int64_t)wc->samples * AV_TIME_BASE / st->codec->sample_rate;
 149     return 0;
 150 }
 151
 152 static int wv_read_packet(AVFormatContext *s,
 153                           AVPacket *pkt)
 154 {
 155     WVContext *wc = s->priv_data;
 156     int ret;
 157
 158     if (url_feof(s->pb))
 159         return AVERROR(EIO);
 160     if(wc->block_parsed){
 161         if(wv_read_block_header(s, s->pb) < 0)
 162             return -1;
 163     }
 164
 165     if(av_new_packet(pkt, wc->blksize + WV_EXTRA_SIZE) < 0)
 166         return AVERROR(ENOMEM);
 167     memcpy(pkt->data, wc->extra, WV_EXTRA_SIZE);
 168     ret = get_buffer(s->pb, pkt->data + WV_EXTRA_SIZE, wc->blksize);
 169     if(ret != wc->blksize){
 170         av_free_packet(pkt);
 171         return AVERROR(EIO);
 172     }
 173     pkt->stream_index = 0;
 174     wc->block_parsed = 1;
 175     pkt->size = ret + WV_EXTRA_SIZE;
 176     pkt->pts = wc->soff;
 177     av_add_index_entry(s->streams[0], wc->pos, pkt->pts, 0, 0, AVINDEX_KEYFRAME);
 178     return 0;
 179 }
 180
 181 static int wv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
 182 {
 183     AVStream *st = s->streams[stream_index];
 184     WVContext *wc = s->priv_data;
 185     AVPacket pkt1, *pkt = &pkt1;
 186     int ret;
 187     int index = av_index_search_timestamp(st, timestamp, flags);
 188     int64_t pos, pts;
 189
 190     /* if found, seek there */
 191     if (index >= 0){
 192         wc->block_parsed = 1;
 193         url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET);
 194         return 0;
 195     }
 196     /* if timestamp is out of bounds, return error */
 197     if(timestamp < 0 || timestamp >= s->duration)
 198         return -1;
 199
 200     pos = url_ftell(s->pb);
 201     do{
 202         ret = av_read_frame(s, pkt);
 203         if (ret < 0){
 204             url_fseek(s->pb, pos, SEEK_SET);
 205             return -1;
 206         }
 207         pts = pkt->pts;
 208         av_free_packet(pkt);
 209     }while(pts < timestamp);
 210     return 0;
 211 }
 212
 213 AVInputFormat wv_demuxer = {
 214     "wv",
 215     NULL_IF_CONFIG_SMALL("WavPack"),
 216     sizeof(WVContext),
 217     wv_probe,
 218     wv_read_header,
 219     wv_read_packet,
 220     NULL,
 221     wv_read_seek,
 222 };